:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-2: #f0f2f5;
  --text: #16191d;
  --muted: #61697a;
  --line: #dfe3ea;
  --accent: #2f6feb;
  --accent-soft: #e7efff;
  --ok: #1a7f4b;
  --ok-soft: #e2f5ea;
  --bad: #c33227;
  --bad-soft: #fdeceb;
  --warn: #a86a00;
  --code-bg: #1e2430;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(16,24,40,.06), 0 8px 24px rgba(16,24,40,.06);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1216;
    --surface: #161a20;
    --surface-2: #1d222a;
    --text: #e8ebf0;
    --muted: #98a1b3;
    --line: #2a313c;
    --accent: #6d9bff;
    --accent-soft: #1b2740;
    --ok: #56c98c;
    --ok-soft: #14291f;
    --bad: #ff8478;
    --bad-soft: #2c1a19;
    --warn: #e0a642;
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 8px 24px rgba(0,0,0,.3);
  }
}

* { box-sizing: border-box; }
/* атрибут hidden должен побеждать любые display из компонентов */
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}
a { color: var(--accent); }
button {
  font: inherit; cursor: pointer; border: 0; border-radius: 9px;
  background: var(--accent); color: #fff; padding: 10px 16px;
}
button:disabled { opacity: .5; cursor: not-allowed; }
button.ghost { background: transparent; color: var(--text); border: 1px solid var(--line); }
button.ghost:hover { background: var(--surface-2); }

/* ---------- вход ---------- */
.login-screen { min-height: 100dvh; display: grid; place-items: center; padding: 24px; }
.login-card {
  width: min(400px, 100%); background: var(--surface); border: 1px solid var(--line);
  border-radius: 18px; padding: 32px; box-shadow: var(--shadow);
}
.login-card h1 { margin: 0 0 6px; font-size: 26px; line-height: 1.25; }
.login-card h1 span { color: var(--accent); }
.login-sub { margin: 0 0 24px; color: var(--muted); font-size: 14px; }
.login-card label { display: block; margin-bottom: 14px; font-size: 13px; color: var(--muted); }
.login-card input {
  width: 100%; margin-top: 6px; padding: 11px 13px; font: inherit; color: var(--text);
  background: var(--surface-2); border: 1px solid var(--line); border-radius: 9px;
}
.login-card button { width: 100%; margin-top: 8px; padding: 12px; }
.login-error { margin: 14px 0 0; color: var(--bad); font-size: 14px; }
.login-admin { display: block; margin-top: 20px; font-size: 13px; text-align: center; }

/* ---------- каркас ---------- */
.topbar {
  position: sticky; top: 0; z-index: 20; display: flex; align-items: center; gap: 16px;
  padding: 10px 18px; background: var(--surface); border-bottom: 1px solid var(--line);
}
.topbar-title { font-weight: 600; font-size: 15px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.topbar-progress { margin-left: auto; display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--muted); }
.bar { width: 140px; height: 7px; background: var(--surface-2); border-radius: 99px; overflow: hidden; }
.bar i { display: block; height: 100%; width: 0; background: var(--accent); border-radius: 99px; transition: width .3s; }
.topbar-user { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--muted); }
.topbar-user button { padding: 6px 12px; background: transparent; color: var(--muted); border: 1px solid var(--line); }
.burger { display: none; background: transparent; color: var(--text); padding: 6px 10px; }

.layout { display: grid; grid-template-columns: 300px minmax(0, 1fr); align-items: start; }
.sidebar {
  position: sticky; top: 49px; height: calc(100dvh - 49px); overflow-y: auto;
  padding: 16px 12px 60px; border-right: 1px solid var(--line); background: var(--surface);
}
.content { padding: 32px clamp(16px, 4vw, 56px) 96px; max-width: 900px; min-width: 0; }

/* ---------- сайдбар ---------- */
.side-week { margin-bottom: 6px; }
.side-week > summary {
  list-style: none; cursor: pointer; padding: 9px 10px; border-radius: 9px;
  display: flex; align-items: center; gap: 9px; font-size: 13.5px; font-weight: 600;
}
.side-week > summary::-webkit-details-marker { display: none; }
.side-week > summary:hover { background: var(--surface-2); }
.side-week .wnum {
  flex: 0 0 auto; width: 24px; height: 24px; border-radius: 7px; display: grid; place-items: center;
  background: var(--surface-2); color: var(--muted); font-size: 12px;
}
.side-week[data-done="1"] .wnum { background: var(--ok-soft); color: var(--ok); }
.side-week .wtitle { flex: 1; min-width: 0; }
.side-week .wcount { font-size: 11px; color: var(--muted); font-weight: 500; }
.side-lesson, .side-test {
  display: flex; align-items: center; gap: 9px; width: 100%; text-align: left;
  padding: 7px 10px 7px 12px; margin-left: 22px; border-radius: 8px;
  background: transparent; color: var(--text); font-size: 13px; line-height: 1.35;
}
.side-lesson:hover, .side-test:hover { background: var(--surface-2); }
.side-lesson.active, .side-test.active { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.dot { flex: 0 0 auto; width: 8px; height: 8px; border-radius: 50%; border: 1.5px solid var(--line); }
.dot.started { border-color: var(--warn); background: var(--warn); opacity: .55; }
.dot.done { border-color: var(--ok); background: var(--ok); }
.side-test { font-style: italic; color: var(--muted); }

/* ---------- контент урока ---------- */
.crumbs { font-size: 12.5px; color: var(--muted); margin-bottom: 8px; letter-spacing: .02em; }
.content h1 { font-size: clamp(24px, 3.5vw, 33px); line-height: 1.22; margin: 0 0 12px; }
.goal {
  background: var(--accent-soft); border-radius: var(--radius); padding: 14px 16px;
  font-size: 14.5px; margin-bottom: 28px;
}
.goal b { display: block; font-size: 12px; text-transform: uppercase; letter-spacing: .06em; color: var(--accent); margin-bottom: 4px; }

.block { margin-bottom: 26px; }
.block > h2 {
  font-size: 18px; margin: 0 0 10px; display: flex; align-items: center; gap: 9px;
}
.block > h2::before {
  content: attr(data-icon); font-size: 15px; width: 27px; height: 27px; flex: 0 0 auto;
  display: grid; place-items: center; background: var(--surface-2); border-radius: 8px;
}
.block-body { border-left: 2px solid var(--line); padding-left: 18px; margin-left: 13px; }
.block-body > :first-child { margin-top: 0; }
.block-body > :last-child { margin-bottom: 0; }
.block-body p { margin: 0 0 12px; }
.block-body ul, .block-body ol { margin: 0 0 12px; padding-left: 22px; }
.block-body li { margin-bottom: 5px; }
.block-body h3 { font-size: 15px; margin: 20px 0 8px; }
.block[data-kind="practice"] > h2::before { background: var(--ok-soft); }
.block[data-kind="break"] > h2::before { background: var(--bad-soft); }

code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace; font-size: .88em;
  background: var(--surface-2); padding: 2px 5px; border-radius: 5px;
}
pre {
  background: var(--code-bg); color: #e6edf3; padding: 14px 16px; border-radius: 10px;
  overflow-x: auto; font-size: 13px; line-height: 1.55; margin: 0 0 14px;
}
pre code { background: none; padding: 0; color: inherit; font-size: 13px; }

table { border-collapse: collapse; width: 100%; font-size: 14px; margin-bottom: 14px; display: block; overflow-x: auto; }
th, td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; vertical-align: top; }
th { background: var(--surface-2); }

.callout { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; margin-bottom: 14px; }
.callout.warn { border-color: var(--warn); background: color-mix(in srgb, var(--warn) 8%, var(--surface)); }

.cards { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); margin-bottom: 28px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
.card h3 { margin: 0 0 8px; font-size: 14px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
.card ul { margin: 0; padding-left: 18px; font-size: 14px; }
.card li { margin-bottom: 6px; }

.hw { background: var(--surface); border: 1px solid var(--line); border-left: 3px solid var(--accent); border-radius: var(--radius); padding: 18px 20px; margin-bottom: 28px; }
.hw h2 { margin: 0 0 10px; font-size: 17px; }
.check { list-style: none; padding: 0; margin: 12px 0 0; font-size: 14px; }
.check li { padding-left: 26px; position: relative; margin-bottom: 7px; }
.check li::before {
  content: "☐"; position: absolute; left: 0; top: -1px; font-size: 16px; color: var(--muted);
}
.gloss { font-size: 14px; }
.gloss dt { font-weight: 600; margin-top: 10px; }
.gloss dd { margin: 2px 0 0; color: var(--muted); }
.gloss .en { font-weight: 400; color: var(--muted); font-size: 13px; }

/* ---------- задачи ---------- */
.tasks { margin-top: 36px; }
.tasks__title { font-size: 20px; margin: 0 0 4px; display: flex; align-items: baseline; gap: 10px; }
.tasks__count { font-size: 13px; font-weight: 500; color: var(--muted); }
.tasks__sub { margin: 0 0 18px; color: var(--muted); font-size: 13.5px; }

.task {
  background: var(--surface); border: 1px solid var(--line); border-radius: 14px;
  padding: 18px clamp(14px, 2.5vw, 22px); margin-bottom: 16px;
}
.task.is-solved { border-color: var(--ok); }
.task__head { display: flex; align-items: baseline; gap: 12px; }
.task__head h3 { margin: 0 0 10px; font-size: 16px; }
.task__badge { margin-left: auto; font-size: 12px; color: var(--ok); white-space: nowrap; }
.task__statement { font-size: 14.5px; }
.task__statement p { margin: 0 0 10px; }
.task__statement ul, .task__statement ol { margin: 0 0 10px; padding-left: 22px; }
.task__fixture { font-size: 13px; color: var(--muted); margin: 12px 0 6px; }

.task__code {
  display: block; width: 100%; margin: 14px 0 0; padding: 14px 16px;
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
  font-size: 13px; line-height: 1.55; tab-size: 2;
  color: #e6edf3; background: var(--code-bg);
  border: 1px solid var(--line); border-radius: 10px; resize: vertical;
}
.task__code:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.task__actions { display: flex; align-items: center; gap: 10px; margin-top: 12px; flex-wrap: wrap; }
.task__actions button { padding: 8px 16px; font-size: 14px; }
.task__status { font-size: 13.5px; color: var(--muted); }
.task__status.is-pass { color: var(--ok); font-weight: 600; }
.task__status.is-fail { color: var(--bad); font-weight: 600; }
.task__hint {
  margin: 12px 0 0; padding: 10px 12px; font-size: 13.5px;
  background: var(--surface-2); border-radius: 8px; color: var(--muted);
}

.task__results { list-style: none; margin: 14px 0 0; padding: 0; font-size: 13.5px; }
.task__results li { display: flex; gap: 9px; padding: 6px 0; align-items: flex-start; }
.task__results .mark { flex: 0 0 auto; width: 16px; }
.task__results .ok { color: var(--ok); }
.task__results .fail { color: var(--bad); }
.task__results em { display: block; font-style: normal; color: var(--muted); font-size: 12.5px; margin-top: 2px; }
.task__logs { margin-top: 12px; max-height: 200px; overflow: auto; font-size: 12.5px; }

/* ---------- тест ---------- */
.quiz { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 22px clamp(16px, 3vw, 26px); margin-top: 36px; box-shadow: var(--shadow); }
.quiz > h2 { margin: 0 0 4px; font-size: 20px; }
.quiz .quiz-sub { margin: 0 0 20px; color: var(--muted); font-size: 13.5px; }
.qitem { border-top: 1px solid var(--line); padding: 18px 0 4px; }
.qitem:first-of-type { border-top: 0; padding-top: 0; }
.qtext { font-weight: 600; margin: 0 0 12px; }
.qtext .qn { color: var(--muted); font-weight: 500; margin-right: 6px; }
.opt { display: flex; gap: 10px; align-items: flex-start; padding: 9px 12px; border: 1px solid var(--line); border-radius: 9px; margin-bottom: 8px; cursor: pointer; font-size: 14.5px; }
.opt:hover { background: var(--surface-2); }
.opt input { margin-top: 4px; accent-color: var(--accent); }
.opt.chosen { border-color: var(--accent); background: var(--accent-soft); }
.opt.right { border-color: var(--ok); background: var(--ok-soft); }
.opt.wrong { border-color: var(--bad); background: var(--bad-soft); }
.explain { font-size: 13.5px; color: var(--muted); background: var(--surface-2); border-radius: 8px; padding: 10px 12px; margin: 4px 0 8px; }
.quiz-actions { display: flex; align-items: center; gap: 14px; margin-top: 22px; flex-wrap: wrap; }
.result { font-weight: 600; }
.result.pass { color: var(--ok); }
.result.fail { color: var(--bad); }
.history { font-size: 12.5px; color: var(--muted); margin-top: 10px; }

.nav-lessons { display: flex; justify-content: space-between; gap: 12px; margin-top: 40px; flex-wrap: wrap; }

.overview-week { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; margin-bottom: 12px; }
.overview-week h3 { margin: 0 0 4px; font-size: 16px; }
.overview-week p { margin: 0 0 10px; color: var(--muted); font-size: 14px; }
.pill { display: inline-block; font-size: 12px; padding: 2px 9px; border-radius: 99px; background: var(--surface-2); color: var(--muted); margin-right: 6px; }
.pill.ok { background: var(--ok-soft); color: var(--ok); }

/* ---------- админка ---------- */
.admin-wrap { max-width: 1200px; margin: 0 auto; padding: 28px clamp(14px, 3vw, 32px) 80px; }
.admin-wrap h1 { font-size: 24px; margin: 0 0 6px; }
.admin-sub { color: var(--muted); font-size: 14px; margin: 0 0 26px; }
.admin-table { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.admin-table table { display: table; margin: 0; }
.admin-table td, .admin-table th { border: 0; border-bottom: 1px solid var(--line); font-size: 13.5px; }
.minibar { width: 110px; height: 6px; background: var(--surface-2); border-radius: 99px; overflow: hidden; display: inline-block; vertical-align: middle; margin-right: 8px; }
.minibar i { display: block; height: 100%; background: var(--accent); }
.addform { display: flex; gap: 10px; flex-wrap: wrap; margin: 24px 0; }
.addform input { padding: 9px 12px; font: inherit; color: var(--text); background: var(--surface); border: 1px solid var(--line); border-radius: 9px; }
.grid-map { display: grid; grid-template-columns: repeat(48, 1fr); gap: 2px; max-width: 420px; }
.grid-map i { display: block; aspect-ratio: 1; border-radius: 2px; background: var(--surface-2); }
.grid-map i.done { background: var(--ok); }

.admin-head { display: flex; align-items: flex-start; gap: 16px; justify-content: space-between; flex-wrap: wrap; }
.admin-head h2 { margin: 0 0 6px; font-size: 19px; }
.dim { color: var(--muted); }
.err { color: var(--bad); font-size: 13px; align-self: center; }
button.tiny { padding: 5px 10px; font-size: 12px; }
button.link {
  background: none; color: var(--accent); padding: 0; font-weight: 600;
  text-align: left; text-decoration: underline; text-underline-offset: 2px;
}

.addbox {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 14px 18px; margin: 22px 0;
}
.addbox > summary { cursor: pointer; font-weight: 600; }
.addbox p { font-size: 13.5px; margin: 14px 0 8px; }
.addbox textarea {
  width: 100%; padding: 10px 12px; font: inherit; font-size: 14px;
  color: var(--text); background: var(--surface-2);
  border: 1px solid var(--line); border-radius: 9px; resize: vertical;
}
.addform-actions { display: flex; gap: 12px; align-items: center; margin-top: 10px; flex-wrap: wrap; }

.creds {
  background: var(--surface); border: 1px solid var(--ok); border-radius: var(--radius);
  padding: 16px 18px; margin-bottom: 22px;
}
.creds h3 { margin: 0 0 6px; font-size: 16px; }
.creds p { font-size: 13.5px; margin: 0 0 12px; }
.creds-table { width: 100%; font-size: 13.5px; margin-bottom: 12px; }
.creds-table code { font-size: 13px; }
.creds textarea {
  width: 100%; margin-top: 12px; padding: 10px 12px;
  font-family: ui-monospace, Menlo, monospace; font-size: 12.5px;
  color: var(--text); background: var(--surface-2);
  border: 1px solid var(--line); border-radius: 9px;
}

.detail {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px 20px; margin-top: 26px;
}
.detail-week { border-top: 1px solid var(--line); padding: 10px 0; }
.detail-week > summary { cursor: pointer; font-size: 14px; font-weight: 600; padding: 4px 0; }
.detail-table { font-size: 13px; margin: 10px 0 0; }
.detail-table th, .detail-table td { padding: 5px 8px; }
.detail-table .row-done td:first-child { color: var(--ok); }

@media (max-width: 900px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .burger { display: block; }
  .sidebar {
    position: fixed; inset: 49px auto 0 0; width: 290px; z-index: 30;
    transform: translateX(-100%); transition: transform .22s; box-shadow: var(--shadow);
  }
  body.nav-open .sidebar { transform: none; }
  .topbar-title { display: none; }
  .topbar-progress .bar { width: 80px; }
  .content { padding: 22px 16px 80px; }
}