*, *::before, *::after { box-sizing: border-box; }

html, body { height: 100%; margin: 0; }

body {
    display: flex;
    flex-direction: column;
    background: var(--c-bg);
    color: var(--c-text);
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    line-height: 1.5;
}

:root {
    --c-bg: #f8fafc;
    --c-surface: #ffffff;
    --c-text: #0f172a;
    --c-text-muted: #64748b;
    --c-text-link: #6366f1;
    --c-text-link-hover: #4f46e5;
    --c-border: #e2e8f0;
    --c-accent: #6366f1;
    --c-badge-ok-bg: #dcfce7;
    --c-badge-ok-text: #166534;
    --c-badge-warn-bg: #fef3c7;
    --c-badge-warn-text: #92400e;
}

[data-theme="dark"] {
    --c-bg: #0f1115;
    --c-surface: #171a21;
    --c-text: #e7e9ee;
    --c-text-muted: #9aa3b2;
    --c-text-link: #6ea8fe;
    --c-text-link-hover: #8bb9fe;
    --c-border: #262b36;
    --c-accent: #6ea8fe;
    --c-badge-ok-bg: rgba(16, 185, 129, 0.15);
    --c-badge-ok-text: #6ee7b7;
    --c-badge-warn-bg: rgba(251, 191, 36, 0.15);
    --c-badge-warn-text: #fcd34d;
}

a { color: var(--c-text-link); }
a:hover { color: var(--c-text-link-hover); }

/* Layout */
.page { display: flex; flex-direction: column; min-height: 100vh; }
.page-header { position: sticky; top: 0; z-index: 10; border-bottom: 1px solid var(--c-border); background: var(--c-surface); }
.page-header-inner { max-width: 1152px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 0.5rem 1rem; flex-wrap: wrap; padding: 0.75rem 1.5rem; }
@media (max-width: 640px) {
    .page-header-inner { padding: 0.5rem 0.75rem; }
    .nav { width: 100%; gap: 0.5rem 0.75rem; flex-wrap: wrap; font-size: 0.8125rem; }
    .nav .btn { padding: 0.25rem 0.6rem; font-size: 0.75rem; }
    .nav-user { max-width: 100%; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
}
.page-main { flex: 1; width: 100%; max-width: 1152px; margin: 0 auto; padding: 2rem 1.5rem; }
.page-footer { border-top: 1px solid var(--c-border); padding: 1rem; text-align: center; font-size: 0.75rem; color: var(--c-text-muted); }

/* Nav */
.nav { display: flex; align-items: center; gap: 1rem; font-size: 0.875rem; }
.nav-link { color: var(--c-text-link); text-decoration: none; }
.nav-link:hover { color: var(--c-text-link-hover); }
.nav-sep { color: var(--c-text-muted); }
.logo { font-size: 1.125rem; font-weight: 600; color: var(--c-text); text-decoration: none; }
.nav-user { font-weight: 500; }
.theme-btn { display: inline-flex; align-items: center; justify-content: center; padding: 0.3rem 0.5rem; }
.theme-icon { width: 1.05rem; height: 1.05rem; display: block; }
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 0.35rem; }
.breadcrumb .nav-sep { user-select: none; }
.check-list { display: flex; flex-direction: column; gap: 0.25rem; margin-top: 0.25rem; max-height: 12rem; overflow-y: auto; }

/* Buttons */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
    border-radius: 0.5rem; padding: 0.5rem 1rem; font-size: 0.875rem; font-weight: 500;
    border: none; cursor: pointer; transition: opacity 0.15s;
}
.btn:active { opacity: 0.8; }
.btn-sm { padding: 0.25rem 0.5rem; font-size: 0.75rem; }
.btn-primary { background: var(--c-accent); color: white; text-decoration: none; }
.btn-primary:hover { opacity: 0.9; }
.btn-secondary {
    background: var(--c-surface); color: var(--c-text); text-decoration: none;
    box-shadow: inset 0 0 0 1px var(--c-border);
}
.btn-secondary:hover { background: var(--c-border); }

/* Forms */
.input {
    width: 100%; border-radius: 0.5rem; background: var(--c-bg); color: var(--c-text);
    padding: 0.5rem 0.75rem; font-size: 0.875rem; border: 1px solid var(--c-border);
    outline: none;
}
.input:focus { border-color: var(--c-accent); box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2); }
.input::placeholder { color: var(--c-text-muted); }
.label { display: block; margin-bottom: 0.25rem; font-size: 0.875rem; font-weight: 500; }
.hint { margin-top: 0.25rem; font-size: 0.75rem; color: var(--c-text-muted); }

/* Cards */
.card { border-radius: 0.75rem; background: var(--c-surface); border: 1px solid var(--c-border); }
.card-flush { border-radius: 0.75rem; background: var(--c-surface); border: 1px solid var(--c-border); padding: 0; }
.card-body { padding: 1.5rem; }

/* Grid */
.grid { display: grid; gap: 1rem; }
.grid-2 { grid-template-columns: repeat(auto-fill, minmax(22rem, 1fr)); }
.grid-stats { grid-template-columns: repeat(auto-fill, minmax(12rem, 1fr)); }

/* Typography */
.page-title { margin: 0 0 1.5rem; font-size: 1.5rem; font-weight: 600; }
.section-title { margin: 0 0 0.75rem; font-size: 1.125rem; font-weight: 500; }
.stat-value { margin: 0.5rem 0 0; font-size: 1.875rem; font-weight: 600; }
.stat-title { font-size: 0.875rem; color: var(--c-text-muted); margin: 0; }
.text-muted { color: var(--c-text-muted); }
.opacity-30 { opacity: 0.3; }
.text-center { text-align: center; }
.text-sm { font-size: 0.875rem; }
.font-mono { font-family: monospace; }

/* Spacing */
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-4 { margin-top: 1rem; }
.mt-6 { margin-top: 1.5rem; }
.mt-8 { margin-top: 2rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }
.ml-2 { margin-left: 0.5rem; }
.p-0 { padding: 0; }
.p-4 { padding: 1rem; }
.p-6 { padding: 1.5rem; }
.px-6 { padding-left: 1.5rem; padding-right: 1.5rem; }
.py-3 { padding-top: 0.75rem; padding-bottom: 0.75rem; }
.gap-2 { gap: 0.5rem; }
.gap-4 { gap: 1rem; }

/* Flex */
.flex { display: flex; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.w-full { width: 100%; }
.overflow-x-auto { overflow-x: auto; }

/* Badges */
.badge { display: inline-flex; align-items: center; border-radius: 9999px; padding: 0.125rem 0.625rem; font-size: 0.75rem; font-weight: 500; }
.badge-ok { background: var(--c-badge-ok-bg); color: var(--c-badge-ok-text); }
.badge-warn { background: var(--c-badge-warn-bg); color: var(--c-badge-warn-text); }
.badge-btn { border: none; cursor: pointer; padding: 0.125rem 0.625rem; }

/* Tables */
table { width: 100%; font-size: 0.875rem; border-collapse: collapse; }
th { text-align: left; font-weight: 500; color: var(--c-text-muted); padding: 0.75rem 1.5rem; border-bottom: 1px solid var(--c-border); }
td { padding: 0.75rem 1.5rem; border-bottom: 1px solid var(--c-border); }
tr:last-child td { border-bottom: none; }

/* Alerts */
.alert { padding: 0.75rem 1rem; border-radius: 0.5rem; font-size: 0.875rem; margin-bottom: 1rem; }
.alert-error { background: #fef2f2; color: #991b1b; }
.alert-success { background: #dcfce7; color: #166534; }
.alert-warning { background: #fef3c7; color: #92400e; }

.ml-2 { margin-left: 0.5rem; }
.list-pad { padding-left: 1.25rem; }
.import-card { border-color: rgba(16,185,129,0.4); }
.mini-alert { padding: 0.5rem 0.75rem; border-radius: 0.25rem; margin-bottom: 0.5rem; }
.font-semibold { font-weight: 600; }

/* Theme toggle */
.theme-btn { padding: 0.25rem 0.5rem; font-size: 0.75rem; }

/* Group assignment page */
.group-title { margin: 0 0 0.5rem; font-size: 1rem; font-weight: 600; }
.inline-form { display: inline-flex; align-items: center; gap: 0.375rem; margin: 0; }
.inline-form .input-sm { width: auto; min-width: 10rem; }
.input-sm { padding: 0.25rem 0.5rem; font-size: 0.8125rem; }
.input-score { width: 4.5rem; }
.inline-form .input-sm { width: auto; min-width: 0; }
.inline-form .input-score, input[type="number"].input-score { width: 4.5rem; min-width: 4.5rem; flex: 0 0 auto; }
.filter-select { width: auto; }
.hidden { display: none !important; }

/* Toast-уведомление */
.toast { position: fixed; top: 1rem; right: 1rem; z-index: 50; width: 20rem; }

/* Modals */
dialog.modal {
    border: none; border-radius: 0.75rem; padding: 0;
    background: var(--c-surface); color: var(--c-text);
    width: min(34rem, calc(100vw - 2rem));
    box-shadow: 0 20px 60px rgba(0,0,0,0.35);
}
dialog.modal::backdrop { background: rgba(0,0,0,0.55); }
.modal-header { display: flex; align-items: center; justify-content: space-between; padding: 1rem 1.5rem; border-bottom: 1px solid var(--c-border); }
.modal-title { margin: 0; font-size: 1.0625rem; font-weight: 600; }
.modal-close { border: none; background: none; cursor: pointer; font-size: 1.25rem; color: var(--c-text-muted); padding: 0 0.25rem; }
.modal-close:hover { color: var(--c-text); }
.modal-body { padding: 1.5rem; max-height: 70vh; overflow-y: auto; }

/* Двухуровневые формы уровней лабы */
.level-row { display: flex; gap: 0.5rem; align-items: center; margin-bottom: 0.5rem; }
.level-row .input { flex: 1; }

/* Markdown body */
.md-body { font-size: 0.9375rem; }
.md-body h1, .md-body h2, .md-body h3 { margin: 1rem 0 0.5rem; line-height: 1.3; }
.md-body h1 { font-size: 1.25rem; }
.md-body h2 { font-size: 1.125rem; }
.md-body p, .md-body ul, .md-body ol { margin: 0.5rem 0; }
.md-body ul, .md-body ol { padding-left: 1.5rem; }
.md-body pre { background: var(--c-bg); border: 1px solid var(--c-border); border-radius: 0.5rem; padding: 0.75rem 1rem; overflow-x: auto; font-size: 0.8125rem; }
.md-body code { font-family: monospace; }
.md-body details.spoiler { border: 1px solid var(--c-border); border-radius: 0.5rem; padding: 0.5rem 0.75rem; margin: 0.5rem 0; }
.md-body details.spoiler summary { cursor: pointer; font-weight: 500; color: var(--c-text-link); }
.md-body img { max-width: 100%; }
.md-body table { margin: 0.5rem 0; }

/* Empty state */
.empty { text-align: center; color: var(--c-text-muted); padding: 1.5rem; }

/* Mono inline code */
code.code { padding: 0.125rem 0.5rem; border-radius: 0.25rem; font-family: monospace; background: var(--c-bg); }

/* Containers */
.container-sm { max-width: 28rem; margin: 0 auto; }
.form-stack { display: flex; flex-direction: column; gap: 1rem; }
.form-card { padding: 1.5rem; }

/* Header logo */
.link-inherit { font-size: 0.875rem; }/* Chips (оценочные комментарии) */
.chip { display: inline-block; margin: 2px 4px 2px 0; padding: 2px 8px; border-radius: 9999px; font-size: 11.5px; line-height: 1.5; }
.chip-pos { background: #16803c; color: #fff; }
.chip-neu { background: #5d6570; color: #fff; }
.chip-neg { background: #b3283b; color: #fff; }
/* Слоты комментариев в диалоге */
.cs-row { display: flex; gap: 6px; align-items: center; }

.chip { display: inline-block; margin: 2px 4px 2px 0; padding: 2px 8px; border-radius: 9999px; font-size: 11.5px; line-height: 1.5; }
.chip-pos { background: #16803c; color: #fff; }
.chip-neu { background: #5d6570; color: #fff; }
.chip-neg { background: #b3283b; color: #fff; }

/* Defense timer */
/* Accordion (главы/разделы в /learn) */
details.accordion > summary.acc-head { list-style: none; cursor: pointer; display: flex; align-items: center; justify-content: space-between; }
details.accordion > summary::-webkit-details-marker { display: none; }
details.accordion[open] > .acc-head, details.accordion > summary { margin-bottom: 0; }
.acc-arrow { width: 10px; height: 10px; border-right: 2px solid var(--c-text-muted); border-bottom: 2px solid var(--c-text-muted); transform: rotate(45deg); transition: transform 0.2s; margin-left: .75rem;}
details.accordion[open] > summary > .acc-arrow { transform: rotate(-135deg); }
.acc-title { margin: 0; font-size: 1.0625rem; }
.acc-body { border-top: 1px solid var(--c-border); }
details.sub-acc > summary.sub-head { list-style: none; cursor: pointer; }
details.sub-acc > summary::-webkit-details-marker { display: none; }
.sub-arrow { display: inline-block; width: 8px; height: 8px; border-right: 2px solid var(--c-text-muted); border-bottom: 2px solid var(--c-text-muted); transform: rotate(45deg); transition: transform 0.2s; margin-right: 6px; vertical-align: 2px;}
details.sub-acc[open] > summary .sub-arrow { transform: rotate(-135deg); }
.sub-actions { margin: 0 0 2px 18px; }

/* ---- Матрица группы и карточки защиты ---- */
.m-0 { margin: 0; }
.mb-8 { margin-bottom: 2rem; }
.mb-0 { margin-bottom: 0; }
.text-strong { font-weight: 600; color: var(--c-text); }
.text-right { text-align: right; }
.font-medium { font-weight: 500; }
.scroll-x { overflow-x: auto; }
.matrix { border-collapse: separate; border-spacing: 0; }
.matrix th, .matrix td { vertical-align: top; }
.matrix th.lab-col { min-width: 9.5rem; border-left: 1px solid var(--c-border); }
.matrix td.cell-lab { min-width: 9.5rem; border-left: 1px solid var(--c-border); }
.matrix td.student-cell { min-width: 12rem; }
.lab-col-head { display: flex; flex-direction: column; align-items: center; gap: 0.375rem; }
.cell-line { display: flex; align-items: center; gap: 0.375rem; font-size: 0.8125rem; text-align: left; }
.cell-label { color: var(--c-text-muted); min-width: 3.5rem; }
.cell-link { font-size: 0.8125rem; }
.cell-edit { padding: 0 0.4rem; }
.cell-grade-line { font-weight: 500; }
.defense-cell-actions { display: flex; gap: 0.35rem; justify-content: flex-end; flex-wrap: wrap; }
.th-w-sm { width: 4rem; }
.th-w-md { width: 12rem; }
.span-2 { grid-column: 1 / -1; }
.preview { max-width: 34rem; }
.md-preview { max-width: 22rem; }

/* ---- Комментарии к оценке (ЛК студента) ---- */
.review-cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); gap: 1rem; }
.review-col h3 { margin-bottom: 0.35rem; }
.review-list { margin: 0; padding-left: 1.15rem; }
.review-list li { margin: 0.15rem 0; }
.tone-positive-text { color: #166534; }
.tone-negative-text { color: #991b1b; }
[data-theme="dark"] .tone-positive-text { color: #6ee7b7; }
[data-theme="dark"] .tone-negative-text { color: #fca5a5; }
.tone-label { display: flex; align-items: center; gap: 0.5rem; font-size: 0.875rem; }
.pre-wrap { white-space: pre-wrap; word-break: break-word; }

/* Редактируемая матрица: закреплённый столбец и компактные селекты */
.matrix-sticky { position: sticky; left: 0; z-index: 2; background: var(--c-surface); }
.matrix thead .matrix-sticky { z-index: 3; }
.level-form { margin: 0; }
.level-select {
    width: auto; min-width: 6rem; max-width: 9.5rem;
    padding: 0.15rem 1.5rem 0.15rem 0.4rem; font-size: 0.75rem;
}
.cell-level { justify-content: center; }
.pin-hint { font-size: 0.75rem; }

/* Компактные ячейки матрицы группы */
.btn-xs { padding: 0.05rem 0.4rem; font-size: 0.7rem; line-height: 1.5; }
.badge-xs { font-size: 0.65rem; padding: 0.05rem 0.4rem; }
.chip-xs { font-size: 0.65rem; padding: 0.05rem 0.4rem; }
.cell-top { display: flex; align-items: center; justify-content: center; gap: 0.25rem; }
.cell-chips { display: flex; flex-wrap: wrap; gap: 0.18rem; justify-content: center; margin-top: 0.25rem; }
.cell-chip {
    display: inline-flex; align-items: center; gap: 0.15rem;
    font-size: 0.72rem; line-height: 1.7; padding: 0.05rem 0.45rem;
    border: 1px solid var(--c-border); border-radius: 99px;
    background: var(--c-bg); color: var(--c-text); white-space: nowrap; cursor: pointer;
    text-decoration: none; font-family: inherit;
}
.cell-chip:hover { border-color: var(--c-border-strong, var(--c-border)); filter: brightness(0.97); }
.chip-dim { color: var(--c-text-muted); }
.chip-warn { color: #92400e; background: #fef3c7; border-color: #fde68a; }
.chip-ok { color: #166534; background: #dcfce7; border-color: #bbf7d0; }
.chip-link:hover { color: var(--c-text-link); }
[data-theme="dark"] .chip-warn { color: #fcd34d; background: rgba(146, 64, 14, 0.25); border-color: rgba(146, 64, 14, 0.5); }
[data-theme="dark"] .chip-ok { color: #86efac; background: rgba(22, 101, 52, 0.25); border-color: rgba(22, 101, 52, 0.5); }
.lab-head-row { display: flex; align-items: center; justify-content: center; gap: 0.3rem; }
.actions-cell { white-space: nowrap; }
.actions-cell .inline-form { display: inline-block; }

/* tablekit: сортируемые таблицы и поиск */
th.th-sortable { cursor: pointer; user-select: none; }
th.th-sortable:hover { background: var(--c-surface); }
th.th-sortable.is-asc::after { content: " ▲"; color: var(--c-text-muted); font-size: 0.7rem; }
th.th-sortable.is-desc::after { content: " ▼"; color: var(--c-text-muted); font-size: 0.7rem; }
.row-hidden { display: none !important; }
.table-search { width: 14rem; }
@media (max-width: 640px) { .table-search { width: 100%; } }
.filter-row th { padding: 0.25rem 0.35rem; background: var(--c-bg); }
.filter-control {
    width: 100%; min-width: 3.5rem; font-size: 0.72rem; line-height: 1.4;
    padding: 0.1rem 0.25rem; border: 1px solid var(--c-border); border-radius: 0.35rem;
    background: var(--c-surface); color: var(--c-text); font-family: inherit;
}
th.th-filterable { padding-bottom: 0.35rem; }