/* -------- Base -------- */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, 'Noto Sans', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  line-height: 1.6;
  background: var(--bg);
  color: var(--fg);
}
:root {
  --bg: #0b0c10;
  --surface: #111217;
  --border: #1d1f29;
  --muted: #8c93a3;
  --fg: #e6e9ef;
  --brand: #6ea8fe;
  --shadow: 0 8px 24px rgba(0,0,0,.24);
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6f7fb;
    --surface: #ffffff;
    --border: #e8ebf3;
    --muted: #5b6475;
    --fg: #171923;
    --brand: #2563eb;
    --shadow: 0 8px 24px rgba(0,0,0,.08);
  }
}
.container { width: min(1200px, 94vw); margin-inline: auto; padding-inline: 12px; }

/* -------- Header -------- */
.site-header { position: sticky; top: 0; z-index: 10; backdrop-filter: saturate(140%) blur(8px); background: color-mix(in oklab, var(--surface) 75%, transparent); border-bottom: 1px solid var(--border);}
.header-inner { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 12px; min-height: 56px; }
.brand { font-weight: 800; letter-spacing: .4px; font-size: 18px; }
.tabs { display: flex; gap: 8px; justify-content: center; }
.tab-btn { appearance: none; border: 1px solid var(--border); background: linear-gradient(180deg, color-mix(in oklab, var(--surface) 90%, transparent), var(--surface)); color: var(--fg); padding: 8px 14px; border-radius: 999px; cursor: pointer; transition: transform .06s ease, background .2s ease, border-color .2s ease, box-shadow .2s ease; box-shadow: 0 1px 0 rgba(255,255,255,.04) inset, 0 1px 1px rgba(0,0,0,.12); }
.tab-btn:hover { transform: translateY(-1px); }
.tab-btn[aria-selected="true"] { border-color: color-mix(in oklab, var(--brand) 40%, var(--border)); background: linear-gradient(180deg, color-mix(in oklab, var(--brand) 35%, var(--surface)), var(--surface)); box-shadow: 0 0 0 3px color-mix(in oklab, var(--brand) 18%, transparent); }

/* -------- Panels & Cards -------- */
.section-title { margin: 28px 0 16px; font-size: 22px; }
.panel { padding-block: 6px 28px; }
.panel[hidden] { display: none; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 16px 18px; box-shadow: var(--shadow); margin-bottom: 16px; }
.card-title { margin: 0 0 6px; font-size: 18px; }
.card-meta { margin: 0 0 12px; color: var(--muted); font-size: 14px; }
.card-body { margin: 0 0 12px; }

/* -------- Notes layout -------- */
.notes-layout { display: grid; grid-template-columns: 300px 1fr; gap: 16px; }
.notes-tree { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 10px; height: calc(80vh); overflow: auto; }
.tree-toolbar { display: grid; grid-template-columns: 1fr auto auto; gap: 8px; margin-bottom: 8px; }
.tree { margin: 0; padding-left: 12px; list-style: none; font-size: 14px; }
.tree li { margin: 3px 0; }
.tree .dir > .entry { cursor: pointer; user-select: none; }
.entry { display: inline-flex; align-items: center; gap: 6px; padding: 2px 6px; border-radius: 6px; }
.entry:hover { background: color-mix(in oklab, var(--brand) 20%, transparent); }
.badge { font-size: 10px; padding: 0 6px; border-radius: 999px; border: 1px solid var(--border); color: var(--muted); }

.notes-viewer { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 0; min-height: calc(80vh); overflow: hidden; display: flex; flex-direction: column; }
.note-header { padding: 10px 14px; border-bottom: 1px solid var(--border); color: var(--muted); font-size: 13px; }
#note-content { padding: 18px 20px; overflow: auto; flex: 1; }

/* -------- Prose (Markdown) -------- */
.prose { line-height: 1.75; }
.prose h1, .prose h2, .prose h3 { margin: 1.2em 0 .6em; }
.prose h1 { font-size: 28px; }
.prose h2 { font-size: 22px; }
.prose h3 { font-size: 18px; }
.prose p { margin: .8em 0; }
.prose code { padding: 2px 6px; border-radius: 6px; background: #0003; }
.prose pre { padding: 12px; background: #0005; border: 1px solid var(--border); border-radius: 12px; overflow: auto; }
.prose blockquote { margin: .8em 0; padding: .6em 1em; border-left: 3px solid var(--brand); background: #0002; }
.prose table { width: 100%; border-collapse: collapse; margin: 1em 0; }
.prose th, .prose td { border: 1px solid var(--border); padding: 6px 8px; }
.prose a { color: var(--brand); text-decoration: none; border-bottom: 1px dashed color-mix(in oklab, var(--brand) 60%, transparent); }
.prose img { max-width: 100%; display: block; margin: 8px 0; border-radius: 8px; border: 1px solid var(--border); }
.prose ul, .prose ol { padding-left: 1.2em; margin: .6em 0; }
.kbd { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; background: #0003; padding: 1px 6px; border-radius: 6px; border: 1px solid var(--border); }

/* -------- Help -------- */
.help { margin-top: 16px; border: 1px dashed var(--border); padding: 10px 14px; border-radius: 12px; color: var(--muted); }

@media (max-width: 960px) {
  .notes-layout { grid-template-columns: 1fr; }
  .notes-tree { height: auto; max-height: 40vh; }
}