:root {
  /* Dark default (tech style) */
  --bg: #0b0f19;
  --fg: #e5e7eb;
  --muted: #9aa4b2;
  --line: #1e2633;
  --accent: #a855f7; /* purple */
  --soft: rgba(168, 85, 247, 0.08);
  --card: #0f1524;
  --radius: 12px;
  --font: system-ui, -apple-system, Segoe UI, Roboto, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

/* Light scheme (if user prefers light and no explicit override) */
@media (prefers-color-scheme: light) {
  :root {
    --bg: #ffffff;
    --fg: #1f2328;
    --muted: #6b7280;
    --line: #e5e7eb;
    --accent: #6d28d9; /* purple (darker in light) */
    --soft: #f5f3ff;
    --card: #ffffff;
  }
}

/* Explicit override by toggle */
html[data-theme="dark"] {
  --bg: #0b0f19;
  --fg: #e5e7eb;
  --muted: #9aa4b2;
  --line: #1e2633;
  --accent: #a855f7;
  --soft: rgba(168, 85, 247, 0.08);
  --card: #0f1524;
}
html[data-theme="light"] {
  --bg: #ffffff;
  --fg: #1f2328;
  --muted: #6b7280;
  --line: #e5e7eb;
  --accent: #6d28d9;
  --soft: #f5f3ff;
  --card: #ffffff;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 15.5px/1.65 var(--font); }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 2px; }
.wrap { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.muted { color: var(--muted); }
.small { font-size: 12.5px; }
.sep { opacity: .6; margin: 0 .4em; }
.mono { font-family: var(--mono); letter-spacing: .2px; }

.top { position: sticky; top: 0; z-index: 20; backdrop-filter: saturate(150%) blur(8px); background: color-mix(in oklab, var(--bg) 92%, transparent); border-bottom: 1px solid var(--line); }
.top-in { display: flex; align-items: center; gap: 16px; height: 60px; }
.brand { font-weight: 800; font-size: 18px; color: var(--fg); white-space: nowrap; }
.cats { display: flex; gap: 14px; overflow-x: auto; flex: 1; scrollbar-width: none; }
.cats::-webkit-scrollbar { display: none; }
.cats a { color: var(--muted); white-space: nowrap; font-size: 14px; }
.cats a.home { color: var(--fg); font-weight: 600; }
.search input { width: 200px; max-width: 38vw; padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; font: inherit; font-size: 14px; color: var(--fg); background: var(--bg); outline: none; }
.search input::placeholder { color: var(--muted); }
.langs { display: flex; gap: 6px; font-size: 13px; }
.langs a { color: var(--muted); }
.langs a.on { color: var(--fg); font-weight: 700; }
.toggle { width: 32px; height: 32px; border-radius: 999px; border: 1px solid var(--line); background: var(--bg); color: var(--accent); display: inline-grid; place-items: center; }
.toggle:hover { filter: brightness(1.1); }

.grid { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 32px; padding-top: 22px; padding-bottom: 36px; }
.h1 { font-size: 26px; line-height: 1.25; margin: 0 0 14px; letter-spacing: .2px; }
.intro { padding: 12px 14px; background: var(--soft); border-radius: var(--radius); margin: 0 0 18px; border: 1px solid color-mix(in oklab, var(--accent) 25%, transparent); }
.crumbs { font-size: 13px; color: var(--muted); margin: 0 0 8px; }
.day { margin: 0 0 8px; }
.day-h { font-size: 16px; color: var(--muted); margin: 10px 0 6px; font-family: var(--mono); }

.item { padding: 14px 0; border-bottom: 1px solid var(--line); }
.item h2 { font-size: 18px; line-height: 1.35; margin: 0 0 4px; }
.item h2 a { color: var(--fg); }
.item .sum { margin: 4px 0 0; }
.meta { color: var(--muted); font-size: 13px; }

.post .lead { font-size: 17px; color: color-mix(in oklab, var(--fg) 85%, var(--muted)); margin-top: 6px; }
.post .body { margin-top: 14px; }
.post .body h2, .post .body h3 { margin: 18px 0 8px; }
.post .src { margin-top: 18px; padding-top: 12px; border-top: 1px dashed var(--line); }
.tags { margin-top: 10px; }
.tag { display: inline-block; padding: 2px 8px; border: 1px solid var(--line); border-radius: 999px; font-size: 12px; color: var(--muted); }
.related { margin-top: 26px; }
.related h3 { margin: 0 0 8px; font-size: 15px; }

.side .box { border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 16px; margin-bottom: 14px; background: var(--card); }
.side h3 { margin: 0 0 10px; font-size: 15px; letter-spacing: .2px; }
.promo { background: linear-gradient(180deg, var(--soft), transparent 120%); border-color: transparent !important; }
.promo .btn { margin-top: 6px; }
.btn { display: inline-block; padding: 7px 14px; border-radius: 999px; background: var(--accent); color: #fff; font-weight: 700; font-size: 13px; box-shadow: 0 0 0 rgba(168,85,247,0.0), 0 0 12px rgba(168,85,247,0.35); }
.btn:hover { text-decoration: none; filter: brightness(1.05); }
.plain { list-style: none; margin: 0; padding: 0; }
.plain li { padding: 4px 0; }

.pager { display: flex; justify-content: space-between; align-items: center; margin-top: 18px; font-size: 14px; }
.foot { border-top: 1px solid var(--line); padding: 18px 0; color: var(--muted); font-size: 13px; }

@media (max-width: 900px) {
  .grid { grid-template-columns: minmax(0, 1fr); gap: 20px; }
  .search { display: none; }
  .top-in { height: 56px; }
  .h1 { font-size: 22px; }
}