:root{--primary:#0d6efd;--primary-dark:#0b5ed7;--primary-light:#eaf3ff;--bg-soft:#f5f9ff;--border:#d6e4f5;--text-main:#1f2937;--text-muted:#6b7280;--success:#198754;--danger:#dc3545;--warning:#b7791f}*{box-sizing:border-box}body{margin:0;font-family:Arial,"Segoe UI",sans-serif;color:var(--text-main);background:var(--bg-soft)}a{color:var(--primary);text-decoration:none}.login-page{min-height:100vh;background:linear-gradient(135deg,#eaf3ff,#fff);display:flex;align-items:center;justify-content:center}.login-container{width:100%;max-width:430px;padding:20px}.login-card{background:#fff;border:1px solid var(--border);border-radius:16px;box-shadow:0 10px 30px rgba(13,110,253,.12);padding:32px}.login-card h1{text-align:center;color:var(--primary);margin:0}.subtitle{text-align:center;color:var(--text-muted)}label{display:block;margin-top:14px;margin-bottom:6px;font-weight:700}input,select,textarea{width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:8px;font-size:15px;background:#fff}textarea{min-height:220px;font-family:Consolas,monospace}button{border:0;cursor:pointer;font-family:inherit}.login-card button{width:100%;margin-top:20px;padding:12px;border-radius:8px;background:var(--primary);color:#fff;font-weight:700}.error-box,.flash-error{background:#fff1f1;color:var(--danger);border:1px solid #ffd0d0}.login-card .error-box{text-align:center;padding:12px 14px;border-radius:10px;line-height:1.45;font-weight:700;margin:16px 0 8px}.test-account,.hint-box{margin-top:18px;padding:12px;background:var(--primary-light);border:1px solid var(--border);border-radius:9px;line-height:1.5}.app-layout{min-height:100vh;display:flex}.sidebar{width:260px;background:#fff;border-right:1px solid var(--border);padding:18px 14px;position:fixed;top:0;bottom:0;left:0}.sidebar-logo{display:flex;gap:12px;align-items:center;padding:8px 8px 20px;border-bottom:1px solid var(--border)}.logo-icon{width:44px;height:44px;background:var(--primary);color:#fff;border-radius:12px;display:flex;align-items:center;justify-content:center;font-weight:800}.logo-title{font-size:18px;font-weight:800;color:var(--primary)}.logo-subtitle{font-size:13px;color:var(--text-muted)}.sidebar-menu{margin-top:18px}.menu-item{display:block;padding:11px 12px;margin-bottom:6px;border-radius:9px;color:var(--text-main);font-weight:700}.menu-item:hover{background:var(--primary-light);color:var(--primary)}.menu-item.active{background:var(--primary);color:#fff}.main-area{margin-left:260px;flex:1}.topbar{min-height:88px;background:#fff;border-bottom:1px solid var(--border);padding:16px 28px;display:flex;align-items:center;justify-content:space-between;gap:12px}.topbar h2{margin:0;font-size:24px}.topbar p{margin:5px 0 0;color:var(--text-muted)}.user-box{display:flex;align-items:center;gap:12px;background:var(--primary-light);border-radius:12px;padding:8px 10px}.user-name{font-weight:800}.user-role{font-size:13px;color:var(--text-muted)}.logout-btn{background:#fff;border:1px solid var(--border);padding:7px 10px;border-radius:8px;font-weight:700}.content{padding:26px 28px}.flash-area{margin-bottom:18px}.flash-message{padding:11px 14px;border-radius:9px;margin-bottom:8px;font-weight:700}.flash-success{background:#e8f7ee;color:var(--success);border:1px solid #bce3c8}.card{background:#fff;border:1px solid var(--border);border-radius:14px;padding:18px;margin-bottom:22px;box-shadow:0 4px 14px rgba(13,110,253,.06)}.card-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;gap:12px}.card-header h3{margin:0}.badge,.status,.tag{display:inline-block;padding:5px 9px;border-radius:999px;font-size:13px;font-weight:800;white-space:nowrap}.badge-success,.status-open{background:#e8f7ee;color:var(--success)}.badge-warning,.status-lock{background:#fff3cd;color:var(--warning)}.status-danger{background:#fff1f1;color:var(--danger)}.data-table,.info-table{width:100%;border-collapse:collapse}.data-table th,.data-table td,.info-table td{border-bottom:1px solid var(--border);padding:12px 10px;text-align:left;vertical-align:middle}.data-table th{background:var(--primary-light);color:var(--primary-dark)}.empty-cell{text-align:center;color:var(--text-muted);padding:24px!important}.small-btn,.small-link-btn,.form-submit-btn{display:inline-block;background:var(--primary);color:#fff;padding:9px 13px;border-radius:8px;font-weight:800;text-decoration:none;font-size:14px;margin-top:8px}.small-btn:hover,.small-link-btn:hover,.form-submit-btn:hover{background:var(--primary-dark);color:#fff}.danger-btn{background:var(--danger)}.secondary-btn{background:#64748b}.action-row,.table-actions,.import-form{display:flex;flex-wrap:wrap;gap:10px;align-items:center}.grid-2,.grid-3,.grid-4{display:grid;gap:16px;margin-bottom:22px}.grid-2{grid-template-columns:repeat(2,1fr)}.grid-3{grid-template-columns:repeat(3,1fr)}.grid-4{grid-template-columns:repeat(4,1fr)}.stat-card{background:#fff;border:1px solid var(--border);border-radius:14px;padding:20px;box-shadow:0 4px 14px rgba(13,110,253,.06)}.stat-number{font-size:30px;color:var(--primary);font-weight:900}.stat-label{margin-top:6px;color:var(--text-muted);font-weight:700}.form-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px 18px}.nice-list{line-height:1.7}.problem-layout{display:grid;grid-template-columns:1.1fr .9fr;gap:18px}.pdf-frame{width:100%;height:720px;border:1px solid var(--border);border-radius:10px;background:#fff}.code-page{background:#f8fafc;padding:22px}.code-card{background:#fff;border:1px solid var(--border);border-radius:12px;padding:18px}.code-view{background:#0f172a;color:#e5e7eb;padding:16px;border-radius:10px;overflow:auto;line-height:1.45;font-family:Consolas,monospace}hr{border:0;border-top:1px solid var(--border);margin:16px 0}@media(max-width:1000px){.sidebar{position:static;width:100%;height:auto}.app-layout{flex-direction:column}.main-area{margin-left:0}.topbar{height:auto;flex-direction:column;align-items:flex-start}.grid-2,.grid-3,.grid-4,.form-grid,.problem-layout{grid-template-columns:1fr}.table-actions{flex-direction:column;align-items:flex-start}.pdf-frame{height:480px}}


/* =========================
   V1.2 - đề bài lớn hơn, đổi mật khẩu, code sáng
   ========================= */

:root{--sidebar-width:245px}
body{font-size:16px}.sidebar{width:var(--sidebar-width)!important}.main-area{margin-left:var(--sidebar-width)!important}.content{padding:22px 24px!important}.topbar{min-height:76px!important;padding:12px 20px!important}.topbar h2{font-size:25px}.menu-item{font-size:15.5px;padding:12px 13px}.logo-title{font-size:18px}.logo-subtitle{font-size:13px}.user-box{gap:8px}.change-password-btn{background:#fff;border:1px solid var(--border);padding:7px 10px;border-radius:8px;font-weight:800;color:var(--primary);white-space:nowrap}.change-password-btn:hover{background:var(--primary);color:#fff}.password-page{max-width:650px}.password-card{padding:24px}.password-form{max-width:530px}.problem-layout-large{display:grid!important;grid-template-columns:minmax(900px,2.35fr) minmax(340px,.65fr)!important;gap:18px!important;align-items:start!important}.problem-statement{padding:16px!important}.pdf-frame,.pdf-frame-large{width:100%!important;height:calc(100vh - 150px)!important;min-height:850px!important;border:1px solid var(--border);border-radius:10px;background:#fff}.submit-side{min-width:0}.submit-card textarea{min-height:170px!important}.secondary-open-btn{background:#64748b!important;margin-top:0!important}.no-margin-btn{margin-top:0!important;padding:7px 10px!important}.table-actions form,.data-table form{margin:0}.code-page.light-code-page{background:#eef5ff;padding:26px}.light-code-card{max-width:1200px;margin:0 auto;background:#fff;border:1px solid var(--border);border-radius:16px;padding:22px;box-shadow:0 8px 24px rgba(13,110,253,.10)}.code-header{display:flex;justify-content:space-between;align-items:flex-start;gap:16px;margin-bottom:12px}.code-header h2{margin:0 0 6px;color:var(--primary)}.code-header p{margin:0;color:var(--text-muted)}.code-view-light{background:#f8fbff!important;color:#1f2937!important;border:1px solid #d6e4f5;border-left:6px solid var(--primary);font-size:15px;line-height:1.55;padding:18px!important;border-radius:12px;white-space:pre;tab-size:4;box-shadow:inset 0 0 0 1px rgba(13,110,253,.04)}@media(max-width:1500px){.problem-layout-large{grid-template-columns:minmax(760px,2fr) minmax(330px,.8fr)!important}.pdf-frame,.pdf-frame-large{min-height:760px!important}}@media(max-width:1150px){.problem-layout-large{grid-template-columns:1fr!important}.pdf-frame,.pdf-frame-large{height:78vh!important;min-height:650px!important}}@media(max-width:1000px){.sidebar{width:100%!important}.main-area{margin-left:0!important}.content{padding:18px!important}.code-header{flex-direction:column}.pdf-frame,.pdf-frame-large{height:72vh!important;min-height:560px!important}}


/* =========================
   V1.3 - menu tài khoản dạng xổ xuống + login lớn hơn
   ========================= */

/* Bỏ nút đổi mật khẩu dạng cũ nếu trình duyệt còn cache cấu trúc cũ */
.user-box .change-password-btn {
    display: none !important;
}

/* Topbar gọn và hiện đại hơn */
.topbar {
    overflow: visible !important;
    position: relative;
    z-index: 20;
}

.topbar-title {
    min-width: 0;
}

.user-menu {
    position: relative;
    flex-shrink: 0;
}

.user-menu summary {
    list-style: none;
}

.user-menu summary::-webkit-details-marker {
    display: none;
}

.user-summary {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--primary-light);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 8px 10px;
    cursor: pointer;
    user-select: none;
    min-width: 210px;
}

.user-summary:hover {
    background: #dfeeff;
}

.user-avatar {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    font-size: 18px;
}

.user-summary-text {
    flex: 1;
    min-width: 0;
}

.user-summary .user-name {
    max-width: 170px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.user-caret {
    color: var(--primary);
    font-weight: 900;
}

.user-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 210px;
    background: #ffffff;
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: 0 12px 32px rgba(15, 23, 42, 0.14);
    padding: 8px;
    z-index: 100;
}

.user-dropdown a {
    display: block;
    padding: 11px 12px;
    border-radius: 9px;
    color: var(--text-main);
    font-weight: 800;
}

.user-dropdown a:hover {
    background: var(--primary-light);
    color: var(--primary);
}

/* Login lớn và dễ nhìn hơn */
.login-container,
.login-container-large {
    max-width: 540px !important;
}

.login-card,
.login-card-large {
    padding: 44px 42px !important;
    border-radius: 22px !important;
    box-shadow: 0 18px 46px rgba(13, 110, 253, 0.16) !important;
}

.login-logo-big {
    width: 62px;
    height: 62px;
    border-radius: 18px;
    margin: 0 auto 18px;
    background: var(--primary);
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 900;
    box-shadow: 0 10px 22px rgba(13, 110, 253, 0.24);
}

.login-card h1 {
    font-size: 32px !important;
    line-height: 1.18;
}

.login-card .subtitle {
    font-size: 16px;
    margin: 12px 0 30px;
}

.login-card label {
    font-size: 16px;
}

.login-card input {
    min-height: 48px;
    padding: 13px 14px;
    font-size: 16px !important;
}

.login-card button {
    min-height: 50px;
    font-size: 17px;
    border-radius: 10px;
}

.login-card .test-account {
    font-size: 15px;
    padding: 14px;
}

/* Đề bài vẫn ưu tiên hiển thị rất lớn */
.problem-layout-large {
    grid-template-columns: minmax(980px, 2.6fr) minmax(320px, .6fr) !important;
}

.pdf-frame,
.pdf-frame-large {
    height: calc(100vh - 135px) !important;
    min-height: 900px !important;
}

/* Nền xem code sáng, rõ dòng hơn */
.code-view-light {
    background: #fbfdff !important;
    color: #111827 !important;
    border-left: 7px solid var(--primary) !important;
    font-size: 15.5px !important;
    line-height: 1.6 !important;
}

@media(max-width:1150px) {
    .user-summary {
        min-width: 180px;
    }

    .problem-layout-large {
        grid-template-columns: 1fr !important;
    }

    .pdf-frame,
    .pdf-frame-large {
        min-height: 680px !important;
        height: 76vh !important;
    }
}

@media(max-width:700px) {
    .login-container,
    .login-container-large {
        max-width: 96% !important;
    }

    .login-card,
    .login-card-large {
        padding: 32px 24px !important;
    }

    .login-card h1 {
        font-size: 27px !important;
    }

    .user-summary {
        min-width: 0;
        width: 100%;
    }

    .user-dropdown {
        left: 0;
        right: auto;
        width: 100%;
    }
}


/* =========================
   V1.4 - nâng cấp trải nghiệm dùng thật
   ========================= */

.problem-toolbar {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 14px;
    flex-wrap: wrap;
}


.problem-layout-large {
    grid-template-columns: minmax(1050px, 3fr) minmax(330px, .55fr) !important;
    gap: 18px !important;
}

.pdf-frame,
.pdf-frame-large {
    height: calc(100vh - 112px) !important;
    min-height: 960px !important;
    background: #ffffff;
}

.statement-focus-mode .sidebar,
.statement-focus-mode .topbar,
.statement-focus-mode .problem-toolbar,
.statement-focus-mode .submit-side {
    display: none !important;
}

.statement-focus-mode .main-area {
    margin-left: 0 !important;
}

.statement-focus-mode .content {
    padding: 0 !important;
}

.statement-focus-layout {
    display: block !important;
}

.statement-focus-layout .problem-statement {
    border-radius: 0 !important;
    min-height: 100vh;
    margin: 0 !important;
    border: none !important;
}

.statement-focus-layout .pdf-frame,
.statement-focus-layout .pdf-frame-large {
    height: calc(100vh - 72px) !important;
    min-height: calc(100vh - 72px) !important;
}

.warning-btn {
    background: #f59e0b !important;
    color: #ffffff !important;
}

.warning-btn:hover {
    background: #d97706 !important;
}

.filter-form .form-submit-btn {
    margin-top: 0;
}

.tests-card {
    margin-bottom: 16px;
}

.danger-zone-card {
    border-color: #fecaca !important;
}

.danger-zone-card .card-header h3 {
    color: #b91c1c;
}

.code-view-light {
    background: #f8fafc !important;
    color: #111827 !important;
    border: 1px solid #dbeafe !important;
    border-left: 8px solid var(--primary) !important;
    border-radius: 14px !important;
    box-shadow: inset 0 0 0 1px #ffffff;
}

@media (max-width: 1300px) {
    .problem-layout-large {
        grid-template-columns: 1fr !important;
    }

    .pdf-frame,
    .pdf-frame-large {
        min-height: 780px !important;
        height: 78vh !important;
    }
}


/* =========================
   V1.5 - cân lại vùng đề và vùng nộp code
   ========================= */

/* Mục tiêu: đề vừa đủ đọc, bên phải rộng hơn để thấy ngày giờ/xem code/xóa code */

.problem-layout-large {
    grid-template-columns: minmax(600px, 1.35fr) minmax(460px, .95fr) !important;
    gap: 20px !important;
    align-items: start !important;
}

.problem-statement {
    min-width: 0;
}

.submit-side {
    min-width: 430px;
}

.pdf-frame,
.pdf-frame-large,
.pdf-frame-balanced {
    height: calc(100vh - 190px) !important;
    min-height: 720px !important;
    max-height: 860px !important;
}

/* Thanh nút đề bài nổi bật hơn */
.problem-toolbar {
    background: #ffffff;
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 12px 14px;
    box-shadow: 0 6px 18px rgba(13, 110, 253, 0.08);
}

.large-statement-btn {
    background: linear-gradient(135deg, #0d6efd, #084298);
    color: #ffffff;
    border: none;
    border-radius: 12px;
    padding: 13px 20px;
    font-size: 17px;
    font-weight: 900;
    letter-spacing: .2px;
    box-shadow: 0 10px 24px rgba(13, 110, 253, 0.28);
}

.large-statement-btn:hover {
    background: linear-gradient(135deg, #0b5ed7, #052c65);
    transform: translateY(-1px);
}

.secondary-open-btn {
    background: #eef6ff !important;
    color: var(--primary) !important;
    border: 1px solid #b9d7ff !important;
}

.pdf-size-note {
    color: var(--text-muted);
    font-size: 13px;
    font-weight: 700;
}

/* Bên phải cần nhìn rõ lịch sử nộp */
.submit-side .card {
    padding: 16px !important;
}

.submit-side .data-table th,
.submit-side .data-table td {
    padding: 10px 8px !important;
    font-size: 14px !important;
}

.submit-side .data-table td:first-child {
    min-width: 138px;
}

.submit-side .table-actions,
.submit-side form {
    margin: 0;
}

.no-margin-btn {
    padding: 7px 10px !important;
    font-size: 13px !important;
}

/* Code input đủ rộng, nhưng không chiếm quá nhiều chiều cao */
.code-input {
    min-height: 240px !important;
    height: 30vh;
    max-height: 420px;
    font-family: Consolas, "Courier New", monospace;
}

/* Khi mở đề lớn vẫn dùng toàn màn hình như V1.4 */
.statement-focus-layout .pdf-frame,
.statement-focus-layout .pdf-frame-large,
.statement-focus-layout .pdf-frame-balanced {
    height: calc(100vh - 72px) !important;
    min-height: calc(100vh - 72px) !important;
    max-height: none !important;
}

/* Màn hình vừa thì vẫn ưu tiên hai cột nếu đủ, nếu không chuyển một cột */
@media (max-width: 1320px) {
    .problem-layout-large {
        grid-template-columns: minmax(560px, 1.25fr) minmax(390px, .9fr) !important;
        gap: 16px !important;
    }

    .submit-side {
        min-width: 380px;
    }

    .pdf-frame,
    .pdf-frame-large,
    .pdf-frame-balanced {
        min-height: 650px !important;
        height: calc(100vh - 210px) !important;
    }
}

@media (max-width: 1120px) {
    .problem-layout-large {
        grid-template-columns: 1fr !important;
    }

    .submit-side {
        min-width: 0;
    }

    .pdf-frame,
    .pdf-frame-large,
    .pdf-frame-balanced {
        min-height: 640px !important;
        height: 72vh !important;
        max-height: none !important;
    }
}


/* =========================
   V1.6 - Themis queue + đọc log chi tiết test
   ========================= */

.themis-log-card {
    border-left: 7px solid var(--primary);
}

.log-scan-btn {
    background: linear-gradient(135deg, #0d6efd, #084298) !important;
    box-shadow: 0 8px 18px rgba(13, 110, 253, 0.22);
}

.themis-queue-hint {
    font-size: 14px;
    margin-bottom: 12px;
}

.status-queued {
    background: #eef6ff;
    color: #0d6efd;
}

.status-judging {
    background: #fff7ed;
    color: #c2410c;
}

.tests-card .data-table td:last-child {
    white-space: pre-wrap;
}


/* =========================
   V1.7 - quản lý bài/kỳ thi/test nâng cao
   ========================= */
.action-cell { display:flex; gap:6px; flex-wrap:wrap; align-items:center; }
.inline-form { display:inline-block; margin:4px; }
.inline-form button { border:none; background:transparent; color:#b91c1c; font-weight:900; cursor:pointer; }
.checkbox-line { display:flex; gap:8px; align-items:center; font-weight:700; }
.narrow-card { max-width:560px; margin:auto; }
.io-box { background:#f8fafc; color:#0f172a; border:1px solid #dbeafe; border-radius:10px; padding:10px; white-space:pre-wrap; max-height:260px; overflow:auto; }
select[multiple] { min-height:150px; }
small { color: var(--text-muted); }


/* =========================
   V1.8 - bố trí form khoa học hơn
   ========================= */

.form-section-title {
    margin: 18px 0 10px;
    padding-left: 10px;
    border-left: 5px solid var(--primary);
    color: var(--primary);
    font-weight: 900;
    font-size: 16px;
}

.compact-grid {
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)) !important;
    gap: 14px 16px !important;
}

.narrow-card {
    max-width: 860px;
}

.action-cell {
    min-width: 260px;
}

.action-cell .small-link-btn,
.action-cell form,
.table-actions form,
.table-actions .small-link-btn {
    margin: 2px 3px 2px 0;
}

.table-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    align-items: center;
}

.secondary-btn {
    background: #eef6ff !important;
    color: var(--primary) !important;
    border: 1px solid #b9d7ff !important;
}

/* V1.9 - hướng dẫn thư mục test rõ hơn */
.folder-sample {
    background: #f8fafc;
    border: 1px solid #dbeafe;
    border-left: 5px solid var(--primary);
    border-radius: 10px;
    padding: 12px 14px;
    overflow-x: auto;
    color: #111827;
    font-size: 14px;
}


/* V2.2 - test detail and live judge progress */
.test-detail-row td { background: #f8fbff; }
.test-detail-box { padding: 10px; border: 1px solid #dbeafe; border-radius: 12px; background: #ffffff; }
.mini-test-table { width: 100%; border-collapse: collapse; margin-top: 8px; font-size: 13px; }
.mini-test-table th, .mini-test-table td { border-bottom: 1px solid #e5e7eb; padding: 7px 8px; text-align: left; vertical-align: top; }
.verdict { display: inline-block; padding: 3px 8px; border-radius: 999px; font-weight: 700; font-size: 12px; background: #e5e7eb; color: #374151; }
.verdict-ac { background: #dcfce7; color: #166534; }
.verdict-wa, .verdict-no_output { background: #fee2e2; color: #991b1b; }
.verdict-tle { background: #fef3c7; color: #92400e; }
.verdict-re, .verdict-ce, .verdict-judge_error, .verdict-checker_error { background: #ffedd5; color: #9a3412; }
.judging-card { max-width: 900px; }
.judge-progress-wrap { width: 100%; height: 22px; background: #e5e7eb; border-radius: 999px; overflow: hidden; margin: 10px 0; }
.judge-progress-bar { height: 100%; background: linear-gradient(90deg, #2563eb, #22c55e); transition: width .25s ease; }
.judge-progress-text { font-weight: 700; color: #0f172a; margin-top: 8px; }
.judge-progress-meta { color: #64748b; margin-top: 4px; }
.link-as-button { text-decoration: none; display: inline-flex; align-items: center; justify-content: center; }


/* V2.4 - Bảng xếp hạng kiểu kỳ thi */
.scoreboard-wrap {
    width: 100%;
    overflow-x: auto;
    border-radius: 12px;
    border: 1px solid #cbd5e1;
}
.scoreboard-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 980px;
    background: #fff;
}
.scoreboard-table th {
    background: #12304a;
    color: #fff;
    border: 1px solid rgba(255,255,255,0.25);
    padding: 9px 10px;
    text-align: center;
    font-weight: 700;
}
.scoreboard-table th a { color: #fff; text-decoration: none; display: block; }
.scoreboard-table td {
    border: 1px solid #d1d5db;
    padding: 9px 10px;
    text-align: center;
    vertical-align: middle;
}
.scoreboard-table tbody tr:nth-child(even) { background: #f8fafc; }
.scoreboard-table tbody tr:hover { background: #eef6ff; }
.rank-col { width: 64px; }
.student-col { min-width: 260px; }
.total-col { width: 92px; }
.problem-col { min-width: 76px; }
.rank-cell { font-weight: 700; font-size: 16px; }
.student-cell { text-align: left !important; }
.student-username { font-weight: 800; color: #0f766e; }
.student-name { color: #64748b; font-size: 12px; margin-top: 3px; }
.total-cell a, .score-cell a { font-weight: 800; color: #075985; text-decoration: none; }
.total-cell a:hover, .score-cell a:hover { text-decoration: underline; }
.score-cell { min-width: 76px; }
.score-ac { background: #b9f99c !important; }
.score-partial { background: #fffbe6; }
.cell-time { display: block; color: #6b7280; font-size: 11px; margin-top: 3px; white-space: nowrap; }
.muted { color: #9ca3af; }
.info-table { width: 100%; border-collapse: collapse; margin-top: 10px; }
.info-table th, .info-table td { border: 1px solid #d1d5db; padding: 10px; text-align: left; }
.info-table th { width: 220px; background: #f1f5f9; color: #0f172a; }
.small-input{max-width:90px;padding:7px 8px;border:1px solid #cbd5e1;border-radius:8px;}
.warning{background:#fff7ed;border-color:#fed7aa;color:#9a3412;}


/* =========================
   V2.8 - giao diện test/kỳ thi thân thiện hơn
   ========================= */
.hide-test-head,
.hide-test-cell {
    text-align: center !important;
    vertical-align: middle !important;
    width: 92px;
}
.hide-test-title {
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 7px;
    line-height: 1.15;
}
.hide-test-head input[type="checkbox"],
.hide-test-cell input[type="checkbox"] {
    width: 16px !important;
    height: 16px !important;
    display: inline-block !important;
    margin: 0 auto !important;
    padding: 0 !important;
}
.centered-form label {
    text-align: center;
    width: 100%;
    color: #0f3f7a;
}
.centered-form input,
.centered-form select {
    text-align: center;
}
.contest-time-grid {
    grid-template-columns: repeat(4, minmax(210px, 1fr)) !important;
}
.contest-access-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)) !important;
}
.contest-permission-grid {
    grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)) !important;
}
.practice-problem-card {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 14px;
    align-items: center;
}
.practice-meta {
    color: var(--text-muted);
    font-size: 14px;
    margin-top: 5px;
}
@media(max-width:1000px){
    .contest-time-grid,
    .contest-access-grid,
    .contest-permission-grid,
    .practice-problem-card {
        grid-template-columns: 1fr !important;
    }
}

/* V2.9 - giao diện làm bài/nộp bài và thao tác bảng */
.contest-action-cell{display:flex;gap:8px;align-items:center;justify-content:flex-start;flex-wrap:nowrap}.contest-action-cell form{margin:0}.contest-action-cell .small-btn,.contest-action-cell .small-link-btn{min-width:86px;text-align:center;margin-top:0}.problem-read-layout{grid-template-columns:minmax(860px,2.7fr) minmax(250px,.55fr)!important}.compact-submit-side{max-width:330px}.problem-info-card{position:sticky;top:18px}.big-submit-btn{width:100%;padding:16px 18px;border-radius:12px;background:var(--success);color:#fff;font-weight:900;font-size:18px;box-shadow:0 8px 20px rgba(25,135,84,.22)}.big-submit-btn:hover{filter:brightness(.96)}.big-submit-btn:disabled{background:#94a3b8;cursor:not-allowed;box-shadow:none}.compact-info-table td{padding:9px 6px!important}.compact-info-table td:first-child{width:42%;color:var(--text-muted);font-weight:700}.compact-info-table code{font-size:13px}.compact-hint{font-size:14px;margin-top:10px;padding:10px}.submit-panel{border-left:6px solid var(--success)}.submit-top-line{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin-bottom:10px}.submit-top-line input[type=file]{width:auto;min-width:260px}.inline-label{display:inline-block;margin:0;font-weight:800}.hint-inline{color:var(--text-muted);font-size:14px}.code-input-large{min-height:520px!important;font-family:Consolas,"Courier New",monospace;font-size:15px;line-height:1.45}.submit-final-row{justify-content:flex-end}.big-final-submit{font-size:17px;padding:12px 22px!important;background:var(--success)!important}.stat-card .stat-number{line-height:1}.status-text-ac{color:var(--success);font-weight:800}.status-text-bad{color:var(--danger);font-weight:800}.action-cell form{display:inline-block}.action-cell .small-btn,.action-cell .small-link-btn{margin-top:0}@media(max-width:1300px){.problem-read-layout{grid-template-columns:1fr!important}.compact-submit-side{max-width:none}.problem-info-card{position:static}.code-input-large{min-height:420px!important}.contest-action-cell{flex-wrap:wrap}}


/* =========================
   V3.0 - Code editor, dashboard, logs
   ========================= */
.oj-code-editor{display:grid;grid-template-columns:58px 1fr;border:1px solid #cfe0f5;border-radius:14px;background:#0f172a;overflow:hidden;box-shadow:inset 0 0 0 1px rgba(255,255,255,.04)}
.oj-code-gutter{margin:0;padding:14px 10px;background:#eaf2ff;color:#64748b;text-align:right;line-height:1.55;font-family:Consolas,'Courier New',monospace;font-size:14px;user-select:none;overflow:hidden;border-right:1px solid #cfe0f5;min-height:420px;white-space:pre}
.oj-code-stack{position:relative;min-height:420px;background:#0f172a;overflow:hidden}.oj-code-highlight,.oj-code-textarea-ready{margin:0;padding:14px 16px!important;font-family:Consolas,'Courier New',monospace!important;font-size:15px!important;line-height:1.55!important;tab-size:4;white-space:pre!important;box-sizing:border-box;width:100%;min-height:420px;border:0!important;border-radius:0!important;overflow:auto!important}.oj-code-highlight{position:absolute;inset:0;color:#e5e7eb;pointer-events:none;background:#0f172a;z-index:1}.oj-code-textarea-ready{position:absolute!important;inset:0!important;background:transparent!important;color:rgba(255,255,255,.01)!important;-webkit-text-fill-color:rgba(255,255,255,.01)!important;caret-color:#ffffff!important;resize:vertical;outline:0;z-index:2;pointer-events:auto!important;user-select:text!important}.oj-code-textarea-ready:focus{box-shadow:inset 0 0 0 2px rgba(96,165,250,.35)}.oj-code-textarea-ready::selection{background:rgba(96,165,250,.35);color:rgba(255,255,255,.01)}.tok-key{color:#93c5fd;font-weight:700}.tok-lib{color:#67e8f9}.tok-string{color:#86efac}.tok-comment{color:#94a3b8;font-style:italic}.tok-pre{color:#fbbf24}.tok-num{color:#fca5a5}.oj-readonly-wrap{display:grid;grid-template-columns:58px 1fr;border:1px solid #cfe0f5;border-left:7px solid var(--primary);border-radius:12px;overflow:auto;background:#0f172a;max-height:72vh}.oj-readonly-gutter{min-height:auto;background:#eaf2ff}.oj-readonly-highlight{margin:0;padding:14px 16px;color:#e5e7eb;background:#0f172a;line-height:1.55;font-family:Consolas,'Courier New',monospace;font-size:15px;white-space:pre;tab-size:4;min-width:max-content}.editor-tip{font-size:13px;color:#64748b;margin:6px 0 10px}.dashboard-table-compact th,.dashboard-table-compact td{font-size:14px;padding:9px 8px}.log-action{font-weight:900;color:var(--primary)}.restore-warning{border-left:5px solid var(--warning);background:#fff8e1;padding:12px 14px;border-radius:10px;margin:12px 0}.stat-card b{font-size:30px;color:var(--primary);display:block}.stat-card span{font-weight:800;color:#64748b}.code-input-large{min-height:420px!important}

.oj-code-textarea-ready::placeholder{color:#94a3b8!important;-webkit-text-fill-color:#94a3b8!important;}


/* V3.0.2: editor nộp bài ưu tiên sửa code chắc chắn.
   Không dùng lớp highlight phủ lên textarea nữa, textarea hiển thị trực tiếp và luôn editable. */
.oj-code-editor-plain{
    display:grid!important;
    grid-template-columns:58px minmax(0,1fr)!important;
    border:1px solid #cfe0f5!important;
    border-radius:14px!important;
    background:#0f172a!important;
    overflow:hidden!important;
    box-shadow:inset 0 0 0 1px rgba(255,255,255,.04)!important;
}
.oj-code-editor-plain.is-focused{
    box-shadow:0 0 0 3px rgba(37,99,235,.18), inset 0 0 0 1px rgba(255,255,255,.05)!important;
}
.oj-code-editor-plain .oj-code-gutter-edit{
    margin:0!important;
    padding:14px 10px!important;
    background:#eaf2ff!important;
    color:#64748b!important;
    text-align:right!important;
    line-height:1.55!important;
    font-family:Consolas,'Courier New',monospace!important;
    font-size:14px!important;
    user-select:none!important;
    overflow:hidden!important;
    border-right:1px solid #cfe0f5!important;
    white-space:pre!important;
    min-height:0!important;
}
.oj-code-textarea-plain,
.oj-code-editor-plain textarea.oj-code-textarea-ready{
    position:static!important;
    inset:auto!important;
    z-index:auto!important;
    display:block!important;
    margin:0!important;
    padding:14px 16px!important;
    width:100%!important;
    min-height:180px!important;
    height:auto;
    border:0!important;
    border-radius:0!important;
    background:#0f172a!important;
    color:#e5e7eb!important;
    -webkit-text-fill-color:#e5e7eb!important;
    caret-color:#ffffff!important;
    resize:vertical!important;
    outline:0!important;
    box-sizing:border-box!important;
    font-family:Consolas,'Courier New',monospace!important;
    font-size:15px!important;
    line-height:1.55!important;
    tab-size:4!important;
    white-space:pre!important;
    pointer-events:auto!important;
    user-select:text!important;
}
.oj-code-editor-plain textarea.oj-code-textarea-ready::selection{
    background:rgba(96,165,250,.40)!important;
    color:#fff!important;
    -webkit-text-fill-color:#fff!important;
}
.oj-code-editor-plain textarea.oj-code-textarea-ready::placeholder{
    color:#94a3b8!important;
    -webkit-text-fill-color:#94a3b8!important;
}
.code-input-large{min-height:180px!important;}
.editor-tip::after{content:' Editor ưu tiên sửa trực tiếp trong ô code; code dài đến đâu khung tự cao đến đó, không tạo nhiều dòng trống.';}


/* =========================
   V3.0.3 - Editor nộp bài có highlight, sửa trực tiếp được
   ========================= */
.oj-hidden-source{
    display:none!important;
}
.oj-code-editor-rich{
    display:grid!important;
    grid-template-columns:58px minmax(0,1fr)!important;
    height:560px!important;
    min-height:520px!important;
    max-height:72vh!important;
    border:1px solid #cfe0f5!important;
    border-radius:14px!important;
    background:#0f172a!important;
    overflow:hidden!important;
    box-shadow:inset 0 0 0 1px rgba(255,255,255,.04)!important;
}
.oj-code-editor-rich.is-focused{
    box-shadow:0 0 0 3px rgba(37,99,235,.18), inset 0 0 0 1px rgba(255,255,255,.06)!important;
}
.oj-code-editor-rich .oj-code-gutter-edit{
    height:100%!important;
    min-height:0!important;
    margin:0!important;
    padding:14px 10px!important;
    background:#eaf2ff!important;
    color:#64748b!important;
    text-align:right!important;
    line-height:1.55!important;
    font-family:Consolas,'Courier New',monospace!important;
    font-size:var(--oj-editor-font-size,14px)!important;
    user-select:none!important;
    overflow:hidden!important;
    border-right:1px solid #cfe0f5!important;
    white-space:pre!important;
}
.oj-code-editable{
    height:100%!important;
    overflow:auto!important;
    margin:0!important;
    padding:14px 16px!important;
    background:#0f172a!important;
    color:#e5e7eb!important;
    outline:none!important;
    font-family:Consolas,'Courier New',monospace!important;
    font-size:var(--oj-editor-font-size,14px)!important;
    line-height:1.55!important;
    tab-size:4!important;
    white-space:pre!important;
    min-width:0!important;
    box-sizing:border-box!important;
    caret-color:#ffffff!important;
}
.oj-code-editable::selection,
.oj-code-editable *::selection{
    background:rgba(96,165,250,.42)!important;
    color:#ffffff!important;
}
.oj-code-editable:empty::before{
    content:'Dán code C++ hoặc chọn file .cpp ở trên...';
    color:#94a3b8;
}
.oj-code-editable .tok-key{color:#93c5fd!important;font-weight:700!important;}
.oj-code-editable .tok-lib{color:#67e8f9!important;}
.oj-code-editable .tok-string{color:#86efac!important;}
.oj-code-editable .tok-comment{color:#94a3b8!important;font-style:italic!important;}
.oj-code-editable .tok-pre{color:#fbbf24!important;}
.oj-code-editable .tok-num{color:#fca5a5!important;}
.editor-tip::after{content:' Editor có số dòng, tô màu C++, Enter xuống dòng bình thường. Ctrl + Enter để nộp nhanh.'!important;}
@media(max-width:1000px){.oj-code-editor-rich{height:480px!important;max-height:70vh!important;}}


/* V3.1 admin layout refinements */
.page-actions{display:flex;gap:12px;align-items:center;justify-content:flex-start;margin-bottom:16px;flex-wrap:wrap}.page-main-btn,.page-secondary-btn{min-width:170px;text-align:center;text-decoration:none}.admin-list-table th,.admin-list-table td{vertical-align:middle}.equal-action-cell{display:grid;grid-template-columns:repeat(4,minmax(92px,1fr));gap:6px;align-items:center;min-width:420px}.equal-action-cell form{margin:0}.equal-action-btn{width:100%;min-height:34px;display:inline-flex!important;align-items:center;justify-content:center;text-align:center;box-sizing:border-box;white-space:nowrap}.problem-form-main .form-section-title,.contest-form-main .form-section-title{margin-top:18px}.problem-main-grid,.contest-info-grid{grid-template-columns:repeat(5,minmax(150px,1fr))}.contest-time-grid{grid-template-columns:repeat(4,minmax(170px,1fr))}.contest-action-grid{grid-template-columns:repeat(3,minmax(180px,1fr))}.center-cell{text-align:center}.narrow-card{max-width:760px;margin-left:auto;margin-right:auto}.test-upload-form{margin:14px 0 18px}.test-replace-line{margin-top:6px}.hide-test-head,.hide-test-cell{text-align:center}.hide-test-title{color:#0b6bbf;font-weight:700;margin-bottom:4px}@media(max-width:1000px){.problem-main-grid,.contest-info-grid,.contest-time-grid,.contest-action-grid{grid-template-columns:1fr 1fr}.equal-action-cell{grid-template-columns:1fr 1fr;min-width:260px}}@media(max-width:650px){.problem-main-grid,.contest-info-grid,.contest-time-grid,.contest-action-grid{grid-template-columns:1fr}.equal-action-cell{grid-template-columns:1fr}}


/* V3.1.1 - chỉnh lại bố cục tạo/sửa bài và kỳ thi theo góp ý */
.problem-judge-grid,
.problem-file-grid,
.contest-info-grid,
.contest-permission-grid{
    grid-template-columns:repeat(5,minmax(150px,1fr))!important;
}
.contest-time-grid{
    grid-template-columns:repeat(4,minmax(190px,1fr))!important;
}
.contest-problem-table th{
    text-align:center!important;
    vertical-align:middle!important;
}
.contest-problem-table td{
    vertical-align:middle!important;
}
.contest-problem-table td:nth-child(2),
.contest-problem-table td:nth-child(3),
.contest-problem-table td:nth-child(4),
.contest-problem-table td:nth-child(5){
    text-align:center!important;
}
.contest-problem-table input,
.contest-problem-table select{
    text-align:center!important;
}
.contest-problem-table td:first-child select{
    text-align:left!important;
}
.problem-form-main .form-grid > div,
.contest-form-main .form-grid > div{
    min-width:0;
}
.problem-form-main label,
.contest-form-main label{
    min-height:34px;
    display:flex;
    align-items:flex-end;
    justify-content:center;
}
@media(max-width:1280px){
    .problem-judge-grid,
    .problem-file-grid,
    .contest-info-grid,
    .contest-permission-grid{grid-template-columns:repeat(3,minmax(170px,1fr))!important;}
}
@media(max-width:900px){
    .problem-judge-grid,
    .problem-file-grid,
    .contest-info-grid,
    .contest-permission-grid,
    .contest-time-grid{grid-template-columns:1fr 1fr!important;}
}
@media(max-width:650px){
    .problem-judge-grid,
    .problem-file-grid,
    .contest-info-grid,
    .contest-permission-grid,
    .contest-time-grid{grid-template-columns:1fr!important;}
}


/* V3.1.2 - bố cục form kỳ thi theo góp ý: mục 1/2 có 4 ô, mục 3 có 8 ô = 2 hàng */
.contest-form-main .contest-time-grid,
.contest-form-main .contest-info-grid,
.contest-form-main .contest-permission-grid{
    grid-template-columns:repeat(4,minmax(170px,1fr))!important;
}
@media(max-width:1100px){
    .contest-form-main .contest-time-grid,
    .contest-form-main .contest-info-grid,
    .contest-form-main .contest-permission-grid{
        grid-template-columns:repeat(2,minmax(170px,1fr))!important;
    }
}
@media(max-width:650px){
    .contest-form-main .contest-time-grid,
    .contest-form-main .contest-info-grid,
    .contest-form-main .contest-permission-grid{
        grid-template-columns:1fr!important;
    }
}


/* =========================
   V3.1.3 - chỉnh tổng quan và thêm học sinh
   ========================= */
.dashboard-summary{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:16px;
  margin-bottom:18px;
}
.summary-card{
  background:#fff;
  border:1px solid var(--border);
  border-radius:16px;
  padding:20px 22px;
  box-shadow:0 4px 14px rgba(13,110,253,.06);
  min-height:108px;
  display:flex;
  flex-direction:column;
  justify-content:center;
}
.summary-card span{
  color:var(--text-muted);
  font-weight:800;
  margin-bottom:8px;
}
.summary-card b{
  color:var(--primary);
  font-size:34px;
  line-height:1;
}
.today-overview-card{
  margin-bottom:22px;
}
.today-chart{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:18px;
  align-items:end;
  min-height:170px;
}
.today-item{
  display:grid;
  grid-template-columns:64px 1fr;
  grid-template-rows:auto auto;
  align-items:end;
  gap:4px 14px;
  padding:14px;
  background:#f8fbff;
  border:1px solid var(--border);
  border-radius:14px;
  min-height:150px;
}
.today-bar-wrap{
  grid-row:1/3;
  width:46px;
  height:112px;
  border-radius:14px;
  background:#eaf3ff;
  display:flex;
  align-items:flex-end;
  justify-content:center;
  overflow:hidden;
  border:1px solid #d6e4f5;
}
.today-bar{
  width:100%;
  min-height:6px;
  border-radius:14px 14px 0 0;
  background:var(--primary);
  transition:height .2s ease;
}
.today-bar-ac{background:var(--success)}
.today-bar-ce{background:var(--danger)}
.today-value{
  font-size:32px;
  color:var(--primary);
  font-weight:900;
  line-height:1;
}
.today-label{
  color:var(--text-muted);
  font-weight:800;
}
.student-add-grid{
  display:grid;
  grid-template-columns:2fr 1fr 1.2fr 1.2fr;
  gap:14px 18px;
  align-items:end;
}
.compact-hint-box{
  margin-top:14px!important;
}
@media(max-width:1100px){
  .dashboard-summary,.today-chart,.student-add-grid{grid-template-columns:1fr}
  .today-item{grid-template-columns:56px 1fr}
}


/* V3.1.5 - chỉnh Cấu hình chấm và bộ lọc Bài tập tự luyện */
.settings-grid-4 {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px 16px;
    align-items: end;
    margin-bottom: 16px;
}
.practice-filter-grid {
    display: grid;
    grid-template-columns: 1.2fr 1.2fr 1.5fr auto;
    gap: 14px 16px;
    align-items: end;
}
.filter-actions {
    display: flex;
    gap: 8px;
    align-items: center;
    justify-content: flex-start;
    padding-top: 18px;
}
.filter-actions .form-submit-btn,
.filter-actions .small-link-btn {
    margin-top: 0;
    white-space: nowrap;
}
.practice-summary-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 14px;
}
.practice-summary-row span {
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 999px;
    padding: 7px 12px;
    font-weight: 700;
}
@media(max-width:1200px){
    .settings-grid-4,
    .practice-filter-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .filter-actions { justify-content: flex-start; }
}
@media(max-width:720px){
    .settings-grid-4,
    .practice-filter-grid { grid-template-columns: 1fr; }
}

/* V3.1.7 - xếp hạng tự luyện theo điểm độ khó */
.student-home-card h3{
    margin:8px 0 6px;
    color:var(--primary-dark);
}
.student-home-card p{
    min-height:44px;
    margin:0 0 10px;
    color:var(--text-muted);
    line-height:1.45;
}
.ranking-stats-grid .stat-card{
    min-height:132px;
}
.ranking-table th,
.ranking-table td{
    text-align:center!important;
}
.ranking-table td:nth-child(3){
    text-align:left!important;
}
@media(max-width:1200px){
    .student-home-grid,
    .ranking-stats-grid{grid-template-columns:repeat(2,minmax(0,1fr))!important;}
}
@media(max-width:720px){
    .student-home-grid,
    .ranking-stats-grid{grid-template-columns:1fr!important;}
}

/* V3.2 modular: bulk management + editor controls */
.bulk-action-row { align-items:center; gap:8px; margin:12px 0; flex-wrap:wrap; }
.pagination-row { justify-content:center; align-items:center; gap:12px; margin-top:14px; flex-wrap:wrap; }
.editor-toolbar-row { justify-content:space-between; align-items:end; margin-bottom:6px; }
.editor-toolbar-row select { min-width:92px; }
.data-table input[type="checkbox"] { width:18px; height:18px; cursor:pointer; }

/* V3.6 - presence, logs, backup */
.presence-dot{display:inline-block;width:14px;height:14px;border-radius:50%;box-shadow:0 0 0 3px rgba(0,0,0,.04)}
.presence-online{background:#22c55e}.presence-contest{background:#2563eb}.presence-practice{background:#9333ea}.presence-judging{background:#eab308}.presence-offline{background:#94a3b8}
.presence-table td:first-child,.presence-table th:first-child{text-align:center;width:84px}
.student-online-widget{position:relative;margin-left:auto;margin-right:14px}.student-online-widget summary{cursor:pointer;font-weight:800;color:#15803d;list-style:none}.student-online-popup{position:absolute;right:0;top:34px;z-index:40;background:#fff;border:1px solid var(--border);border-radius:12px;box-shadow:0 12px 30px rgba(0,0,0,.12);padding:10px 14px;min-width:240px;max-height:320px;overflow:auto}.student-online-popup div{padding:7px 0;border-bottom:1px solid #eef2f7}.student-online-popup span{color:var(--text-muted);font-size:12px}
.log-level-warning{background:#fef3c7;color:#92400e}.log-level-error{background:#fee2e2;color:#991b1b}.log-level-info{background:#e0f2fe;color:#075985}.log-detail{padding:10px 0;line-height:1.6}
.presence-scroll{max-height:420px;overflow:auto;border-radius:10px}.presence-scroll .data-table{margin-bottom:0}.presence-scroll thead th{position:sticky;top:0;background:#f8fafc;z-index:2}

/* V3.10 - Online friendly admin */
.online-prepare-row{display:flex;gap:14px;align-items:end;flex-wrap:wrap}.online-contest-select{flex:1;min-width:280px}.online-status-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:10px}.online-status-card{display:flex;gap:10px;align-items:flex-start;padding:12px;border:1px solid #e5e7eb;border-radius:10px}.online-status-card.status-ok{background:#f0fdf4}.online-status-card.status-warning{background:#fffbeb}.online-status-card.status-error{background:#fef2f2}.online-status-icon{width:28px;height:28px;border-radius:50%;display:flex;align-items:center;justify-content:center;background:#fff;font-weight:800}.online-dashboard-stats{display:grid!important;grid-template-columns:repeat(5,minmax(0,1fr))!important;gap:10px}.online-dashboard-stats .stat-card{min-width:0}@media(max-width:900px){.online-dashboard-stats{grid-template-columns:repeat(2,minmax(0,1fr))!important}}@media(max-width:520px){.online-dashboard-stats{grid-template-columns:1fr!important}}
.contest-prefix-row{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-top:8px}.contest-prefix-row input{flex:1;min-width:260px}.prefix-results{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:6px;margin-top:10px;max-height:240px;overflow:auto}.prefix-problem-item{display:block;padding:8px 10px;background:#fff;border:1px solid #e5e7eb;border-radius:8px;cursor:pointer}.prefix-problem-item:hover{background:#f8fafc}


/* V3.10 round 2 - bố cục lọc và giao kỳ thi đã chốt */
.submissions-filter-grid{
  grid-template-columns:1.35fr .9fr .75fr 1.55fr .9fr .75fr!important;
  align-items:end;
}
.contest-assignment-grid{grid-template-columns:1fr 1.4fr!important;}
.contest-all-students{display:flex;align-items:center;gap:8px;margin:12px 0 2px;font-weight:800;}
.contest-all-students input{width:auto;margin:0;}
@media(max-width:1250px){.submissions-filter-grid{grid-template-columns:repeat(3,minmax(180px,1fr))!important;}}
@media(max-width:800px){.submissions-filter-grid,.contest-assignment-grid{grid-template-columns:1fr!important;}}


/* V3.10 UX patch - dashboard ngang + giao kỳ thi */
.online-sync-stats{display:grid!important;grid-template-columns:repeat(6,minmax(0,1fr))!important;gap:10px}.online-sync-stats .stat-card{min-width:0;padding:16px}.online-sync-stats .stat-card b{font-size:27px}.online-sync-stats .stat-card small{display:block;margin-top:5px;color:var(--text-muted)}
.assignment-hero-card{border-left:5px solid var(--primary)}.assignment-summary-row{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-top:14px}.assignment-summary-row>div{background:#f8fbff;border:1px solid var(--border);border-radius:12px;padding:14px}.assignment-summary-row span,.assignment-summary-row small{display:block;color:var(--text-muted);font-weight:700}.assignment-summary-row b{display:block;color:var(--primary);font-size:28px;margin:5px 0}.assignment-all-toggle{display:flex;gap:14px;align-items:center;margin:0;cursor:pointer}.assignment-all-toggle input{width:22px;height:22px;flex:0 0 auto}.assignment-all-toggle span{display:flex;flex-direction:column;gap:4px}.assignment-all-toggle b{font-size:18px}.assignment-all-toggle small{color:var(--text-muted)}.assignment-grid{display:grid;grid-template-columns:minmax(300px,.75fr) minmax(520px,1.25fr);gap:16px}.assignment-section-card{min-height:480px}.assignment-class-list,.assignment-student-list{display:grid;gap:8px;max-height:520px;overflow:auto;padding-right:4px}.assignment-class-list{grid-template-columns:repeat(2,minmax(0,1fr))}.assignment-student-list{grid-template-columns:repeat(2,minmax(0,1fr))}.assignment-choice{display:flex;align-items:center;gap:10px;border:1px solid var(--border);border-radius:10px;padding:10px 12px;margin:0;cursor:pointer;background:#fff}.assignment-choice:hover{background:var(--primary-light)}.assignment-choice input{width:18px;height:18px;flex:0 0 auto}.assignment-choice span{min-width:0;display:flex;flex-direction:column;gap:3px}.assignment-choice b{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.assignment-choice small{color:var(--text-muted)}.assignment-choice.covered-by-class{background:#eef7ff;border-color:#a9cdf7}.assignment-choice.covered-by-class:after{content:'Theo lớp';margin-left:auto;color:var(--primary);font-size:12px;font-weight:800}.assignment-search-row{display:grid;grid-template-columns:1fr auto auto;gap:8px;align-items:end;margin-bottom:12px}.assignment-search-row .small-btn,.compact-actions .small-btn{margin-top:0}.assignment-save-card{position:sticky;bottom:10px;display:flex;justify-content:space-between;align-items:center;gap:16px;z-index:5;border-left:5px solid var(--success)}.assignment-save-summary{display:flex;flex-direction:column;gap:4px}.assignment-save-summary span{color:var(--text-muted)}.assignment-all-active .assignment-section-card{opacity:.6}.assignment-all-active .assignment-section-card input{pointer-events:none}.assignment-summary-card{border-left:5px solid var(--primary)}
@media(max-width:1200px){.online-sync-stats{grid-template-columns:repeat(3,minmax(0,1fr))!important}.assignment-grid{grid-template-columns:1fr}.assignment-section-card{min-height:0}}
@media(max-width:800px){.online-sync-stats{grid-template-columns:repeat(2,minmax(0,1fr))!important}.assignment-summary-row,.assignment-class-list,.assignment-student-list{grid-template-columns:1fr}.assignment-search-row{grid-template-columns:1fr}.assignment-save-card{position:static;flex-direction:column;align-items:stretch}}
@media(max-width:520px){.online-sync-stats{grid-template-columns:1fr!important}}

/* V3.10 UX chốt 18-08-2026: điều hướng cố định trong kỳ thi */
.contest-sidebar-menu{display:flex;flex-direction:column;min-height:0;height:calc(100vh - 105px)}
.contest-exit-btn{background:#64748b!important;color:#fff!important;text-align:center}
.contest-scoreboard-btn{background:#f59e0b!important;color:#fff!important;text-align:center}
.contest-sidebar-heading{margin:12px 3px 8px;padding:10px 11px;border:1px solid var(--border);border-radius:10px;background:#f8fbff;display:flex;flex-direction:column;gap:3px}
.contest-sidebar-heading b{color:var(--primary-dark);font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.contest-sidebar-heading span{font-size:12px;color:var(--text-muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.contest-problem-list{display:flex;flex-direction:column;gap:7px;overflow-y:auto;overscroll-behavior:contain;padding:2px 4px 12px 1px;min-height:0;scrollbar-width:thin}
.contest-problem-nav-item{display:flex;flex-direction:column;gap:4px;padding:9px 10px;border:1px solid var(--border);border-radius:10px;background:#fff;color:var(--text-main);transition:.15s ease}
.contest-problem-nav-item:hover{background:var(--primary-light);border-color:#9bc4f6;color:var(--text-main)}
.contest-problem-nav-item.active{background:var(--primary);border-color:var(--primary);color:#fff;box-shadow:0 5px 14px rgba(13,110,253,.2)}
.contest-problem-nav-main{display:flex;align-items:center;justify-content:space-between;gap:8px;min-width:0}
.contest-problem-nav-main b{font-size:14px;white-space:nowrap}.contest-problem-nav-main small{font-size:11px;font-weight:800;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:110px}
.contest-problem-nav-status{font-size:12px;font-weight:800;color:var(--text-muted);white-space:normal;line-height:1.25}
.contest-problem-nav-item.active .contest-problem-nav-status,.contest-problem-nav-item.active small{color:#fff}
.contest-problem-nav-item.nav-full:not(.active){border-left:5px solid var(--success);background:#f0fdf4}.contest-problem-nav-item.nav-full:not(.active) .contest-problem-nav-status{color:var(--success)}
.contest-problem-nav-item.nav-partial:not(.active){border-left:5px solid #f59e0b;background:#fffbeb}.contest-problem-nav-item.nav-partial:not(.active) .contest-problem-nav-status{color:#a16207}
.contest-problem-nav-item.nav-judging:not(.active){border-left:5px solid #0ea5e9;background:#f0f9ff}.contest-problem-nav-item.nav-judging:not(.active) .contest-problem-nav-status{color:#0369a1}
.contest-problem-nav-item.nav-submitted:not(.active){border-left:5px solid #64748b}.contest-problem-nav-item.nav-not_started:not(.active){opacity:.92}
.contest-nav-empty{padding:16px 8px;text-align:center;color:var(--text-muted);font-size:13px}
@media(max-width:1000px){.contest-sidebar-menu{height:auto}.contest-problem-list{max-height:360px}.contest-sidebar-heading{margin-top:8px}}
.embedded-code-page{background:transparent!important;padding:0!important}.embedded-code-page .light-code-card{max-width:none!important;margin:0!important}

/* V3.10 authoritative/event UI 19-08-2026 */
.contest-problem-table{font-size:15.5px}.contest-problem-table th,.contest-problem-table td{padding:14px 13px!important;vertical-align:middle}.contest-problem-table td:nth-child(2) b{font-size:16px;color:var(--primary-dark)}.contest-problem-table td:nth-child(3){font-weight:650;line-height:1.45}
.submit-panel{width:min(100%,900px);max-width:100%;margin:0 auto 22px;padding:14px 16px!important;box-sizing:border-box;overflow:hidden}.submit-panel,.submit-panel input,.submit-panel select,.submit-panel button,.submit-panel label,.submit-panel span,.submit-panel .hint-box{font-family:inherit}.submit-panel form,.submit-panel .info-table{max-width:100%}.submit-top-line{min-width:0}.submit-top-line input[type=file]{width:auto;min-width:0;max-width:100%;flex:1 1 300px}.submit-panel .editor-toolbar-row{gap:10px;flex-wrap:wrap}.submit-panel .oj-code-textarea{max-width:100%;box-sizing:border-box}.code-input-large{font-size:14px;min-height:440px!important}.submit-final-row{gap:8px;flex-wrap:wrap}
@media(max-width:760px){.submit-panel{padding:12px!important}.submit-top-line{align-items:flex-start}.submit-top-line .inline-label{flex:1 0 100%}.code-input-large{min-height:360px!important}.contest-problem-table{font-size:14.5px}.contest-problem-table th,.contest-problem-table td{padding:11px 9px!important}}

/* V3.10 Online parity helpers - harmless on LAN, shared verbatim with Google portal */
.portal-toast{position:fixed;right:22px;bottom:22px;z-index:9999;max-width:430px;background:#fff;border:1px solid var(--border);border-left:5px solid var(--primary);box-shadow:0 12px 32px rgba(15,23,42,.18);border-radius:12px;padding:12px 16px;font-weight:800;line-height:1.4}
.portal-toast.ok{border-left-color:var(--success)}.portal-toast.error{border-left-color:var(--danger)}.portal-toast.warn{border-left-color:#f59e0b}
.judging-card .judge-progress-wrap{height:16px;background:#e9eef5;border-radius:999px;overflow:hidden;margin:16px 0}.judging-card .judge-progress-bar{height:100%;background:var(--primary);transition:width .25s ease}.judge-progress-text{font-size:18px;font-weight:800;margin:8px 0}.judge-progress-meta{color:var(--text-muted);margin-bottom:8px}
.sync-authoritative-box{font-size:16px;padding:18px}

/* =====================================================================
   V3.10.1 - LAN FAST + bố cục thi 3 cột đối xứng, an toàn khi zoom
   Chốt 19-08-2026
   ===================================================================== */
.problem-read-layout{
    grid-template-columns:minmax(0,1fr) var(--sidebar-width)!important;
    gap:18px!important;
    align-items:start!important;
    min-width:0;
}
.problem-main-column{min-width:0;width:100%}
.problem-main-column .problem-statement{width:100%;max-width:none;margin-left:0;margin-right:0}
.compact-submit-side{
    width:var(--sidebar-width)!important;
    min-width:0!important;
    max-width:var(--sidebar-width)!important;
    position:sticky;
    top:18px;
    align-self:start;
}
.compact-submit-side .problem-info-card{width:100%;position:static!important;margin:0}
/* Khung Gửi bài giải nằm cùng cột với Đề bài => hai mép rộng bằng nhau tuyệt đối. */
.problem-main-column .submit-panel{
    width:100%!important;
    max-width:none!important;
    margin:0 0 22px!important;
    overflow:hidden;
}
.problem-main-column .submit-panel form,
.problem-main-column .submit-panel .oj-code-textarea{width:100%;max-width:100%}
.problem-drawer-trigger,.problem-drawer-overlay{display:none}

/* Khi zoom lớn làm CSS viewport hẹp, không ép 3 cột tới mức che khung phải.
   Hai sidebar chuyển đồng thời thành drawer đối xứng. */
@media(max-width:1280px){
    body[data-presence-kind="contest_problem"] .main-area{margin-left:0!important;width:100%!important;min-width:0}
    body[data-presence-kind="contest_problem"] .problem-read-layout{grid-template-columns:minmax(0,1fr)!important;gap:0!important}
    body[data-presence-kind="contest_problem"] .content{padding-left:18px!important;padding-right:18px!important}
    body[data-presence-kind="contest_problem"] .sidebar{
        display:block!important;position:fixed!important;top:0!important;bottom:0!important;left:0!important;
        width:var(--sidebar-width)!important;height:100vh!important;z-index:1200!important;
        transform:translateX(calc(-100% - 12px));transition:transform .18s ease;
        box-shadow:10px 0 28px rgba(15,23,42,.18);overflow:hidden;
    }
    body[data-presence-kind="contest_problem"].problem-left-open .sidebar{transform:translateX(0)}
    body[data-presence-kind="contest_problem"] .compact-submit-side{
        display:block!important;position:fixed!important;top:0!important;right:0!important;bottom:0!important;left:auto!important;
        width:var(--sidebar-width)!important;min-width:var(--sidebar-width)!important;max-width:var(--sidebar-width)!important;
        height:100vh!important;z-index:1200!important;padding:18px 14px;background:#fff;border-left:1px solid var(--border);
        transform:translateX(calc(100% + 12px));transition:transform .18s ease;overflow-y:auto;
        box-shadow:-10px 0 28px rgba(15,23,42,.18);
    }
    body[data-presence-kind="contest_problem"].problem-right-open .compact-submit-side{transform:translateX(0)}
    body[data-presence-kind="contest_problem"] .compact-submit-side .problem-info-card{margin:0!important;padding:16px!important}
    body[data-presence-kind="contest_problem"] .problem-drawer-trigger{
        display:block;position:fixed;top:88px;z-index:1150;border:1px solid var(--border);background:#fff;color:var(--primary-dark);
        padding:10px 12px;border-radius:10px;font-weight:900;box-shadow:0 7px 20px rgba(15,23,42,.15);margin:0;
    }
    body[data-presence-kind="contest_problem"] .problem-drawer-left{left:10px}
    body[data-presence-kind="contest_problem"] .problem-drawer-right{right:10px;background:var(--success);color:#fff;border-color:var(--success)}
    body[data-presence-kind="contest_problem"] .problem-drawer-overlay{
        position:fixed;inset:0;z-index:1180;background:rgba(15,23,42,.28);border:0;padding:0;margin:0;
    }
    body[data-presence-kind="contest_problem"].problem-left-open .problem-drawer-overlay,
    body[data-presence-kind="contest_problem"].problem-right-open .problem-drawer-overlay{display:block}
    body[data-presence-kind="contest_problem"] .contest-sidebar-menu{height:calc(100vh - 105px)!important}
    body[data-presence-kind="contest_problem"] .contest-problem-list{max-height:none!important;min-height:0}
    body[data-presence-kind="contest_problem"] .pdf-frame,
    body[data-presence-kind="contest_problem"] .pdf-frame-large,
    body[data-presence-kind="contest_problem"] .pdf-frame-balanced{width:100%!important;min-width:0!important}
}
@media(max-width:700px){
    body[data-presence-kind="contest_problem"] .problem-drawer-trigger{top:auto;bottom:12px;font-size:13px;padding:9px 10px}
    body[data-presence-kind="contest_problem"] .content{padding:12px!important}
}
.statement-focus-mode .problem-drawer-trigger,.statement-focus-mode .problem-drawer-overlay{display:none!important}

/* V3.10.2 - panel Gửi bài giải đồng nhất LAN/NET */
.problem-info-card{font-family:Arial,"Segoe UI",sans-serif!important;font-size:15px!important;padding:16px!important;border:1px solid var(--border)!important;box-shadow:0 6px 18px rgba(13,110,253,.09)!important}
.big-submit-btn{background:var(--primary)!important;color:#fff!important;font-family:inherit!important;font-size:18px!important;line-height:1.2!important;font-weight:900!important;padding:14px 15px!important;border-radius:11px!important;box-shadow:0 7px 18px rgba(13,110,253,.20)!important}
.big-submit-btn:hover{background:var(--primary-dark)!important;filter:none!important}
.big-submit-btn:disabled{background:#94a3b8!important;box-shadow:none!important}
.compact-info-table{table-layout:fixed!important;font-family:inherit!important;font-size:15px!important;line-height:1.32!important}
.compact-info-table td{padding:10px 8px!important;overflow-wrap:anywhere!important;word-break:break-word!important}
.compact-info-table td:first-child{width:42%!important;color:#475569!important;font-weight:800!important;font-size:15px!important}
.compact-info-table td:last-child{width:58%!important;font-size:15px!important;color:var(--text-main)!important;font-weight:500!important}
.compact-info-table code{font-family:inherit!important;font-size:14px!important;color:var(--text-main)!important;white-space:normal!important}
.submit-panel{border-left-color:var(--primary)!important}
.big-final-submit{background:var(--primary)!important}
.problem-drawer-right{background:var(--primary)!important;border-color:var(--primary)!important}