:root {
  --paper: #f7f3ea;
  --paper-2: #fffdf8;
  --ink: #1f2a24;
  --muted: #6d766f;
  --line: #e2dccf;
  --green: #1f6f4a;
  --green-2: #2f8f62;
  --amber: #c47a1b;
  --red: #b3402f;
  --blue: #2b5f8a;
  --shadow: 0 10px 30px rgba(31, 42, 36, .07);
  --radius: 16px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(1200px 600px at 10% -10%, #efe8d8 0%, transparent 60%),
    radial-gradient(900px 500px at 100% 0%, #e8f1ea 0%, transparent 55%),
    var(--paper);
  color: var(--ink);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--green); text-decoration: none; }
a:hover { text-decoration: underline; }
code, pre, .editor, .mono { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(12px);
  background: rgba(247, 243, 234, .82);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 10px 20px;
  display: flex;
  align-items: center;
  gap: 18px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 800; letter-spacing: .2px; }
.brand:hover { text-decoration: none; }
.brand-mark {
  width: 34px; height: 34px; border-radius: 11px;
  display: grid; place-items: center;
  background: linear-gradient(145deg, var(--green), var(--green-2));
  color: #fff; font-weight: 900;
  box-shadow: 0 6px 14px rgba(31, 111, 74, .25);
}
.brand-sub { display: block; font-size: 11px; font-weight: 500; color: var(--muted); letter-spacing: 1px; }
.nav-links { display: flex; gap: 4px; margin-left: 10px; flex-wrap: wrap; }
.nav-links a {
  color: var(--muted);
  padding: 7px 11px;
  border-radius: 9px;
  font-size: 14px;
  font-weight: 600;
}
.nav-links a:hover { background: #fff; color: var(--ink); text-decoration: none; }
.nav-links a.on { background: #fff; color: var(--green); box-shadow: inset 0 0 0 1px var(--line); }
.nav-user { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.pill { font-size: 12px; color: var(--muted); background: #fff; border: 1px solid var(--line); padding: 4px 9px; border-radius: 999px; }

.wrap { max-width: 1120px; margin: 0 auto; padding: 28px 20px 64px; }

.hero {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin: 8px 0 24px;
}
.eyebrow { margin: 0 0 6px; color: var(--green); font-size: 12px; font-weight: 800; letter-spacing: 1.4px; text-transform: uppercase; }
h1 { margin: 0 0 10px; font-size: clamp(28px, 4vw, 44px); line-height: 1.15; letter-spacing: -.8px; }
.lede { margin: 0; color: var(--muted); max-width: 62ch; }
.hero-stats { display: flex; gap: 10px; }
.stat {
  min-width: 92px; padding: 12px 14px; background: var(--paper-2);
  border: 1px solid var(--line); border-radius: 14px; text-align: center;
  box-shadow: var(--shadow);
}
.stat b { display: block; font-size: 22px; line-height: 1.1; }
.stat span { font-size: 12px; color: var(--muted); }

.grid { display: grid; gap: 18px; }
.grid.two { grid-template-columns: 1.25fr .75fr; margin-bottom: 18px; }
.card {
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}
.card-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 12px; }
.card-head h2 { margin: 0; font-size: 17px; letter-spacing: -.2px; }
.muted { color: var(--muted); }
.small { font-size: 12.5px; }

.task-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.task {
  display: flex; align-items: center; gap: 12px;
  padding: 12px; border: 1px solid var(--line); border-radius: 12px;
  background: #fff;
}
.task-num {
  width: 28px; height: 28px; border-radius: 9px; display: grid; place-items: center;
  background: #eef6f0; color: var(--green); font-weight: 800; font-size: 13px;
}
.task-main { flex: 1; min-width: 0; }
.task-main a { color: var(--ink); font-weight: 700; }
.task-main p { margin: 2px 0 0; color: var(--muted); font-size: 13px; }
.task-time { color: var(--muted); font-size: 12px; white-space: nowrap; }

.progress-row { display: grid; grid-template-columns: 72px 1fr 46px; align-items: center; gap: 10px; margin: 12px 0; font-size: 13px; }
.bar { height: 8px; background: #eee9de; border-radius: 999px; overflow: hidden; }
.bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--green), var(--green-2)); border-radius: 999px; }

.mini-list { display: grid; gap: 6px; }
.mini {
  display: flex; align-items: center; gap: 10px; padding: 10px 8px;
  border-radius: 10px; color: var(--ink); font-size: 14px;
}
.mini:hover { background: #f6f2e8; text-decoration: none; }
.mini-week { color: var(--green); font-weight: 800; font-size: 12px; width: 28px; }
.mini-time { margin-left: auto; color: var(--muted); font-size: 12px; }

.page-head { margin: 8px 0 22px; }
.list { display: grid; gap: 8px; }
.list-row {
  display: flex; align-items: center; gap: 14px;
  background: var(--paper-2); border: 1px solid var(--line); border-radius: 14px;
  padding: 14px 16px; color: var(--ink);
}
.list-row:hover { text-decoration: none; border-color: #cfc7b6; transform: translateY(-1px); }
.week-chip {
  min-width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center;
  background: #eef6f0; color: var(--green); font-weight: 800; font-size: 12px;
}
.list-main { flex: 1; min-width: 0; }
.list-main h3 { margin: 0; font-size: 15px; }
.list-main .en { color: var(--muted); font-weight: 500; font-size: 12px; margin-left: 6px; }
.list-main p { margin: 3px 0 0; color: var(--muted); font-size: 12.5px; }

.badge {
  display: inline-block; padding: 3px 8px; border-radius: 999px;
  font-size: 11px; font-weight: 800; letter-spacing: .3px;
  background: #eee9de; color: var(--muted); text-transform: uppercase;
}
.badge.AC, .badge.solved { background: #e6f4ea; color: var(--green); }
.badge.WA, .badge.attempted { background: #fdf0e3; color: var(--amber); }
.badge.TLE, .badge.RE, .badge.CE, .badge.red { background: #fbe9e6; color: var(--red); }
.badge.hint_ac { background: #e8eff8; color: var(--blue); }
.badge.todo { background: #eee9de; color: var(--muted); }

.status-dot { font-size: 12px; color: var(--muted); }
.status-dot.done { color: var(--green); font-weight: 700; }
.status-dot.in_progress { color: var(--amber); font-weight: 700; }

.article { max-width: 860px; margin: 0 auto; }
.article-head { margin-bottom: 18px; }
.article-actions { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 24px; flex-wrap: wrap; }
.pager { display: flex; gap: 14px; flex-wrap: wrap; }

.prose { color: #2a342e; }
.prose h2 { margin: 26px 0 10px; font-size: 20px; letter-spacing: -.3px; }
.prose h3 { margin: 22px 0 8px; font-size: 17px; }
.prose p { margin: 10px 0; }
.prose ul, .prose ol { padding-left: 22px; }
.prose li { margin: 5px 0; }
.prose code { background: #efe9dc; padding: 2px 6px; border-radius: 6px; font-size: .9em; }
.prose pre {
  background: #1f2a24; color: #e9efe9; padding: 14px 16px; border-radius: 12px;
  overflow-x: auto; font-size: 13px; line-height: 1.55;
}
.prose pre code { background: transparent; padding: 0; color: inherit; }
.prose blockquote { margin: 14px 0; padding: 10px 14px; border-left: 3px solid var(--green); background: #f1f6f1; color: #3c4a41; border-radius: 0 10px 10px 0; }
.prose table { border-collapse: collapse; width: 100%; margin: 14px 0; font-size: 13.5px; }
.prose th, .prose td { border: 1px solid var(--line); padding: 7px 9px; text-align: left; }
.prose th { background: #f2ede2; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  border: 1px solid var(--line); background: #fff; color: var(--ink);
  padding: 9px 14px; border-radius: 10px; font-weight: 700; font-size: 14px;
  cursor: pointer; transition: .15s ease; font-family: inherit;
}
.btn:hover { border-color: #cfc7b6; transform: translateY(-1px); text-decoration: none; }
.btn:disabled { opacity: .55; cursor: not-allowed; transform: none; }
.btn.primary { background: linear-gradient(145deg, var(--green), var(--green-2)); color: #fff; border-color: transparent; box-shadow: 0 6px 14px rgba(31, 111, 74, .22); }
.btn.small { padding: 6px 10px; font-size: 12.5px; border-radius: 8px; }
.btn.danger { color: var(--red); border-color: #eccfc9; background: #fff8f7; }
.ghost { color: var(--muted); font-size: 13px; }
.ghost:hover { color: var(--green); }

.problem-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 18px; margin: 8px 0 20px; }
.problem-meta { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.problem-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 18px; align-items: start; }
.problem-body { max-height: calc(100vh - 120px); overflow: auto; }
.editor-card { position: sticky; top: 78px; }
.section-title { margin: 26px 0 10px; font-size: 14px; text-transform: uppercase; letter-spacing: 1px; color: var(--muted); }

.samples { display: grid; gap: 10px; }
.sample { border: 1px solid var(--line); border-radius: 12px; overflow: hidden; background: #fff; }
.sample-head { padding: 7px 12px; background: #f2ede2; font-size: 12px; font-weight: 800; color: var(--muted); }
.sample-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--line); }
.sample-cols > div { background: #fff; padding: 10px 12px; }
.sample-cols span { display: block; font-size: 11px; color: var(--muted); margin-bottom: 4px; }
.sample pre, .case-cols pre { margin: 0; font-size: 12.5px; white-space: pre-wrap; word-break: break-word; }

.hint-actions { display: flex; gap: 8px; flex-wrap: wrap; }
.hints { display: grid; gap: 10px; margin-top: 12px; }
.hint { border: 1px solid #d8e6dc; background: #f4faf5; border-radius: 12px; padding: 12px 14px; }
.hint-title { font-size: 12px; font-weight: 800; color: var(--green); margin-bottom: 6px; }

.editor-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 8px; font-size: 12px; color: var(--muted); }
.editor {
  width: 100%; min-height: 330px; resize: vertical;
  background: #1f2a24; color: #e9efe9; border: 0; border-radius: 12px;
  padding: 14px; font-size: 13px; line-height: 1.55; outline: none;
  tab-size: 4;
}
.editor-actions { display: flex; align-items: center; gap: 8px; margin-top: 10px; flex-wrap: wrap; }
.result { margin-top: 12px; }
.result-head { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.compile { background: #fbe9e6; color: #7b2a1f; padding: 10px 12px; border-radius: 10px; font-size: 12.5px; overflow: auto; white-space: pre-wrap; }
.cases { display: grid; gap: 6px; }
.case { border: 1px solid var(--line); border-radius: 10px; padding: 8px 10px; background: #fff; font-size: 13px; }
.case-name { color: var(--muted); font-size: 12px; }
.case-detail { margin-top: 6px; }
.case-detail summary { cursor: pointer; color: var(--blue); font-size: 12px; }
.case-cols { display: grid; gap: 8px; margin-top: 8px; }
.case-cols span { display: block; font-size: 11px; color: var(--muted); margin-bottom: 2px; }
.case-cols pre { background: #f5f1e7; padding: 8px; border-radius: 8px; }

.history { margin-top: 14px; border-top: 1px solid var(--line); padding-top: 10px; }
.history summary { cursor: pointer; color: var(--muted); font-size: 13px; }
.history-list { list-style: none; margin: 8px 0 0; padding: 0; display: grid; gap: 6px; font-size: 13px; }

.kpis { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-bottom: 18px; }
.kpi { background: var(--paper-2); border: 1px solid var(--line); border-radius: 14px; padding: 16px; box-shadow: var(--shadow); }
.kpi b { display: block; font-size: 26px; letter-spacing: -.5px; }
.kpi span { color: var(--muted); font-size: 12px; }

.empty { padding: 22px; text-align: center; color: var(--muted); }
.alert { padding: 10px 12px; border-radius: 10px; margin-bottom: 12px; font-size: 13px; }
.alert.bad { background: #fbe9e6; color: var(--red); }

.login-shell { min-height: 100vh; display: grid; place-items: center; padding: 24px; }
.login-card { width: 100%; max-width: 380px; background: var(--paper-2); border: 1px solid var(--line); border-radius: 20px; padding: 26px; box-shadow: var(--shadow); }
.login-brand { display: flex; align-items: center; gap: 12px; margin-bottom: 20px; }
.login-brand h1 { font-size: 22px; margin: 0; }
.login-brand p { margin: 2px 0 0; color: var(--muted); font-size: 13px; }
.stack { display: grid; gap: 12px; }
.stack label { display: grid; gap: 6px; font-size: 13px; color: var(--muted); }
.stack input { padding: 11px 12px; border: 1px solid var(--line); border-radius: 10px; font-size: 15px; font-family: inherit; background: #fff; }
.divider { display: flex; align-items: center; gap: 10px; color: var(--muted); font-size: 12px; margin: 18px 0 12px; }
.divider::before, .divider::after { content: ''; height: 1px; background: var(--line); flex: 1; }
.wechat-box { text-align: center; }
.qr-wrap { min-height: 44px; display: grid; place-items: center; }
.qr { width: 180px; height: 180px; border: 1px solid var(--line); border-radius: 10px; background: #fff; }
.login-foot { text-align: center; color: var(--muted); font-size: 12px; margin-top: 16px; }

.diag-timer { display: flex; align-items: center; gap: 10px; }
.diag-timer span { font: 700 18px/1 ui-monospace, monospace; color: var(--green); }
.diag-form { max-width: 860px; }
.diag-section { margin: 26px 0 10px; font-size: 20px; letter-spacing: -.3px; }
.diag-q { margin-bottom: 14px; }
.diag-q-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.diag-q-head h3 { margin: 0 0 4px; font-size: 17px; }
.diag-code { background: #1f2a24; color: #e9efe9; padding: 14px 16px; border-radius: 12px; overflow-x: auto; font-size: 13px; }
.diag-label { display: grid; gap: 6px; margin-top: 12px; font-size: 13px; color: var(--muted); }
.diag-label input {
  padding: 10px 12px; border: 1px solid var(--line); border-radius: 10px;
  font: 15px ui-monospace, monospace; background: #fff;
}
.diag-editor { min-height: 180px; }
.diag-why {
  width: 100%; min-height: 64px; resize: vertical; padding: 10px 12px;
  border: 1px solid var(--line); border-radius: 10px; font: 14px/1.5 inherit; background: #fff;
}
.diag-actions { display: flex; align-items: center; gap: 12px; margin: 18px 0 8px; }
.diag-score { font-size: 28px; color: var(--green); }
.diag-details { display: grid; gap: 8px; margin-top: 12px; }.review-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 560px) { .review-grid { grid-template-columns: 1fr; } }
.diag-detail { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; padding: 8px 10px; border: 1px solid var(--line); border-radius: 10px; background: #fff; }
.standard { width: 100%; font-size: 13px; color: var(--muted); }
.standard code { background: #eef6f0; color: var(--green); padding: 2px 6px; border-radius: 6px; font-weight: 700; }
.warn-inline { width: 100%; font-size: 12.5px; color: var(--amber); background: #fdf6e8; border-radius: 8px; padding: 6px 8px; }
.ref { width: 100%; margin-top: 4px; }
.ref summary { cursor: pointer; color: var(--blue); font-size: 12.5px; }
.ref pre { background: #1f2a24; color: #e9efe9; padding: 10px 12px; border-radius: 10px; overflow-x: auto; font-size: 12.5px; margin: 6px 0 0; }

.foot {
  max-width: 1120px; margin: 0 auto; padding: 22px 20px 40px;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  color: var(--muted); font-size: 12px; border-top: 1px solid var(--line);
}

@media (max-width: 900px) {
  .grid.two, .problem-grid { grid-template-columns: 1fr; }
  .hero { flex-direction: column; align-items: flex-start; }
  .hero-stats { width: 100%; }
  .stat { flex: 1; }
  .problem-body { max-height: none; }
  .editor-card { position: static; }
  .kpis { grid-template-columns: 1fr 1fr; }
  .nav-links { order: 3; width: 100%; margin-left: 0; overflow-x: auto; }
  .nav-inner { flex-wrap: wrap; }
  .nav-user { margin-left: auto; }
}
@media (max-width: 560px) {
  .wrap { padding: 18px 14px 48px; }
  .sample-cols { grid-template-columns: 1fr; }
  .kpis { grid-template-columns: 1fr; }
  .list-row { align-items: flex-start; }
  .task { align-items: flex-start; }
}

/* ---------- 学习地图 ---------- */
.map-hero { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; margin: 8px 0 20px; }
.map-now { min-width: 240px; padding: 14px 16px; background: #eef6f0; border: 1px solid #cfe3d4; border-radius: 14px; }
.map-now-label { display: block; font-size: 11px; color: var(--green); font-weight: 800; letter-spacing: 1px; }
.map-now b { display: block; margin: 4px 0 2px; font-size: 17px; }
.map-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-bottom: 18px; }
.map-stat { background: var(--paper-2); border: 1px solid var(--line); border-radius: 14px; padding: 14px 16px; box-shadow: var(--shadow); }
.map-stat b { display: block; font-size: 22px; letter-spacing: -.4px; }
.map-stat span { color: var(--muted); font-size: 12px; }
.map-stages { margin-bottom: 22px; }
.stage-flow { display: flex; align-items: stretch; gap: 8px; }
.stage { flex: 1; padding: 12px; border: 1px solid var(--line); border-radius: 12px; background: #fff; }
.stage.on { background: #f4faf5; border-color: #cfe3d4; }
.stage-weeks { font-size: 11px; font-weight: 800; color: var(--green); }
.stage b { display: block; margin: 3px 0; }
.stage p { margin: 0; font-size: 12.5px; color: var(--muted); }
.stage-arrow { display: grid; place-items: center; color: var(--muted); }
.map-section { margin: 26px 0; }
.timeline { position: relative; display: grid; gap: 12px; padding-left: 46px; }
.timeline::before { content: ''; position: absolute; left: 17px; top: 8px; bottom: 8px; width: 2px; background: var(--line); }
.tl-item { position: relative; }
.tl-dot {
  position: absolute; left: -46px; top: 14px; width: 36px; height: 36px;
  border-radius: 12px; display: grid; place-items: center; z-index: 1;
  background: #eee9de; color: var(--muted); font-weight: 800; font-size: 12px;
  border: 2px solid var(--paper);
}
.tl-item.live .tl-dot { background: #e6f4ea; color: var(--green); }
.tl-item.now .tl-dot { background: var(--green); color: #fff; box-shadow: 0 0 0 4px #d9ecdf; }
.tl-card { background: var(--paper-2); border: 1px solid var(--line); border-radius: 14px; padding: 14px 16px; }
.tl-item.now .tl-card { border-color: var(--green); box-shadow: 0 8px 24px rgba(31,111,74,.12); }
.tl-item.pending .tl-card { opacity: .78; }
.tl-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 10px; }
.tl-phase { font-size: 11px; color: var(--muted); letter-spacing: 1px; text-transform: uppercase; }
.tl-head h3 { margin: 2px 0 0; font-size: 16px; }
.tl-status { font-size: 11px; font-weight: 800; padding: 3px 8px; border-radius: 999px; white-space: nowrap; }
.tl-status.now { background: #e6f4ea; color: var(--green); }
.tl-status.live { background: #eef6f0; color: var(--green); }
.tl-status.pending { background: #eee9de; color: var(--muted); }
.tl-lesson { margin: 8px 0; font-size: 13px; color: var(--muted); }
.tl-row { display: flex; gap: 8px; font-size: 13px; margin: 4px 0; }
.tl-label { color: var(--muted); min-width: 32px; }
.tl-links { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.mini-link { display: inline-flex; align-items: center; gap: 6px; font-size: 12.5px; padding: 4px 8px; border: 1px solid var(--line); border-radius: 8px; background: #fff; color: var(--ink); }
.mini-link:hover { text-decoration: none; border-color: #cfc7b6; }
.lesson-link { margin-top: 8px; color: var(--green); border-color: #cfe3d4; background: #f4faf5; }
.mindmap { display: grid; grid-template-columns: 180px 1fr; gap: 18px; align-items: start; }
.mind-center { background: linear-gradient(145deg, var(--green), var(--green-2)); color: #fff; border-radius: 16px; padding: 18px; text-align: center; box-shadow: 0 10px 24px rgba(31,111,74,.22); position: sticky; top: 84px; }
.mind-center b { display: block; font-size: 24px; }
.mind-center span { display: block; font-size: 11.5px; opacity: .85; margin-top: 4px; }
.mind-branches { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.mind-branch { background: var(--paper-2); border: 1px solid var(--line); border-radius: 14px; padding: 14px; }
.mind-head { display: flex; align-items: center; gap: 8px; }
.mind-icon { width: 28px; height: 28px; border-radius: 9px; display: grid; place-items: center; background: #eef6f0; color: var(--green); font-weight: 800; }
.mind-branch ul { list-style: none; margin: 10px 0 0; padding: 0; display: grid; gap: 6px; }
.skill { display: flex; align-items: center; gap: 8px; font-size: 13px; padding: 5px 6px; border-radius: 8px; }
.skill-dot { width: 8px; height: 8px; border-radius: 999px; background: #d8d2c5; flex: none; }
.skill.done { color: var(--green); }
.skill.done .skill-dot { background: var(--green); }
.skill.current { background: #f4faf5; color: var(--ink); font-weight: 700; }
.skill.current .skill-dot { background: var(--amber); }
.skill-week { margin-left: auto; color: var(--muted); font-size: 11px; }
.checklist { margin: 0; padding-left: 20px; }
.checklist li { margin: 8px 0; }
@media (max-width: 900px) {
  .map-hero { flex-direction: column; align-items: flex-start; }
  .map-stats { grid-template-columns: 1fr 1fr; }
  .stage-flow { flex-wrap: wrap; }
  .stage-arrow { display: none; }
  .mindmap { grid-template-columns: 1fr; }
  .mind-center { position: static; }
  .mind-branches { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .map-stats { grid-template-columns: 1fr; }
  .timeline { padding-left: 38px; }
  .timeline::before { left: 13px; }
  .tl-dot { left: -38px; width: 30px; height: 30px; font-size: 11px; }
}