/* ============================================================
   book.imoons.cn — 全新设计系统 (2026-09-18 UI 重构 v2)
   深空科技博客: 深底 + 玻璃 + 渐变光 + 精致排版
   设计参考: Vercel / Linear 级内容优先质感
   ============================================================ */

:root {
  /* 主色 */
  --accent: #6ea8ff;
  --accent-2: #22d3ee;
  --accent-3: #a78bfa;
  --accent-soft: rgba(110, 168, 255, 0.12);
  --accent-2-soft: rgba(34, 211, 238, 0.10);
  --grad: linear-gradient(135deg, #6ea8ff 0%, #22d3ee 50%, #a78bfa 100%);
  --grad-soft: linear-gradient(135deg, rgba(110,168,255,.18), rgba(34,211,238,.10));

  /* 深空底 */
  --bg-0: #05070d;
  --bg-1: #0a0e16;
  --bg-2: #10151f;
  --bg-3: #161d2b;
  --bg-hover: #1a2233;

  /* 文字 */
  --text-1: #e8ecf4;
  --text-2: #9aa7bb;
  --text-3: #64748b;
  --text-4: #3b4759;

  /* 线条 */
  --line: rgba(148, 163, 184, 0.10);
  --line-strong: rgba(148, 163, 184, 0.18);
  --line-accent: rgba(110, 168, 255, 0.35);

  /* 阴影 / 光 */
  --shadow-sm: 0 1px 2px rgba(0,0,0,.3), 0 2px 8px rgba(0,0,0,.2);
  --shadow: 0 4px 16px rgba(0,0,0,.3);
  --shadow-md: 0 10px 32px rgba(0,0,0,.38);
  --shadow-lg: 0 20px 60px rgba(0,0,0,.5);
  --glow: 0 0 24px rgba(110, 168, 255, 0.22);
  --glow-2: 0 0 24px rgba(34, 211, 238, 0.18);

  /* 尺寸 */
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --nav-h: 64px;
  --max-w: 1200px;
  --content-w: 740px;

  /* 动效 */
  --ease: cubic-bezier(.4,0,.2,1);
  --ease-out: cubic-bezier(0,0,.2,1);
  --spring: cubic-bezier(.34,1.56,.64,1);
  --dur: 150ms;
  --dur-md: 260ms;

  /* 字体 */
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
          "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
}

/* ========== 浅色主题 (v2) ========== */
html[data-theme="light"] {
  --accent: #2563eb;
  --accent-2: #0891b2;
  --accent-3: #7c3aed;
  --accent-soft: rgba(37, 99, 235, 0.10);
  --accent-2-soft: rgba(8, 145, 178, 0.08);
  --grad: linear-gradient(135deg, #2563eb 0%, #0891b2 50%, #7c3aed 100%);
  --grad-soft: linear-gradient(135deg, rgba(37,99,235,.10), rgba(8,145,178,.06));

  --bg-0: #f4f6fb;
  --bg-1: #ffffff;
  --bg-2: #ffffff;
  --bg-3: #eef2f8;
  --bg-hover: #e6ecf5;

  --text-1: #0f172a;
  --text-2: #475569;
  --text-3: #64748b;
  --text-4: #94a3b8;

  --line: rgba(15, 23, 42, 0.08);
  --line-strong: rgba(15, 23, 42, 0.14);
  --line-accent: rgba(37, 99, 235, 0.35);

  --shadow-sm: 0 1px 2px rgba(15,23,42,.04), 0 2px 8px rgba(15,23,42,.05);
  --shadow: 0 4px 16px rgba(15,23,42,.07);
  --shadow-md: 0 10px 32px rgba(15,23,42,.10);
  --shadow-lg: 0 20px 60px rgba(15,23,42,.14);
  --glow: 0 0 24px rgba(37, 99, 235, 0.16);
  --glow-2: 0 0 24px rgba(8, 145, 178, 0.12);
}

/* 浅色背景光晕 */
html[data-theme="light"] body::before {
  background:
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(37,99,235,.10), transparent 60%),
    radial-gradient(ellipse 50% 40% at 90% 5%, rgba(8,145,178,.06), transparent 55%),
    radial-gradient(ellipse 50% 40% at 8% 90%, rgba(124,58,237,.05), transparent 55%),
    var(--bg-1);
}
html[data-theme="light"] body::after {
  background-image:
    linear-gradient(rgba(15,23,42,.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15,23,42,.05) 1px, transparent 1px);
}

/* 浅色导航 */
html[data-theme="light"] .nav {
  background: rgba(255, 255, 255, 0.78);
}

/* 浅色 Hero 标题渐变 */
html[data-theme="light"] .hero h1 {
  background: linear-gradient(135deg, #0f172a 0%, #1d4ed8 60%, #0e7490 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* 浅色渐变封面文字保持白字 (渐变底本身深色) */
html[data-theme="light"] .post-grad-cat,
html[data-theme="light"] .article-cover-grad .post-grad-cat {
  color: rgba(255, 255, 255, 0.92);
}

/* 浅色页脚 */
html[data-theme="light"] .footer {
  background: var(--bg-0);
  border-top: 1px solid var(--line);
}
html[data-theme="light"] .footer::before {
  background: linear-gradient(90deg, transparent, rgba(37,99,235,.4), rgba(8,145,178,.4), transparent);
}
html[data-theme="light"] .footer h4 { color: var(--text-1); }
html[data-theme="light"] .footer p { color: var(--text-3); }
html[data-theme="light"] .footer-links a { color: var(--text-2); }
html[data-theme="light"] .footer-bottom {
  border-top: 1px solid var(--line);
  color: var(--text-3);
}

/* ========== 基础 ========== */
*,*::before,*::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  background: var(--bg-1);
  color: var(--text-1);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background .3s var(--ease), color .3s var(--ease);
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { cursor: pointer; font: inherit; border: none; background: none; color: inherit; }
ul,ol { list-style: none; }
::selection { background: rgba(110,168,255,.3); color: var(--text-1); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 6px; }

/* 全站背景光晕 + 网格 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(110,168,255,.16), transparent 60%),
    radial-gradient(ellipse 50% 40% at 90% 5%, rgba(34,211,238,.09), transparent 55%),
    radial-gradient(ellipse 50% 40% at 8% 90%, rgba(167,139,250,.08), transparent 55%),
    var(--bg-1);
}
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(148,163,184,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148,163,184,.035) 1px, transparent 1px);
  background-size: 46px 46px;
  mask-image: radial-gradient(ellipse 85% 65% at 50% 0%, black 25%, transparent 72%);
  -webkit-mask-image: radial-gradient(ellipse 85% 65% at 50% 0%, black 25%, transparent 72%);
}

.container { max-width: var(--max-w); margin-inline: auto; padding-inline: 1.5rem; }
.container-narrow { max-width: var(--content-w); margin-inline: auto; padding-inline: 1.25rem; }
.section { padding-block: 3.5rem; }

/* ========== 顶部进度条 ========== */
.reading-bar {
  position: fixed;
  top: 0; left: 0;
  height: 3px;
  width: 0;
  z-index: 2000;
  background: var(--grad);
  box-shadow: 0 0 14px rgba(110,168,255,.5);
  pointer-events: none;
}

/* ========== 导航 ========== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(10, 14, 22, 0.72);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--line);
  transition: background .3s var(--ease), border-color .3s var(--ease), box-shadow .3s var(--ease);
}
.nav.scrolled { box-shadow: 0 10px 40px rgba(0,0,0,.35); }
.nav-inner {
  max-width: var(--max-w);
  margin-inline: auto;
  min-height: var(--nav-h);
  padding-inline: 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.75rem;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 800;
  font-size: 1.05rem;
  flex-shrink: 0;
}
.nav-logo img { width: 34px; height: 34px; border-radius: 50%; border: 2px solid var(--line-strong); object-fit: cover; }
.nav-logo-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  letter-spacing: -0.02em;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.4rem;
  flex: 1;
}
.nav-menu a {
  position: relative;
  font-size: .92rem;
  color: var(--text-2);
  font-weight: 500;
  padding: 0.4rem 0;
  transition: color var(--dur) var(--ease);
}
.nav-menu a:hover { color: var(--text-1); }
.nav-menu a.active { color: var(--text-1); font-weight: 600; }
.nav-menu a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -2px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--grad);
  transform: translateX(-50%);
  transition: width .25s var(--ease);
}
.nav-menu a:hover::after, .nav-menu a.active::after { width: 100%; }
.nav-actions { display: flex; align-items: center; gap: 0.4rem; }
.nav-btn {
  width: 38px; height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  color: var(--text-2);
  transition: all .2s var(--ease);
}
.nav-btn:hover { color: var(--text-1); background: var(--bg-3); transform: translateY(-1px); }
.icon-sun { display: none; }
.icon-moon { display: block; }
html[data-theme="dark"] .icon-sun { display: block; }
html[data-theme="dark"] .icon-moon { display: none; }
.nav-toggle { display: none !important; }

/* ========== Hero ========== */
.hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--nav-h) + 4.5rem) 1.5rem 4rem;
  text-align: center;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35em 1.15em;
  margin-bottom: 1.6rem;
  font-size: .8rem;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--accent-2);
  background: var(--grad-soft);
  border: 1px solid rgba(34, 211, 238, .25);
  border-radius: 999px;
  backdrop-filter: blur(10px);
}
.hero-badge-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--accent-2);
  box-shadow: 0 0 12px var(--accent-2), 0 0 22px rgba(34,211,238,.4);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%,100%{opacity:1;transform:scale(1)} 50%{opacity:.55;transform:scale(.8)} }
.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.2rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.08;
  margin: 0 0 1.2rem;
  background: linear-gradient(135deg, #f3f6fb 0%, #a9c5ef 55%, #67e8f9 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.hero-desc {
  color: var(--text-2);
  font-size: 1.12rem;
  line-height: 1.75;
  max-width: 560px;
  margin: 0 auto 2.2rem;
}
.hero-btns { display: flex; gap: 0.8rem; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75em 1.6em;
  border-radius: 12px;
  font-size: .94rem;
  font-weight: 600;
  transition: all .25s var(--ease);
  position: relative;
  overflow: hidden;
}
.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 8px 24px rgba(110,168,255,.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(110,168,255,.5), var(--glow); }
.btn-primary::after {
  content: "";
  position: absolute;
  top: 0; left: -60%;
  width: 50%; height: 100%;
  background: linear-gradient(120deg, transparent, rgba(255,255,255,.28), transparent);
  transform: skewX(-20deg);
  transition: left .6s var(--ease);
  pointer-events: none;
}
.btn-primary:hover::after { left: 120%; }
.btn-ghost {
  background: transparent;
  color: var(--text-1);
  border: 1px solid var(--line-strong);
  backdrop-filter: blur(8px);
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); box-shadow: var(--glow); }
.hero-stats {
  display: inline-flex;
  align-items: center;
  gap: 1.8rem;
  margin-top: 2.8rem;
  padding: 0.9rem 2.2rem;
  background: rgba(16, 21, 31, 0.7);
  border: 1px solid var(--line);
  border-radius: 18px;
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow);
}
.hero-stat { display: flex; flex-direction: column; align-items: center; gap: .1rem; }
.hero-stat-num {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  font-variant-numeric: tabular-nums;
}
.hero-stat-label { font-size: .76rem; color: var(--text-3); letter-spacing: .1em; }
.hero-stat-divider { width: 1px; height: 2.2rem; background: var(--line-strong); }

/* ========== 分类导航条 ========== */
.cat-strip {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0 1rem 2.5rem;
}
.cat-chip {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  padding: .42em 1.05em;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: .85rem;
  color: var(--text-2);
  transition: all .2s var(--ease);
}
.cat-chip:hover {
  color: #fff;
  background: var(--grad);
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: var(--glow);
}

/* ========== 区块标题 ========== */
.sec-head { margin-bottom: 2rem; }
.sec-label {
  font-family: var(--font-mono);
  font-size: .76rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .22em;
  font-weight: 700;
  margin-bottom: .5rem;
}
.sec-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-1);
}
.sec-desc { color: var(--text-3); margin-top: .4rem; }

/* ========== 文章卡片 ========== */
.post-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}
.post-card {
  display: flex;
  flex-direction: column;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s var(--ease);
  height: 100%;
}
.post-card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, rgba(110,168,255,.5), transparent 40%, transparent 60%, rgba(34,211,238,.4));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity .3s var(--ease);
  pointer-events: none;
  z-index: 2;
}
.post-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md), var(--glow);
  border-color: transparent;
}
.post-card:hover::before { opacity: 1; }
.post-thumb-wrap { position: relative; aspect-ratio: 21/9; overflow: hidden; background: var(--bg-3); }
.post-thumb { width: 100%; height: 100%; object-fit: cover; transition: transform .55s var(--ease); }
.post-card:hover .post-thumb { transform: scale(1.05); }
.post-cat {
  position: absolute;
  top: .8rem; left: .8rem;
  padding: .2em .8em;
  background: rgba(10, 14, 22, 0.75);
  border: 1px solid rgba(255,255,255,.14);
  color: #eaf2ff;
  border-radius: 999px;
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .04em;
  backdrop-filter: blur(10px);
  z-index: 3;
}
.post-grad-cover {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: .6rem;
  overflow: hidden;
}
.post-grad-cover::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 60% at 70% 15%, rgba(255,255,255,.22), transparent 55%),
    radial-gradient(ellipse 60% 55% at 15% 85%, rgba(255,255,255,.10), transparent 55%);
}
.post-grad-cover::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.06) 1px, transparent 1px);
  background-size: 26px 26px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 40%, black 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 40%, black 20%, transparent 75%);
}
.post-grad-cover > * { position: relative; z-index: 1; }
.post-grad-icon { display: inline-flex; filter: drop-shadow(0 4px 14px rgba(0,0,0,.35)); opacity: .95; }
.post-grad-icon svg { width: 26px; height: 26px; }
.post-grad-cat {
  font-size: .76rem;
  font-weight: 600;
  letter-spacing: .12em;
  color: rgba(255,255,255,.92);
  text-transform: uppercase;
  text-shadow: 0 1px 6px rgba(0,0,0,.3);
}
.post-body {
  padding: 1.25rem 1.25rem 1.4rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}
.post-title {
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.42;
  color: var(--text-1);
  margin-bottom: .6rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: color .2s var(--ease);
}
.post-card:hover .post-title { color: var(--accent); }
.post-excerpt {
  color: var(--text-3);
  font-size: .88rem;
  line-height: 1.65;
  margin-bottom: .9rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}
.post-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: .82rem;
  color: var(--text-3);
  padding-top: .8rem;
  border-top: 1px solid var(--line);
}
.post-meta span { display: inline-flex; align-items: center; gap: .35rem; }
.meta-icon { opacity: .75; flex-shrink: 0; }

/* ========== 查看全部 / 标签云 ========== */
.see-all { display: flex; justify-content: center; margin-top: 3rem; }
.tag-cloud { display: flex; flex-wrap: wrap; gap: .5rem; margin-top: 1.4rem; }
.tag-pill {
  padding: .4em 1.05em;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: .84rem;
  color: var(--text-2);
  transition: all .2s var(--ease);
}
.tag-pill:hover {
  color: #fff;
  background: var(--grad);
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: var(--glow);
}

/* ========== 文章详情 ========== */
.article-wrap { display: grid; grid-template-columns: 1fr 220px; gap: 2rem; align-items: start; }
.article {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  padding: clamp(1.4rem, 4vw, 3rem);
  box-shadow: var(--shadow);
  min-width: 0;
}
.back-link {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  color: var(--text-2);
  font-size: .9rem;
  margin-bottom: 1.4rem;
  transition: color var(--dur) var(--ease);
}
.back-link:hover { color: var(--accent); }
.article-cover {
  width: 100%;
  aspect-ratio: 16/7;
  object-fit: cover;
  border-radius: var(--radius-lg);
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}
.article-cover-grad {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: .9rem;
  position: relative;
  overflow: hidden;
  margin-bottom: 2rem;
}
.article-cover-grad::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 60% at 70% 15%, rgba(255,255,255,.22), transparent 55%),
    radial-gradient(ellipse 60% 55% at 15% 85%, rgba(255,255,255,.10), transparent 55%);
}
.article-cover-grad > * { position: relative; z-index: 1; }
.article-cover-grad .post-grad-icon svg { width: 64px; height: 64px; filter: drop-shadow(0 6px 20px rgba(0,0,0,.35)); }
.article-cat {
  display: inline-block;
  padding: .25em 1em;
  background: var(--grad-soft);
  color: var(--accent);
  border: 1px solid rgba(110,168,255,.25);
  border-radius: 999px;
  font-size: .8rem;
  font-weight: 600;
  margin-bottom: 1rem;
}
.article-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
  color: var(--text-1);
  margin-bottom: 1rem;
}
.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  color: var(--text-3);
  font-size: .86rem;
  margin-bottom: 1.8rem;
}
.article-meta span { display: inline-flex; align-items: center; gap: .4rem; }
.article-tags { display: inline-flex; gap: .4rem; flex-wrap: wrap; }
.article-tags a {
  font-size: .78rem;
  color: var(--text-3);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0 .7em;
  line-height: 1.8;
  transition: all .2s var(--ease);
}
.article-tags a:hover { color: var(--accent); border-color: var(--accent); }

/* 正文 */
.article-body { font-size: 1.05rem; line-height: 1.9; color: var(--text-1); }
.article-body > :first-child { margin-top: 0; }
.article-body > :last-child { margin-bottom: 0; }
.article-body p { margin: 0 0 1.25em; }
.article-body h2 {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin-top: 2.4em;
  padding-bottom: .45em;
  border-bottom: 1px solid var(--line);
  position: relative;
  scroll-margin-top: 4rem;
}
.article-body h2::before {
  content: "";
  position: absolute;
  left: -1rem;
  top: .22em;
  width: 4px;
  height: .9em;
  border-radius: 4px;
  background: var(--grad);
}
.article-body h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-top: 2em;
  letter-spacing: -0.01em;
  scroll-margin-top: 4rem;
}
.article-body strong { color: var(--text-1); font-weight: 700; }
.article-body a {
  color: var(--accent);
  font-weight: 600;
  word-break: break-word;
  border-bottom: 1px solid rgba(110,168,255,.3);
  transition: border-color var(--dur) var(--ease);
}
.article-body a:hover { border-color: var(--accent); }
.article-body blockquote {
  position: relative;
  background: var(--grad-soft);
  border-left: 3px solid var(--accent);
  border-radius: 0 12px 12px 0;
  padding: 1em 1.4em;
  margin: 1.6em 0;
  color: var(--text-2);
  font-style: italic;
}
.article-body blockquote::before {
  content: "“";
  position: absolute;
  left: .5rem;
  top: .1rem;
  font-size: 2rem;
  line-height: 1;
  color: var(--accent);
  opacity: .5;
}
.article-body ul, .article-body ol { margin: 1em 0 1.25em; padding-left: 1.5rem; }
.article-body ul li { list-style: disc; margin-bottom: .5em; }
.article-body ul li::marker { color: var(--accent); }
.article-body ol li { list-style: decimal; margin-bottom: .5em; }
.article-body img {
  border-radius: 14px;
  box-shadow: var(--shadow);
  margin: 1.8em auto;
}
.article-body pre {
  background: #0d1420;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.04), var(--shadow);
  padding: 1.3em 1.4em;
  overflow-x: auto;
  line-height: 1.65;
  font-size: .92em;
  margin: 1.6em 0;
}
.article-body code { font-family: var(--font-mono); font-size: .9em; }
.article-body :not(pre) > code {
  background: var(--grad-soft);
  color: var(--accent);
  padding: .15em .45em;
  border-radius: 6px;
  border: 1px solid rgba(110,168,255,.2);
}
.article-body pre code { background: none; padding: 0; }
.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.6em 0;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  font-size: .94rem;
}
.article-body th, .article-body td {
  border: 1px solid var(--line);
  padding: .6em .9em;
  text-align: left;
}
.article-body th { background: var(--bg-3); font-weight: 700; }
.article-body hr {
  border: none;
  height: 1px;
  background: var(--line-strong);
  margin: 2.5em auto;
  max-width: 60%;
}
.heading-anchor {
  color: var(--text-4);
  text-decoration: none;
  margin-left: .4rem;
  opacity: 0;
  transition: opacity .2s;
}
.article-body h2:hover .heading-anchor,
.article-body h3:hover .heading-anchor { opacity: 1; }

/* 目录 */
.toc {
  position: sticky;
  top: calc(var(--nav-h) + 1.5rem);
  max-height: calc(100vh - var(--nav-h) - 3rem);
  overflow-y: auto;
  border-left: 1px solid var(--line);
  padding-left: 1.1rem;
  font-size: .82rem;
  line-height: 1.7;
  color: var(--text-2);
}
.toc-title {
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: .8rem;
}
.toc ol { list-style: none; }
.toc li { margin: 0; }
.toc a {
  display: block;
  padding: .28rem 0 .28rem .6rem;
  color: var(--text-2);
  border-left: 2px solid transparent;
  margin-left: -1.1rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: color .15s var(--ease), border-color .15s var(--ease);
}
.toc a:hover { color: var(--accent); }
.toc .toc-h3 a { padding-left: 1.4rem; font-size: .76rem; }

/* 上一篇 / 下一篇 */
.prev-next {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2.5rem;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: 1.5rem;
}
.pn-item a {
  display: flex;
  flex-direction: column;
  gap: .4rem;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  transition: all .25s var(--ease);
}
.pn-item a:hover { border-color: var(--accent); box-shadow: var(--glow); transform: translateY(-2px); }
.pn-item-next { text-align: right; }
.pn-item .pn-label { font-size: .76rem; color: var(--text-3); letter-spacing: .1em; }
.pn-item .pn-title { font-size: .95rem; font-weight: 600; color: var(--text-1); line-height: 1.4; }

/* 相关阅读 */
.related { border-top: 1px solid var(--line); padding-block: 3.5rem; }
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 1.6rem;
}

/* 返回顶部 */
.back-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 1500;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-2);
  border: 1px solid var(--line-strong);
  color: var(--text-2);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: all .3s var(--ease);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
}
.back-top.show { opacity: 1; transform: translateY(0); pointer-events: auto; }
.back-top:hover { color: #fff; background: var(--grad); border-color: transparent; box-shadow: var(--glow); }

/* ========== 关于页 ========== */
.about-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; }
.about-card {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.25rem;
  transition: all .25s var(--ease);
}
.about-card:hover { border-color: var(--line-accent); transform: translateY(-3px); box-shadow: var(--shadow), var(--glow); }
.about-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: .5rem; color: var(--text-1); }
.about-card p { margin: 0; color: var(--text-2); font-size: .88rem; line-height: 1.65; }
.about-subtitle { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; margin: .4rem 0 .6rem; color: var(--text-1); }
.about-desc { color: var(--text-2); margin: 0 0 1.6rem; }
.project-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.1rem; }
.project-card {
  display: block;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all .25s var(--ease);
}
.project-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg), var(--glow); border-color: var(--line-accent); }
.project-top { height: 84px; position: relative; overflow: hidden; }
.project-top::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 60% at 75% 20%, rgba(255,255,255,.25), transparent 55%);
}
.project-body { padding: 1.2rem; }
.project-tag {
  display: inline-block;
  font-size: .68rem;
  padding: .2em .7em;
  border-radius: 999px;
  background: var(--bg-3);
  border: 1px solid var(--line);
  color: var(--text-2);
  font-weight: 600;
  letter-spacing: .06em;
  margin-bottom: .6rem;
}
.project-body h3 { font-size: 1.08rem; font-weight: 700; color: var(--text-1); margin: .4rem 0; line-height: 1.35; }
.project-body p { margin: 0; color: var(--text-2); font-size: .87rem; line-height: 1.6; }
.contact-box {
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  padding: 2.6rem 1.5rem;
  text-align: center;
  box-shadow: var(--shadow);
}
.contact-box > p:first-child { color: var(--text-2); margin: 0 0 1rem; }
.contact-link {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .55em 1.3em;
  background: var(--bg-3);
  border: 1px solid var(--line);
  border-radius: 100px;
  color: var(--text-1);
  font-size: .9rem;
  transition: all .2s var(--ease);
}
.contact-link:hover { border-color: var(--accent); color: var(--accent); box-shadow: var(--glow); }
.contact-note { color: var(--text-3); font-size: .8rem; margin: 1.5rem 0 0; }

/* ========== 搜索 ========== */
.search-input {
  width: 100%;
  background: var(--bg-2);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  padding: .95em 1.3em;
  color: var(--text-1);
  font-size: 1.05rem;
  outline: none;
  font-family: inherit;
  transition: border-color .2s var(--ease), box-shadow .2s var(--ease);
}
.search-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.search-meta { color: var(--text-3); font-size: .9rem; margin: 1rem 0; }
.search-results { display: grid; gap: .9rem; }
.search-item {
  display: block;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  transition: all .2s var(--ease);
}
.search-item:hover { border-color: var(--accent); transform: translateX(4px); box-shadow: var(--shadow), var(--glow); }
.search-item-head { display: flex; align-items: center; gap: .8rem; margin-bottom: .6rem; flex-wrap: wrap; }
.search-date { color: var(--text-3); font-size: .8rem; font-family: var(--font-mono); }
.search-tags { color: var(--text-3); font-size: .8rem; }
.search-item-title { font-size: 1.15rem; font-weight: 700; line-height: 1.4; color: var(--text-1); margin: 0 0 .4rem; }
.search-item-desc { color: var(--text-2); font-size: .93rem; line-height: 1.6; margin: 0; }
.search-empty { background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius); padding: 2rem; text-align: center; color: var(--text-3); }
mark { background: var(--accent-soft); color: var(--accent); padding: 0 .15em; border-radius: 2px; }

/* ========== 404 ========== */
.notfound-code {
  font-size: clamp(5rem, 12vw, 8rem);
  font-weight: 800;
  line-height: 1;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  filter: drop-shadow(0 8px 30px rgba(110,168,255,.35));
}

/* ========== 搜索浮层 ========== */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: 1200;
  background: rgba(5, 7, 13, 0.6);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  display: none;
  align-items: flex-start;
  justify-content: center;
  padding: 12vh 1.5rem 0;
}
.search-overlay.open { display: flex; }
.search-box {
  width: 100%;
  max-width: 560px;
  background: var(--bg-2);
  border: 1px solid var(--line-strong);
  border-radius: 18px;
  box-shadow: var(--shadow-lg), var(--glow);
  padding: .5rem;
}
.search-box input {
  width: 100%;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-1);
  font-size: 1.1rem;
  padding: .7em 1em;
  font-family: inherit;
}

/* ========== 页脚 ========== */
.footer {
  position: relative;
  background: #05080f;
  border-top: 1px solid var(--line);
  margin-top: 3rem;
}
.footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(110,168,255,.5), rgba(34,211,238,.5), transparent);
}
.footer-inner {
  max-width: var(--max-w);
  margin-inline: auto;
  padding: 3rem 1.5rem 2rem;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem;
}
.footer h4 { color: var(--text-1); font-size: 1rem; font-weight: 700; letter-spacing: .06em; margin-bottom: .9rem; }
.footer p { color: var(--text-3); font-size: .88rem; line-height: 1.7; }
.footer-links { display: flex; flex-direction: column; gap: .5rem; }
.footer-links a { color: var(--text-2); font-size: .88rem; transition: color .2s, padding-left .2s var(--ease); }
.footer-links a:hover { color: var(--accent); padding-left: 4px; }
.footer-bottom {
  max-width: var(--max-w);
  margin-inline: auto;
  padding: 1.2rem 1.5rem 1.6rem;
  border-top: 1px solid var(--line);
  color: var(--text-3);
  font-size: .82rem;
  text-align: center;
}
.footer-bottom a { color: var(--text-2); }
.footer-bottom a:hover { color: var(--accent); }

/* ========== 滚动条 ========== */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg-1); }
::-webkit-scrollbar-thumb { background: var(--bg-3); border-radius: 5px; border: 2px solid var(--bg-1); }
::-webkit-scrollbar-thumb:hover { background: linear-gradient(180deg, var(--accent), var(--accent-2)); }

/* ========== 动画 ========== */
.fade-up { opacity: 0; transform: translateY(20px); transition: opacity .6s var(--ease-out), transform .6s var(--ease-out); }
.fade-up.in { opacity: 1; transform: none; }

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
  .article-wrap { grid-template-columns: 1fr; }
  .toc { display: none; }
}
@media (max-width: 768px) {
  .nav-menu { display: none; }
  .nav-toggle { display: inline-flex !important; }
  .hero { padding-top: calc(var(--nav-h) + 3rem); }
  .hero h1 { font-size: 2.3rem; }
  .hero-stats { gap: 1rem; padding: .7rem 1.4rem; }
  .hero-stat-num { font-size: 1.2rem; }
  .post-grid { grid-template-columns: 1fr; }
  .prev-next { grid-template-columns: 1fr; }
  .pn-item-next { text-align: left; }
  .footer-inner { grid-template-columns: 1fr; gap: 1.8rem; }
  .back-top { right: 1rem; bottom: 1rem; width: 40px; height: 40px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 移动端抽屉菜单 */
.nav-drawer { display: none; }
.nav-drawer.open {
  display: block;
  border-top: 1px solid var(--line);
  background: var(--bg-1);
  padding: .6rem 1.5rem 1rem;
}
.nav-drawer a {
  display: flex;
  align-items: center;
  gap: .5rem;
  padding: .7rem .6rem;
  border-radius: 8px;
  color: var(--text-2);
  font-size: 1rem;
  font-weight: 500;
}
.nav-drawer a:hover, .nav-drawer a.active { color: var(--text-1); background: var(--bg-3); }