:root {
  --bg: #0e1116;
  --bg-2: #151a21;
  --bg-3: #1c232c;
  --line: #262f3a;
  --fg: #e6edf3;
  --fg-2: #9fb0c0;
  --muted: #6f8296;
  --accent: #4c9aff;
  --ok: #3fb950;
  --warn: #d29922;
  --fail: #f85149;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --radius: 10px;
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f7f9fb;
  --bg-2: #ffffff;
  --bg-3: #eef2f6;
  --line: #dde3ea;
  --fg: #16202b;
  --fg-2: #3d4c5c;
  --muted: #6b7b8c;
  --accent: #1f6feb;
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.6 var(--sans);
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
code { font-family: var(--mono); font-size: 0.9em; background: var(--bg-3); padding: 1px 5px; border-radius: 4px; }

/* ---- layout ---- */
.topbar {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; gap: 24px;
  padding: 0 20px; height: 56px;
  background: var(--bg-2); border-bottom: 1px solid var(--line);
}
.brand { color: var(--fg); font-size: 15px; letter-spacing: .2px; }
.brand b { color: var(--accent); }
.topnav { display: flex; gap: 18px; margin-left: auto; }
.topnav a { color: var(--fg-2); font-size: 14px; }
.topnav a:hover { color: var(--fg); text-decoration: none; }
.topright { display: flex; align-items: center; gap: 14px; }
.total { color: var(--fg-2); font-size: 13px; }
.total b { color: var(--fg); }

.shell { display: grid; grid-template-columns: 280px minmax(0, 1fr); align-items: start; }
.sidebar {
  position: sticky; top: 56px; height: calc(100vh - 56px); overflow-y: auto;
  border-right: 1px solid var(--line); padding: 16px 10px; background: var(--bg-2);
}
.side-title { font-size: 11px; text-transform: uppercase; letter-spacing: .8px; color: var(--muted); padding: 0 10px 8px; }
.nav-item {
  display: grid; grid-template-columns: 34px 1fr auto; gap: 8px; align-items: center;
  padding: 7px 10px; border-radius: 8px; color: var(--fg-2); font-size: 13.5px;
}
.nav-item:hover { background: var(--bg-3); color: var(--fg); text-decoration: none; }
.nav-item.active { background: var(--bg-3); color: var(--fg); box-shadow: inset 2px 0 0 var(--accent); }
.nav-item.empty { opacity: .5; }
.nav-code { font-family: var(--mono); font-size: 11px; color: var(--muted); }
.nav-title { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.nav-pct { font-size: 11px; color: var(--muted); font-variant-numeric: tabular-nums; }

.content { padding: 28px 36px 80px; max-width: 940px; }

h1 { font-size: 27px; line-height: 1.25; margin: 0 0 10px; letter-spacing: -.2px; }
h2 { font-size: 20px; margin: 28px 0 10px; }
h3 { font-size: 16px; margin: 22px 0 8px; }
.sec-title { border-top: 1px solid var(--line); padding-top: 20px; }
.lead { color: var(--fg-2); font-size: 15.5px; max-width: 70ch; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.ok { color: var(--ok); }
.fail { color: var(--fail); }

/* ---- crumbs / badges ---- */
.crumbs { display: flex; gap: 8px; align-items: center; font-size: 12.5px; color: var(--muted); margin-bottom: 14px; }
.crumbs i { font-style: normal; opacity: .5; }
.badge { font-size: 11px; padding: 2px 8px; border-radius: 20px; border: 1px solid var(--line); color: var(--fg-2); vertical-align: middle; }
.badge.b-s { border-color: #7a4dff55; background: #7a4dff1a; color: #b39bff; }
.badge.b-m { border-color: #3fb95055; background: #3fb9501a; color: #7ee08a; }

/* ---- cards ---- */
.card { background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; margin: 16px 0; }
.card-title { font-size: 14px; margin: 0 0 10px; text-transform: uppercase; letter-spacing: .6px; color: var(--muted); }
.card.good { border-left: 3px solid var(--ok); }
.card.bad { border-left: 3px solid var(--fail); }
.card.check { border-left: 3px solid var(--accent); }
.card.src { border-left: 3px solid var(--muted); }
.card.asked-card { border-left: 3px solid var(--warn); }
.asked { margin: 0; padding-left: 20px; }
.asked li { margin: 6px 0; color: var(--fg); }

.mod-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 14px; }
.mod-card { display: block; background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; color: var(--fg); }
.mod-card:hover { border-color: var(--accent); text-decoration: none; }
.mod-card.pending { opacity: .6; }
.mod-card h3 { margin: 4px 0 6px; font-size: 15.5px; }
.mod-card p { margin: 0 0 12px; color: var(--fg-2); font-size: 13px; }
.mod-head { display: flex; justify-content: space-between; align-items: center; }
.mod-code { font-family: var(--mono); font-size: 11px; color: var(--muted); }
.mod-prio { font-size: 10px; padding: 1px 6px; border-radius: 4px; border: 1px solid var(--line); color: var(--muted); }
.mod-prio.pP0 { color: var(--fail); border-color: #f8514955; }
.mod-prio.pP1 { color: var(--warn); border-color: #d2992255; }
.mod-meta { font-size: 12px; color: var(--muted); margin-top: 8px; }

.pbar { height: 6px; background: var(--bg-3); border-radius: 6px; overflow: hidden; }
.pbar span { display: block; height: 100%; background: linear-gradient(90deg, var(--accent), #7a4dff); }
.stat-row { display: flex; gap: 28px; margin: 14px 0 4px; flex-wrap: wrap; }
.stat b { display: block; font-size: 22px; line-height: 1.2; }
.stat span { font-size: 12px; color: var(--muted); }

/* ---- lists ---- */
.topic-list { list-style: none; padding: 0; margin: 8px 0; counter-reset: t; }
.topic-list li a, .task-list li a {
  display: flex; align-items: center; gap: 10px; padding: 9px 12px;
  border: 1px solid var(--line); border-radius: 8px; margin-bottom: 6px;
  background: var(--bg-2); color: var(--fg);
}
.topic-list li a:hover, .task-list li a:hover { border-color: var(--accent); text-decoration: none; }
.task-list { list-style: none; padding: 0; margin: 8px 0; }
.tt { flex: 1; }
.tstatus { width: 16px; text-align: center; color: var(--muted); }
.tstatus.known, .tstatus.solved { color: var(--ok); }
.tstatus.learning { color: var(--warn); }
.kind { font-size: 10.5px; font-family: var(--mono); padding: 2px 7px; border-radius: 4px; background: var(--bg-3); color: var(--fg-2); min-width: 78px; text-align: center; }
.kind.k-sql { color: #7ee08a; }
.kind.k-security { color: #ff8a8a; }
.kind.k-case { color: #ffd479; }
.snippet { font-size: 12px; padding: 0 12px 8px; }

/* ---- prose ---- */
.prose { max-width: 74ch; }
.prose h2 { font-size: 18px; }
.prose h3 { font-size: 15px; }
.prose ul, .prose ol { padding-left: 22px; }
.prose li { margin: 5px 0; }
.prose blockquote { margin: 12px 0; padding: 8px 14px; border-left: 3px solid var(--accent); background: var(--bg-3); border-radius: 0 6px 6px 0; color: var(--fg-2); }
.prose p { margin: 10px 0; }

pre.code {
  background: var(--bg-3); border: 1px solid var(--line); border-radius: 8px;
  padding: 12px 14px; overflow-x: auto; font-family: var(--mono); font-size: 12.5px; line-height: 1.5;
}
pre.code code { background: none; padding: 0; }

.tw { overflow-x: auto; margin: 12px 0; }
table { border-collapse: collapse; width: 100%; font-size: 13.5px; }
th, td { text-align: left; padding: 7px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-weight: 600; font-size: 12px; text-transform: uppercase; letter-spacing: .4px; }
td.en { font-family: var(--mono); font-size: 12.5px; color: var(--fg-2); }

/* ---- controls ---- */
.btn {
  display: inline-block; padding: 7px 14px; border-radius: 7px; border: 1px solid transparent;
  background: var(--accent); color: #fff; font: inherit; font-size: 13.5px; cursor: pointer;
}
.btn:hover { filter: brightness(1.1); text-decoration: none; }
.btn:disabled { opacity: .5; cursor: default; }
.btn.ghost { background: transparent; border-color: var(--line); color: var(--fg-2); }
.btn.ghost:hover { color: var(--fg); border-color: var(--accent); }
.btn.danger.ghost { color: var(--fail); border-color: #f8514955; }
.row-actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-top: 12px; }
.form-row { display: flex; gap: 10px; align-items: center; margin: 10px 0; }
.form-row label { min-width: 130px; color: var(--fg-2); font-size: 13.5px; }
select, input[type="text"], input:not([type]) {
  background: var(--bg-3); color: var(--fg); border: 1px solid var(--line);
  border-radius: 7px; padding: 7px 10px; font: inherit; font-size: 14px; min-width: 220px;
}
textarea {
  width: 100%; min-height: 150px; background: var(--bg-3); color: var(--fg);
  border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px;
  font-family: var(--mono); font-size: 13px; line-height: 1.55; resize: vertical;
}
textarea:focus, select:focus, input:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
.editor { margin: 16px 0; }

.collapse { margin: 12px 0; }
.collapse-head {
  width: 100%; text-align: left; background: var(--bg-2); color: var(--fg-2);
  border: 1px solid var(--line); border-radius: 8px; padding: 9px 14px; font: inherit; font-size: 13.5px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
}
.collapse-head:hover { color: var(--fg); border-color: var(--accent); }
.collapse-head i { font-style: normal; transition: transform .15s; }
.collapse-head.open i { transform: rotate(180deg); }
.collapse-body { padding: 12px 2px; }

.verdict { padding: 11px 14px; border-radius: 8px; margin: 14px 0; font-size: 14px; }
.verdict.ok { background: #3fb9501a; border: 1px solid #3fb95055; }
.verdict.fail { background: #f851491a; border: 1px solid #f8514955; }
.verdict.warn { background: #d299221a; border: 1px solid #d2992255; }
.criteria { list-style: none; padding: 0; }
.criteria li { margin: 7px 0; }
.criteria input { margin-right: 8px; }
.score { font-size: 13.5px; color: var(--fg-2); }

.topic-foot { margin-top: 34px; border-top: 1px solid var(--line); padding-top: 18px; }
.mark { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; font-size: 13.5px; color: var(--fg-2); }
.mark .cur { margin-left: auto; }
.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 18px; }

.iv-head { display: flex; gap: 16px; align-items: center; color: var(--fg-2); font-size: 13px; margin-bottom: 8px; }
.iv-q { font-size: 22px; max-width: 70ch; }
.clock { margin-left: auto; font-family: var(--mono); font-size: 15px; color: var(--fg-2); }
.clock.warn { color: var(--fail); }

@media (max-width: 900px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { position: static; height: auto; border-right: none; border-bottom: 1px solid var(--line); }
  .content { padding: 20px 16px 60px; }
  .topnav { gap: 12px; font-size: 13px; }
}

/* ---- iPad / touch ---- */
html { -webkit-text-size-adjust: 100%; }
@media (pointer: coarse) {
  textarea, select, input[type="text"], input:not([type]) { font-size: 16px; }
  .btn { padding: 10px 16px; font-size: 15px; }
  .nav-item { padding: 11px 10px; font-size: 15px; }
  .task-list a, .asked li { padding-top: 11px; padding-bottom: 11px; }
  .topnav a { font-size: 15px; }
  input[type="checkbox"] { width: 20px; height: 20px; }
  .criteria label { display: inline-flex; align-items: center; gap: 8px; }
}
@media (max-width: 900px) {
  .topbar { flex-wrap: wrap; height: auto; gap: 10px; padding: 8px 14px; }
  .topnav { margin-left: 0; flex-wrap: wrap; }
  h1 { font-size: 23px; }
  .iv-q { font-size: 20px; }
  .content { padding-left: max(16px, env(safe-area-inset-left)); padding-right: max(16px, env(safe-area-inset-right)); }
}