/* ============ 设计变量 ============ */
:root {
  --bg: #f4f6fb;
  --bg-soft: #eef1f8;
  --card: #ffffff;
  --card-hover: #ffffff;
  --text: #1b1f2a;
  --text-soft: #5b6478;
  --text-faint: #8b93a7;
  --line: #e3e8f2;
  --brand: #4f6df5;
  --brand-2: #8b5cf6;
  --shadow: 0 1px 2px rgba(20, 30, 60, .04), 0 8px 24px -12px rgba(20, 30, 60, .18);
  --shadow-hover: 0 2px 4px rgba(20, 30, 60, .05), 0 16px 40px -16px rgba(40, 60, 140, .28);
  --radius: 16px;
  --topbar-bg: rgba(255, 255, 255, .72);
  --code-bg: #f0f3f9;
}

html[data-theme="dark"] {
  --bg: #0b0d12;
  --bg-soft: #12151c;
  --card: #151922;
  --card-hover: #1a1f2b;
  --text: #e8ecf5;
  --text-soft: #9aa4ba;
  --text-faint: #6b748a;
  --line: #232936;
  --brand: #6d8bff;
  --brand-2: #a78bfa;
  --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px -12px rgba(0, 0, 0, .6);
  --shadow-hover: 0 2px 6px rgba(0, 0, 0, .35), 0 18px 44px -18px rgba(80, 110, 255, .35);
  --topbar-bg: rgba(12, 15, 21, .72);
  --code-bg: #1b2130;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  overflow-x: hidden;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
  min-height: 100vh;
  transition: background .3s ease, color .3s ease;
}

/* 背景光斑 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(760px 420px at 12% -8%, rgba(79, 109, 245, .13), transparent 60%),
    radial-gradient(640px 380px at 88% 4%, rgba(139, 92, 246, .11), transparent 62%);
}
html[data-theme="dark"] body::before {
  background:
    radial-gradient(760px 420px at 12% -8%, rgba(79, 109, 245, .20), transparent 60%),
    radial-gradient(640px 380px at 88% 4%, rgba(139, 92, 246, .16), transparent 62%);
}

/* ============ 顶栏 ============ */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--topbar-bg);
  backdrop-filter: saturate(180%) blur(18px);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  border-bottom: 1px solid var(--line);
}

.topbar-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 650;
  letter-spacing: .2px;
  flex-shrink: 0;
}
.brand-mark {
  width: 30px; height: 30px;
  border-radius: 9px;
  display: grid; place-items: center;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff;
  font-size: 15px;
  font-weight: 800;
  box-shadow: 0 4px 12px -4px rgba(79, 109, 245, .55);
}
.brand-text em { font-style: normal; color: var(--text-soft); font-weight: 500; }

.tabs { display: flex; gap: 4px; }
.tab {
  border: 0;
  background: transparent;
  color: var(--text-soft);
  font-size: 14.5px;
  font-weight: 550;
  padding: 7px 15px;
  border-radius: 10px;
  cursor: pointer;
  transition: all .18s ease;
  font-family: inherit;
}
.tab:hover { color: var(--text); background: var(--bg-soft); }
.tab.is-active { color: var(--brand); background: color-mix(in srgb, var(--brand) 11%, transparent); }

.topbar-right { margin-left: auto; display: flex; align-items: center; gap: 10px; }

.search-wrap {
  position: relative;
  display: flex;
  align-items: center;
}
.search-icon {
  position: absolute; left: 11px;
  width: 15px; height: 15px;
  fill: none; stroke: var(--text-faint); stroke-width: 2;
  stroke-linecap: round; pointer-events: none;
}
#search {
  width: 220px;
  height: 36px;
  padding: 0 34px 0 33px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 13.5px;
  font-family: inherit;
  outline: none;
  transition: all .2s ease;
}
#search::placeholder { color: var(--text-faint); }
#search:focus {
  border-color: var(--brand);
  background: var(--card);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--brand) 14%, transparent);
  width: 260px;
}
.search-wrap kbd {
  position: absolute; right: 9px;
  font-size: 11px; color: var(--text-faint);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 0 5px;
  line-height: 17px;
  font-family: inherit;
  background: var(--card);
  pointer-events: none;
}
#search:focus + kbd { display: none; }

.icon-btn {
  width: 36px; height: 36px;
  display: grid; place-items: center;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  color: var(--text-soft);
  cursor: pointer;
  transition: all .18s ease;
}
.icon-btn:hover { color: var(--brand); border-color: color-mix(in srgb, var(--brand) 40%, var(--line)); }
.icon-btn svg { width: 17px; height: 17px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.i-moon { display: none; }
html[data-theme="dark"] .i-sun { display: none; }
html[data-theme="dark"] .i-moon { display: block; }

/* ============ 主体 ============ */
#main {
  position: relative;
  z-index: 1;
  max-width: 1180px;
  margin: 0 auto;
  padding: 44px 24px 80px;
}

.hero { margin-bottom: 34px; }
.hero h1 {
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 750;
  letter-spacing: -.8px;
  margin: 0 0 8px;
}
.grad {
  background: linear-gradient(120deg, var(--brand), var(--brand-2) 70%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub { margin: 0; color: var(--text-soft); font-size: 14.5px; }

/* ============ 分组与卡片 ============ */
.groups { display: flex; flex-direction: column; gap: 34px; }

.group-title {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 13px;
  font-weight: 650;
  letter-spacing: .4px;
  color: var(--text-faint);
  text-transform: uppercase;
  margin: 0 0 14px;
}
.group-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--line), transparent);
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 14px;
}

.card {
  position: relative;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 13px;
  padding: 15px 17px;
  border-radius: var(--radius);
  background: var(--card);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  text-decoration: none;
  color: inherit;
  overflow: hidden;
  transition: transform .2s cubic-bezier(.2, .8, .3, 1), box-shadow .2s ease, border-color .2s ease, background .2s ease;
}
.card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(120deg, color-mix(in srgb, var(--brand) 0%, transparent), transparent);
  opacity: 0;
  transition: opacity .25s ease;
  pointer-events: none;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
  border-color: color-mix(in srgb, var(--brand) 32%, var(--line));
  background: var(--card-hover);
}
.card:hover::after { opacity: 1; background: linear-gradient(120deg, color-mix(in srgb, var(--brand) 6%, transparent), transparent 70%); }
.card:active { transform: translateY(-1px) scale(.995); }

.card-icon {
  flex-shrink: 0;
  width: 42px; height: 42px;
  border-radius: 12px;
  display: grid; place-items: center;
  font-size: 20px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  transition: transform .2s ease;
}
.card:hover .card-icon { transform: scale(1.06) rotate(-2deg); }

.card-body { min-width: 0; flex: 1; }
.card-name {
  display: block;
  font-size: 14.5px;
  font-weight: 600;
  letter-spacing: -.1px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.card-desc {
  display: block;
  font-size: 12.5px;
  color: var(--text-faint);
  margin-top: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.card-arrow {
  flex-shrink: 0;
  width: 15px; height: 15px;
  stroke: var(--text-faint);
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: 0;
  transform: translateX(-4px);
  transition: all .2s ease;
}
.card:hover .card-arrow { opacity: 1; transform: translateX(0); stroke: var(--brand); }

/* ============ 博客 ============ */
.post-list { display: flex; flex-direction: column; gap: 12px; }

.post-item {
  display: block;
  padding: 20px 22px;
  border-radius: var(--radius);
  background: var(--card);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  text-decoration: none;
  color: inherit;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.post-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
  border-color: color-mix(in srgb, var(--brand) 30%, var(--line));
}
.post-item h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 650;
  letter-spacing: -.2px;
}
.post-item p {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-soft);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-top: 11px;
  font-size: 12.5px;
  color: var(--text-faint);
}
.tag {
  padding: 1px 9px;
  border-radius: 99px;
  background: color-mix(in srgb, var(--brand) 10%, transparent);
  color: var(--brand);
  font-size: 11.5px;
  font-weight: 550;
}

/* ============ 文章详情 ============ */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-bottom: 22px;
  border: 0;
  background: transparent;
  color: var(--text-soft);
  font-size: 13.5px;
  font-family: inherit;
  cursor: pointer;
  padding: 6px 0;
  transition: color .18s ease;
}
.back-link:hover { color: var(--brand); }
.back-link svg { width: 15px; height: 15px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

.article {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 40px 44px 46px;
  box-shadow: var(--shadow);
}
.article-head { border-bottom: 1px solid var(--line); padding-bottom: 20px; margin-bottom: 26px; }
.article-head h1 { margin: 0 0 10px; font-size: 28px; font-weight: 720; letter-spacing: -.6px; line-height: 1.35; }
.article-meta { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-size: 13px; color: var(--text-faint); }

/* Markdown 排版 */
.markdown { font-size: 15.5px; line-height: 1.85; color: var(--text); }
.markdown > *:first-child { margin-top: 0; }
.markdown h1, .markdown h2, .markdown h3, .markdown h4 {
  margin: 1.9em 0 .7em;
  font-weight: 680;
  letter-spacing: -.3px;
  line-height: 1.4;
}
.markdown h1 { font-size: 24px; }
.markdown h2 { font-size: 20px; padding-bottom: .35em; border-bottom: 1px solid var(--line); }
.markdown h3 { font-size: 17px; }
.markdown p { margin: .9em 0; }
.markdown a { color: var(--brand); text-decoration: none; border-bottom: 1px solid color-mix(in srgb, var(--brand) 35%, transparent); }
.markdown a:hover { border-bottom-color: var(--brand); }
.markdown ul, .markdown ol { padding-left: 1.4em; margin: .9em 0; }
.markdown li { margin: .35em 0; }
.markdown li::marker { color: var(--text-faint); }
.markdown blockquote {
  margin: 1.2em 0;
  padding: .7em 1.1em;
  border-left: 3px solid var(--brand);
  background: color-mix(in srgb, var(--brand) 6%, transparent);
  border-radius: 0 10px 10px 0;
  color: var(--text-soft);
}
.markdown blockquote p { margin: .3em 0; }
.markdown .callout-title {
  font-weight: 650;
  color: var(--text);
  font-size: 14.5px;
  margin-bottom: .5em;
  letter-spacing: -.1px;
}
.markdown .wikilink {
  border-bottom: 1px dashed color-mix(in srgb, var(--brand) 60%, transparent);
  text-decoration: none;
}
.markdown .wikilink:hover { border-bottom-style: solid; }
.markdown code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .88em;
  background: var(--code-bg);
  padding: .16em .42em;
  border-radius: 5px;
  border: 1px solid var(--line);
}
.markdown pre {
  background: var(--code-bg);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  overflow-x: auto;
  margin: 1.2em 0;
  line-height: 1.6;
}
.markdown pre code { background: none; border: 0; padding: 0; font-size: 13.5px; }
.markdown img { max-width: 100%; border-radius: 12px; border: 1px solid var(--line); }
.markdown hr { border: 0; border-top: 1px solid var(--line); margin: 2em 0; }
.markdown table { width: 100%; border-collapse: collapse; margin: 1.2em 0; font-size: 14px; table-layout: auto; }
.markdown th, .markdown td { border: 1px solid var(--line); padding: 9px 13px; text-align: left; }
.markdown th { background: var(--bg-soft); font-weight: 600; }
.markdown tr:nth-child(even) td { background: color-mix(in srgb, var(--bg-soft) 55%, transparent); }

/* ============ 空状态 ============ */
.empty { text-align: center; padding: 70px 20px; color: var(--text-soft); }
.empty-emoji { font-size: 40px; margin-bottom: 12px; opacity: .85; }
.empty p { margin: 6px 0; font-size: 14.5px; }
.empty-tip { color: var(--text-faint); font-size: 13px !important; }
.empty-tip code { background: var(--code-bg); padding: 2px 7px; border-radius: 5px; font-size: 12.5px; border: 1px solid var(--line); }
.btn-ghost {
  margin-top: 14px;
  padding: 8px 18px;
  border-radius: 9px;
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--text-soft);
  font-family: inherit;
  font-size: 13.5px;
  cursor: pointer;
  transition: all .18s ease;
}
.btn-ghost:hover { color: var(--brand); border-color: color-mix(in srgb, var(--brand) 45%, var(--line)); }

/* ============ 页脚 ============ */
.footer {
  position: relative;
  z-index: 1;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px 40px;
  font-size: 12.5px;
  color: var(--text-faint);
  display: flex;
  gap: 6px;
  align-items: center;
}
.footer .dot { opacity: .5; }

/* ============ 入场动画 ============ */
/* 只做位移，不碰 opacity —— 动画被跳过时内容依然完整可见 */
@keyframes rise {
  from { transform: translateY(8px); }
  to { transform: none; }
}
.card, .post-item { animation: rise .4s cubic-bezier(.2, .8, .3, 1); }
.cards .card:nth-child(1) { animation-delay: .02s; }
.cards .card:nth-child(2) { animation-delay: .05s; }
.cards .card:nth-child(3) { animation-delay: .08s; }
.cards .card:nth-child(4) { animation-delay: .11s; }
.cards .card:nth-child(5) { animation-delay: .14s; }
.cards .card:nth-child(6) { animation-delay: .17s; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}

/* ============ 响应式 ============ */
@media (max-width: 860px) {
  .topbar-inner { height: auto; padding: 12px 16px; flex-wrap: wrap; gap: 12px; }
  .topbar-right { flex: 1 1 100%; min-width: 0; }
  .search-wrap { flex: 1; }
  #search { width: 100%; }
  #search:focus { width: 100%; }
  .brand-text em { display: none; }
  #main { padding: 28px 16px 60px; }
  .cards { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
  .card { padding: 12px 13px; gap: 10px; }
  .card-icon { width: 36px; height: 36px; font-size: 17px; border-radius: 10px; }
  .card-name { font-size: 13.5px; }
  .card-desc { font-size: 11.5px; }
  .card-arrow { display: none; }
  .article { padding: 24px 20px 30px; border-radius: 16px; }
  .article-head h1 { font-size: 22px; }
  .markdown { font-size: 15px; }
  .footer { padding: 0 16px 30px; }
}

@media (max-width: 420px) {
  .card { padding: 11px 12px; }
  .card-desc { font-size: 11px; }
}