/* Sirius-QQ-Bot 官网 · ToDesk 风格科技蓝 · 深色 Hero + 浅色内容区 */
:root {
  --blue: #2e6bff;
  --blue-2: #5b93ff;
  --cyan: #38bdf8;
  --navy-1: #050d1f;
  --navy-2: #0a1c40;
  --bg: #ffffff;
  --bg-soft: #f2f6ff;
  --panel: #ffffff;
  --line: rgba(13, 42, 96, .1);
  --line-2: rgba(13, 42, 96, .18);
  --tx: #0f1f45;
  --tx2: #49597b;
  --tx3: #7e8cab;
  --blue-soft: rgba(46, 107, 255, .08);
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --r: 14px;
  --ease: cubic-bezier(.22, .8, .3, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--tx);
  font-family: var(--sans);
  font-size: 15.5px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
::selection { background: rgba(46, 107, 255, .22); }

.wrap { max-width: 1180px; margin: 0 auto; padding: 0 28px; }
.wrap-narrow { max-width: 860px; }

a { color: inherit; text-decoration: none; }
h1, h2, h3 { font-family: var(--sans); font-weight: 700; letter-spacing: -.01em; }

/* ---------- 滚动显现动画 ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: .08s; }
.reveal.d2 { transition-delay: .18s; }
.reveal.d3 { transition-delay: .3s; }
.reveal.d4 { transition-delay: .42s; }
.stagger .reveal:nth-child(2) { transition-delay: .08s; }
.stagger .reveal:nth-child(3) { transition-delay: .16s; }
.stagger .reveal:nth-child(4) { transition-delay: .24s; }
.stagger .reveal:nth-child(5) { transition-delay: .32s; }
.stagger .reveal:nth-child(6) { transition-delay: .4s; }

/* ---------- 顶部导航（深色） ---------- */
.site-head {
  position: sticky; top: 0; z-index: 50;
  background: rgba(5, 13, 31, .78);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color .4s, background .4s;
}
.site-head.scrolled { border-bottom-color: rgba(148, 163, 184, .14); background: rgba(5, 13, 31, .92); }
.head-in { display: flex; align-items: center; gap: 34px; height: 62px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--blue-2); }
.brand-mk { width: 24px; height: 24px; transition: transform .6s var(--ease); }
.brand:hover .brand-mk { transform: rotate(72deg); }
.brand-tx { font-size: 17.5px; font-weight: 700; letter-spacing: .02em; color: #f2f6ff; }
.brand-tx em { font-style: normal; color: var(--blue-2); }
.site-nav { display: flex; gap: 26px; margin-left: auto; }
.head-actions { display: flex; align-items: center; gap: 10px; }
.site-nav a { font-size: 13.5px; color: #a3b2d4; transition: color .25s; position: relative; }
.site-nav a::after { content: ""; position: absolute; left: 0; right: 0; bottom: -6px; height: 1.5px; background: var(--blue-2); transform: scaleX(0); transition: transform .35s var(--ease); transform-origin: left; }
.site-nav a:hover { color: #fff; }
.site-nav a:hover::after { transform: scaleX(1); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 26px; border-radius: 11px; font-size: 14px; font-weight: 600;
  border: 1px solid transparent; cursor: pointer; transition: transform .3s var(--ease), box-shadow .3s, background .3s, border-color .3s;
  /* button 元素 UA 默认样式重置（白底/字体不继承），a 标签无此问题 */
  background: transparent; font-family: inherit; line-height: inherit; text-decoration: none;
}
.btn:active { transform: scale(.97); }
.btn-sm { padding: 7px 16px; font-size: 13px; }
.btn-blue { background: linear-gradient(135deg, #3d7bff, #1d4ed8); color: #fff; box-shadow: 0 6px 22px rgba(46, 107, 255, .38); }
.btn-blue:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(46, 107, 255, .5); }
.btn-white { background: #fff; color: #1d4ed8; box-shadow: 0 8px 24px rgba(4, 17, 46, .25); }
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 14px 34px rgba(4, 17, 46, .34); }
.btn-line { border-color: rgba(255, 255, 255, .3); color: #fff; }
.btn-line:hover { border-color: var(--blue-2); color: var(--blue-2); transform: translateY(-2px); }

/* ---------- Hero（深海军蓝） ---------- */
.hero {
  position: relative; overflow: hidden;
  background: radial-gradient(1100px 560px at 78% -10%, #0c2a66 0%, var(--navy-1) 62%);
  color: #eaf0fa;
}
.hero::before {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background:
    linear-gradient(rgba(91, 147, 255, .05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(91, 147, 255, .05) 1px, transparent 1px);
  background-size: 44px 44px;
  -webkit-mask-image: radial-gradient(70% 62% at 60% 28%, #000 30%, transparent 76%);
  mask-image: radial-gradient(70% 62% at 60% 28%, #000 30%, transparent 76%);
}
#starfield { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }
.hero-orb { position: absolute; border-radius: 50%; filter: blur(90px); pointer-events: none; }
.orb-a { width: 460px; height: 460px; background: rgba(46, 107, 255, .22); top: -140px; left: -90px; animation: orbFloat 11s ease-in-out infinite alternate; }
.orb-b { width: 380px; height: 380px; background: rgba(56, 189, 248, .13); bottom: -150px; right: -60px; animation: orbFloat 13s ease-in-out infinite alternate-reverse; }
@keyframes orbFloat { from { transform: translate(0, 0) } to { transform: translate(40px, 30px) } }

.hero-in {
  position: relative; z-index: 2;
  display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center;
  padding-top: 84px; padding-bottom: 92px;
}
.eyebrow {
  display: inline-block; font-size: 12px; letter-spacing: .22em; color: #8fb4ff;
  border: 1px solid rgba(91, 147, 255, .4); background: rgba(46, 107, 255, .14);
  padding: 5px 14px; border-radius: 99px; margin-bottom: 20px;
}
.hero h1 {
  font-size: clamp(42px, 5.4vw, 64px); line-height: 1.1; font-weight: 800; letter-spacing: -.015em;
  background: linear-gradient(120deg, #ffffff 30%, #b9cdfd 70%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(120deg, #6ea8ff, #2e6bff);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lede { margin-top: 18px; font-size: 16.5px; color: #a3b2d4; max-width: 520px; }
.hero-cta { display: flex; gap: 14px; margin-top: 30px; flex-wrap: wrap; }

.hero-term {
  background: rgba(6, 13, 30, .88); border: 1px solid rgba(91, 147, 255, .25); border-radius: 16px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, .5), 0 0 0 1px rgba(46, 107, 255, .06);
  overflow: hidden; backdrop-filter: blur(8px);
  transform: perspective(1200px) rotateY(-4deg) rotateX(2deg);
  transition: transform .8s var(--ease);
}
.hero-term:hover { transform: perspective(1200px) rotateY(0) rotateX(0); }
.term-bar { display: flex; align-items: center; gap: 7px; padding: 11px 15px; border-bottom: 1px solid rgba(148, 163, 184, .12); }
.term-bar i { width: 10px; height: 10px; border-radius: 50%; background: #25355c; }
.term-bar i:first-child { background: #e0574f; }
.term-bar i:nth-child(2) { background: #e2a63d; }
.term-bar i:nth-child(3) { background: #34d399; }
.term-bar span { margin-left: 8px; font-size: 11.5px; color: #71829f; font-family: var(--mono); }
.term-body { padding: 18px 20px 20px; font-family: var(--mono); font-size: 12.8px; line-height: 2.05; min-height: 208px; white-space: pre-wrap; color: #c4d2ef; }
.c-p { color: #7dd3fc; }
.c-ok { color: #8fb4ff; }
.c-go { color: #34d399; }
.c-dim { color: #64748b; }
.caret { display: inline-block; width: 8px; height: 15px; background: #6ea8ff; vertical-align: -2px; animation: blink 1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0 } }

.hero-scroll {
  position: absolute; left: 50%; bottom: 24px; transform: translateX(-50%); z-index: 3;
  width: 26px; height: 42px; border: 1.5px solid rgba(255, 255, 255, .28); border-radius: 14px;
  display: flex; justify-content: center; padding-top: 8px; transition: border-color .3s;
}
.hero-scroll span { width: 3px; height: 8px; border-radius: 2px; background: #6ea8ff; animation: scrollHint 1.8s ease-in-out infinite; }
.hero-scroll:hover { border-color: var(--blue-2); }
@keyframes scrollHint { 0% { transform: translateY(0); opacity: 1 } 70% { transform: translateY(12px); opacity: 0 } 100% { transform: translateY(0); opacity: 0 } }

/* ---------- 数据统计带（ToDesk 风格蓝色横幅） ---------- */
.stats-band {
  position: relative; overflow: hidden;
  background: linear-gradient(120deg, #1743c0 0%, #2e6bff 55%, #38bdf8 100%);
}
.stats-band::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(600px 200px at 85% 50%, rgba(255, 255, 255, .14), transparent 70%);
}
.stats-list { position: relative; z-index: 2; display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; list-style: none; padding: 28px 0; }
.stats-list b { display: block; font-size: clamp(26px, 3vw, 36px); font-weight: 800; color: #fff; letter-spacing: -.01em; font-variant-numeric: tabular-nums; }
.stats-list span { font-size: 12.5px; color: rgba(255, 255, 255, .78); }

/* ---------- 区块通用 ---------- */
.sec { padding: 64px 0; position: relative; }
.sec-alt { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.sec-dark {
  --panel: #0d1f47;
  --panel-2: #13295c;
  --line: rgba(148, 163, 184, .14);
  --line-2: rgba(148, 163, 184, .26);
  --tx: #eef3ff;
  --tx2: #a3b2d4;
  --tx3: #71829f;
  background: linear-gradient(180deg, var(--navy-2) 0%, var(--navy-1) 100%);
  color: var(--tx);
}
.sec-h { max-width: 660px; margin-bottom: 32px; }
.kicker { font-size: 12px; letter-spacing: .24em; color: var(--blue); margin-bottom: 10px; font-weight: 600; }
.sec-dark .kicker { color: var(--blue-2); }
.sec-h h2 { font-size: clamp(26px, 3.1vw, 34px); font-weight: 800; }
.sec-h p { margin-top: 10px; color: var(--tx2); font-size: 14.5px; }

.grid { display: grid; gap: 16px; }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--r);
  padding: 22px 24px; position: relative;
}
.lift { transition: transform .35s var(--ease), box-shadow .35s, border-color .35s; }
.lift:hover { transform: translateY(-4px); border-color: rgba(46, 107, 255, .4); box-shadow: 0 18px 44px rgba(15, 32, 69, .12); }
.sec-dark .lift:hover { box-shadow: 0 18px 44px rgba(2, 8, 23, .5); border-color: rgba(91, 147, 255, .45); }
.card h3 { font-size: 17px; margin-bottom: 8px; }
.card p { font-size: 13.8px; color: var(--tx2); }
.card-ico {
  width: 42px; height: 42px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: var(--blue-soft); border: 1px solid rgba(46, 107, 255, .22); font-size: 19px; margin-bottom: 14px;
  transition: transform .4s var(--ease), box-shadow .4s;
}
.lift:hover .card-ico { transform: scale(1.08) rotate(-4deg); box-shadow: 0 0 22px rgba(46, 107, 255, .3); }

/* ---------- 在线体验 ---------- */
.sec-demo { background: radial-gradient(900px 400px at 50% 0%, rgba(46, 107, 255, .05), transparent 65%); }
.demo-tabs { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin-bottom: 16px; max-width: 640px; }
.demo-tab {
  text-align: left; padding: 14px 18px; border-radius: 12px; cursor: pointer;
  background: var(--panel); border: 1px solid var(--line); color: var(--tx2);
  transition: border-color .3s, background .3s, transform .3s var(--ease), box-shadow .3s;
}
.demo-tab b { display: block; font-size: 14.5px; color: var(--tx); font-weight: 600; }
.demo-tab span { font-size: 11.5px; color: var(--tx3); }
.demo-tab:hover { transform: translateY(-2px); border-color: var(--line-2); }
.demo-tab.on {
  border-color: rgba(46, 107, 255, .5); background: linear-gradient(160deg, rgba(46, 107, 255, .1), var(--panel));
  box-shadow: 0 8px 26px rgba(46, 107, 255, .14);
}
.demo-tab.on b { color: var(--blue); }

.demo-frame {
  border: 1px solid rgba(13, 42, 96, .2); border-radius: 16px; overflow: hidden;
  background: var(--navy-1); box-shadow: 0 30px 80px rgba(15, 32, 69, .22);
}
.df-bar { display: flex; align-items: center; gap: 14px; padding: 10px 16px; border-bottom: 1px solid rgba(148, 163, 184, .12); background: rgba(6, 13, 30, .9); }
.df-dots { display: flex; gap: 6px; }
.df-dots i { width: 9px; height: 9px; border-radius: 50%; background: #25355c; }
.df-dots i:first-child { background: #e0574f; }
.df-dots i:nth-child(2) { background: #e2a63d; }
.df-dots i:nth-child(3) { background: #34d399; }
.df-url {
  flex: 1; max-width: 420px; font-size: 11.5px; color: #71829f; font-family: var(--mono);
  background: rgba(148, 163, 184, .08); border: 1px solid rgba(148, 163, 184, .14); border-radius: 8px; padding: 4px 12px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.df-chip {
  margin-left: auto; font-size: 11px; color: #8fb4ff; white-space: nowrap;
  border: 1px solid rgba(91, 147, 255, .35); background: rgba(46, 107, 255, .12); border-radius: 99px; padding: 3px 12px;
}
.df-stage { position: relative; height: min(76vh, 780px); background: #0b111f; }
.df-stage iframe {
  position: absolute; inset: 0; width: 100%; height: 100%; border: 0;
  opacity: 0; transition: opacity .5s var(--ease); pointer-events: none;
}
.df-stage iframe.on { opacity: 1; pointer-events: auto; }
.df-loading {
  position: absolute; inset: 0; display: flex; flex-direction: column; gap: 14px;
  align-items: center; justify-content: center; color: #71829f; font-size: 13px;
}
.df-spin {
  width: 30px; height: 30px; border-radius: 50%;
  border: 2.5px solid rgba(148, 163, 184, .25); border-top-color: var(--blue-2);
  animation: spin 1s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg) } }
.demo-note { margin-top: 12px; font-size: 12.5px; color: var(--tx3); }

/* ---------- 私有化部署带 ---------- */
.priv-note { margin-top: 18px; font-size: 13px; color: var(--tx3); }
.sec-priv .card h3 { color: var(--blue-2); }

/* ---------- 架构 ---------- */
.arch-platform { margin-bottom: 16px; }
.arch-platform h3 { color: var(--blue-2); }

.arch { padding: 28px 22px 20px; margin-bottom: 16px; overflow-x: auto; }
.arch-svg { width: 100%; min-width: 880px; height: auto; display: block; }
.arch-svg .node rect { fill: var(--panel-2); stroke: var(--line-2); stroke-width: 1; }
.arch-svg .node.hot rect { fill: rgba(46, 107, 255, .14); stroke: rgba(91, 147, 255, .55); }
.arch-svg .node.cloud rect { fill: rgba(56, 189, 248, .1); stroke: rgba(56, 189, 248, .45); }
.arch-svg .node.dim rect { fill: transparent; stroke-dasharray: 5 4; }
.arch-svg .nt { fill: var(--tx); font-size: 14.5px; font-weight: 600; font-family: var(--sans); }
.arch-svg .ns { fill: var(--tx3); font-size: 11px; font-family: var(--sans); }
.arch-svg .lk { stroke: #5b6b86; stroke-width: 1.4; }
.arch-svg .lk.dash { stroke-dasharray: 6 5; }
.arch-svg .lk.flow { stroke-dasharray: 7 6; animation: march 1.6s linear infinite; }
@keyframes march { to { stroke-dashoffset: -13 } }
.arch-svg .cap { fill: var(--tx3); font-size: 10.5px; font-family: var(--sans); }
.arch-note { margin-top: 16px; }

/* ---------- 步骤 ---------- */
.steps { list-style: none; display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.steps li { display: flex; gap: 18px; align-items: flex-start; }
.step-n {
  flex: none; font-size: 15px; font-weight: 800; color: var(--blue);
  width: 44px; height: 44px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: var(--blue-soft); border: 1px solid rgba(46, 107, 255, .25);
}

/* ---------- CTA 横幅（蓝色渐变） ---------- */
.cta-band {
  margin-top: 26px; display: flex; align-items: center; justify-content: space-between; gap: 22px;
  background: linear-gradient(120deg, #1743c0 0%, #2e6bff 60%, #38bdf8 100%);
  border: none; border-radius: var(--r); padding: 26px 30px;
  box-shadow: 0 20px 50px rgba(29, 78, 216, .3);
  flex-wrap: wrap;
}
.cta-band h3 { font-size: 19px; color: #fff; }
.cta-band p { margin-top: 4px; color: rgba(255, 255, 255, .82); font-size: 13.8px; }

/* ---------- FAQ ---------- */
.faq-list { display: grid; grid-template-columns: 1fr 1fr; gap: 14px 20px; align-items: start; }
@media (max-width: 860px) { .faq-list { grid-template-columns: 1fr; } }
.faq-list details { padding: 0; overflow: hidden; }
.faq-list summary {
  cursor: pointer; list-style: none; padding: 16px 22px; font-weight: 600; font-size: 15px;
  display: flex; align-items: center; justify-content: space-between; transition: color .25s;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; font-size: 19px; font-weight: 400; color: var(--blue); transition: transform .3s var(--ease); }
.faq-list details[open] summary::after { transform: rotate(45deg); }
.faq-list summary:hover { color: var(--blue); }
.faq-list details p { padding: 0 22px 16px; font-size: 14px; color: var(--tx2); }

/* ---------- 页脚（深海军蓝） ---------- */
.site-foot { background: #04102b; color: #a3b2d4; padding: 40px 0 26px; }
.foot-in { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.foot-brand { display: flex; align-items: center; gap: 12px; color: var(--blue-2); }
.foot-name { font-size: 16.5px; font-weight: 700; color: #f2f6ff; }
.foot-slogan { font-size: 12px; color: #71829f; margin-top: 2px; }
.foot-nav { display: flex; gap: 22px; }
.foot-nav a { font-size: 13px; color: #93a5c8; transition: color .25s; }
.foot-nav a:hover { color: #fff; }
.foot-copy {
  margin-top: 24px; padding-top: 18px; border-top: 1px solid rgba(148, 163, 184, .12);
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  font-size: 12.5px; color: #71829f;
}

/* ---------- 页脚协议链接 ---------- */
.foot-legal a, .foot-mail a { color: #93a5c8; transition: color .25s; }
.foot-legal a:hover, .foot-mail a:hover { color: #fff; }
.foot-legal i { font-style: normal; margin: 0 10px; color: #3d4f74; }

/* ---------- 页脚备案信息 ---------- */
.foot-beian {
  flex-basis: 100%; display: flex; justify-content: center; align-items: center;
  gap: 10px; margin-top: 8px; font-size: 12.5px;
}
.foot-beian a { color: #71829f; transition: color .25s; display: inline-flex; align-items: center; gap: 5px; }
.foot-beian a:hover { color: #fff; }
.foot-beian i { font-style: normal; color: #3d4f74; }
.foot-beian svg { width: 14px; height: 14px; flex: none; }

/* ---------- 协议页（用户协议 / 隐私政策） ---------- */
.legal-hero {
  background: radial-gradient(900px 420px at 70% -20%, #0c2a66 0%, var(--navy-1) 62%);
  color: #eaf0fa; padding: 68px 0 46px;
}
.legal-hero .kicker { color: var(--blue-2); }
.legal-hero h1 { font-size: clamp(28px, 3.6vw, 40px); font-weight: 800; letter-spacing: -.01em; }
.legal-meta {
  display: inline-block; margin-top: 16px; font-size: 12.5px; letter-spacing: .08em; color: #8fb4ff;
  border: 1px solid rgba(91, 147, 255, .4); background: rgba(46, 107, 255, .14);
  padding: 5px 14px; border-radius: 99px;
}
.legal-body { padding: 44px 0 64px; }
.legal-doc { max-width: 860px; margin: 0 auto; }
.legal-lede {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--r);
  padding: 20px 24px; font-size: 14.5px; color: var(--tx2); margin-bottom: 8px;
}
.legal-doc h2 {
  font-size: 18px; font-weight: 700; margin: 30px 0 10px;
  padding-left: 12px; border-left: 3px solid var(--blue);
}
.legal-doc p { margin: 7px 0; font-size: 14.5px; color: var(--tx2); }
.legal-doc p.legal-sub { padding-left: 18px; }
.legal-foot-note { margin-top: 36px; font-size: 12.5px; color: var(--tx3); }
.legal-foot-note a { color: var(--blue); }
.legal-foot-note a:hover { text-decoration: underline; }

/* ---------- 响应式 ---------- */
@media (max-width: 1020px) {
  .demo-tabs { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 960px) {
  .hero-in { grid-template-columns: 1fr; gap: 44px; padding-top: 68px; padding-bottom: 80px; }
  .hero-term { transform: none; }
  .g4, .g3 { grid-template-columns: repeat(2, 1fr); }
  .site-nav { display: none; }
  .df-stage { height: 66vh; }
}
@media (max-width: 640px) {
  .g4, .g3, .g2, .steps { grid-template-columns: 1fr; }
  .demo-tabs { grid-template-columns: 1fr; }
  .sec { padding: 48px 0; }
  .hero-cta { flex-wrap: wrap; }
  .head-in { gap: 18px; }
  .df-chip { display: none; }
  .df-stage { height: 60vh; }
  .stats-list { grid-template-columns: repeat(2, 1fr); gap: 18px 12px; padding: 22px 0; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
}

/* ---------- 单演示标签 ---------- */
.demo-tabs-single { grid-template-columns: 1fr; max-width: 320px; }

/* ---------- 深色 CTA 上的描边白按钮（底部深蓝横幅用） ---------- */
.btn-ghost-w { border: 1px solid rgba(255, 255, 255, .4); color: #fff; background: transparent; cursor: pointer; }
.btn-ghost-w:hover { border-color: #fff; transform: translateY(-2px); background: rgba(255, 255, 255, .08); }

/* ---------- Linux 一键部署弹层 ---------- */
.dk-mask {
  position: fixed; inset: 0; z-index: 2000;
  background: rgba(5, 13, 31, .62);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  display: flex; align-items: center; justify-content: center;
  padding: 22px;
  opacity: 0; transition: opacity .28s var(--ease);
}
/* 类选择器会压过 hidden 的 UA 样式导致透明遮罩常驻拦截点击，显式补回 */
.dk-mask[hidden] { display: none; }
.dk-mask.on { opacity: 1; }
.dk-card {
  width: 720px; max-width: 100%; max-height: calc(100vh - 44px);
  display: flex; flex-direction: column;
  background: linear-gradient(165deg, #0d1f47, #081430 70%);
  border: 1px solid rgba(91, 147, 255, .28);
  border-radius: 18px;
  box-shadow: 0 34px 90px rgba(2, 8, 26, .6), 0 0 0 1px rgba(255, 255, 255, .04) inset;
  color: #dbe6ff;
  overflow: hidden;
  transform: translateY(16px) scale(.97);
  transition: transform .32s var(--ease);
}
.dk-mask.on .dk-card { transform: none; }
.dk-head {
  display: flex; align-items: flex-start; gap: 14px;
  padding: 22px 24px 16px;
  border-bottom: 1px solid rgba(91, 147, 255, .16);
  background: linear-gradient(90deg, rgba(46, 107, 255, .14), transparent 60%);
}
.dk-head-txt { flex: 1; }
.dk-title { font-size: 19px; font-weight: 700; color: #fff; letter-spacing: .02em; }
.dk-sub { font-size: 13px; color: #8ea3d0; margin-top: 3px; }
.dk-close {
  width: 32px; height: 32px; border-radius: 9px; flex-shrink: 0;
  border: 1px solid rgba(91, 147, 255, .25); background: rgba(255, 255, 255, .04);
  color: #9db2dd; font-size: 13px; cursor: pointer;
  transition: background .2s, color .2s, border-color .2s;
}
.dk-close:hover { background: rgba(255, 255, 255, .1); color: #fff; border-color: rgba(91, 147, 255, .5); }
.dk-tabs {
  display: grid; grid-template-columns: 1fr 1fr; gap: 8px;
  padding: 12px 24px 0;
}
.dk-tab {
  padding: 8px 12px; border-radius: 10px;
  border: 1px solid rgba(91, 147, 255, .22);
  background: rgba(255, 255, 255, .03);
  color: #9db2dd; font-size: 13px; font-weight: 600; cursor: pointer;
  transition: background .2s, color .2s, border-color .2s;
}
.dk-tab:hover { color: #fff; border-color: rgba(91, 147, 255, .4); }
.dk-tab.on {
  background: rgba(46, 107, 255, .22);
  border-color: rgba(91, 147, 255, .55);
  color: #fff;
  box-shadow: 0 0 0 1px rgba(46, 107, 255, .18) inset;
}
.dk-body { padding: 16px 24px 24px; overflow-y: auto; }
.dk-pane[hidden] { display: none; }
.dk-step { margin-bottom: 18px; }
.dk-step:last-of-type { margin-bottom: 0; }
.dk-step-h { display: flex; align-items: center; gap: 9px; margin-bottom: 9px; font-size: 14px; }
.dk-step-h b { color: #fff; font-weight: 600; }
.dk-no {
  width: 21px; height: 21px; border-radius: 7px; flex-shrink: 0;
  display: grid; place-items: center;
  background: linear-gradient(135deg, #3d7bff, #1d4ed8);
  color: #fff; font-size: 12px; font-weight: 700;
  box-shadow: 0 3px 10px rgba(46, 107, 255, .4);
}
.dk-tip { font-size: 12px; color: #7c90bd; margin-left: 2px; }
.dk-cmd {
  display: flex; align-items: stretch; gap: 8px;
  background: #050d1f;
  border: 1px solid rgba(91, 147, 255, .22);
  border-radius: 11px;
  padding: 11px 12px 11px 15px;
}
.dk-cmd code {
  flex: 1; font-family: var(--mono); font-size: 12.8px; line-height: 1.7;
  color: #7ee8c7; word-break: break-all; align-self: center;
  text-shadow: 0 0 14px rgba(126, 232, 199, .18);
}
.dk-copy {
  flex-shrink: 0; align-self: center;
  padding: 6px 15px; border-radius: 8px;
  border: 1px solid rgba(46, 107, 255, .55);
  background: rgba(46, 107, 255, .16); color: #b9ccff;
  font-size: 12.5px; font-weight: 600; cursor: pointer;
  transition: background .2s, color .2s, border-color .2s, transform .15s;
}
.dk-copy:hover { background: rgba(46, 107, 255, .34); color: #fff; }
.dk-copy:active { transform: scale(.95); }
.dk-copy.ok { border-color: rgba(52, 211, 153, .6); background: rgba(52, 211, 153, .15); color: #6ee7b7; }
.dk-plain { font-size: 13.5px; color: #a9bce4; line-height: 1.8; }
.dk-inline {
  font-family: var(--mono); font-size: 12.3px; color: #8fd3ff;
  background: rgba(56, 189, 248, .1); border: 1px solid rgba(56, 189, 248, .22);
  border-radius: 6px; padding: 1.5px 7px;
}
.dk-alt {
  margin-top: 20px; padding: 13px 16px;
  border: 1px dashed rgba(91, 147, 255, .3); border-radius: 11px;
  background: rgba(46, 107, 255, .06);
  font-size: 13px; color: #93a7d4; line-height: 1.8;
}
.dk-alt b { color: #c9d8ff; }
.dk-alt a { color: #7fb0ff; text-decoration: none; border-bottom: 1px dashed rgba(127, 176, 255, .5); }
.dk-alt a:hover { color: #fff; border-bottom-color: #fff; }
@media (max-width: 640px) {
  .dk-head { padding: 18px 18px 14px; }
  .dk-body { padding: 16px 18px 20px; }
  .dk-cmd { flex-direction: column; }
  .dk-copy { align-self: flex-end; }
}