/* =============================================================================
   ShortCut 官网 · 设计系统 v2（质感升级）
   -----------------------------------------------------------------------------
   设计原则（"贵"的来源）：
     1. 光：不要纯色块 —— 每层表面都有渐变、内高光和接触/环境双层投影
     2. 克制：橙色只用于强调（≤5% 面积），金色/紫色只做深度衬托
     3. 呼吸：大留白（110px+）、字号强对比、负字距
     4. 细节：发丝级边框（rgba .06）、噪点质感、章节编号
     5. 动效：有意图、有节奏、可关闭（prefers-reduced-motion）
   零外部依赖（字体用系统栈）。
   ========================================================================== */

/* ── 1. 设计令牌 ────────────────────────────────────────────────────────── */
:root {
  /* ══ B 方案：中性极简 + 单点橙 ══
     规则：所有表面与文字都是中性灰阶，橙色只出现在
     主按钮 / 当前导航项 / 焦点环 / 少量强调，面积 < 2% */

  /* 表面层次 */
  --bg: #0a0a0b;
  --bg-soft: #0e0e10;
  --panel: #131315;
  --panel-2: #171719;
  --panel-3: #1c1c1f;

  /* 发丝边框 */
  --line: rgba(255, 255, 255, .075);
  --line-strong: rgba(255, 255, 255, .13);
  --line-soft: rgba(255, 255, 255, .05);

  /* 文本 */
  --text: #f4f4f5;
  --text-dim: #c8c8cb;
  --muted: #8e8e94;
  --muted-2: #66666c;

  /* 唯一彩色 */
  --accent: #ff6b1a;
  --accent-hi: #ff8642;
  --accent-lo: #d4540f;
  --accent-soft: rgba(255, 107, 26, .09);
  --accent-line: rgba(255, 107, 26, .28);

  /* 语义色（仅状态提示，不做装饰） */
  --good: #3dd68c;
  --warn: #ffb454;

  /* 形状 */
  --radius-xs: 8px;
  --radius-sm: 11px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-pill: 999px;

  /* 阴影（中性） */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, .34);
  --shadow-sm: 0 2px 6px rgba(0, 0, 0, .32), 0 8px 22px rgba(0, 0, 0, .26);
  --shadow: 0 4px 12px rgba(0, 0, 0, .34), 0 18px 50px rgba(0, 0, 0, .36);
  --shadow-lg: 0 8px 22px rgba(0, 0, 0, .36), 0 34px 80px rgba(0, 0, 0, .42);
  --shadow-accent: 0 4px 14px rgba(255, 107, 26, .2), 0 14px 36px rgba(255, 107, 26, .16);
  --inset-hi: inset 0 1px 0 rgba(255, 255, 255, .07);

  /* 排版 */
  --font: "Segoe UI Variable Display", "Segoe UI", "Microsoft YaHei UI", "PingFang SC",
          system-ui, -apple-system, sans-serif;
  --font-mono: "Cascadia Code", "Cascadia Mono", Consolas, "SF Mono", monospace;

  /* 布局 */
  --maxw: 1200px;
  --gap: 26px;
  --nav-h: 68px;

  /* 缓动 */
  --ease: cubic-bezier(.22, 1, .36, 1);
  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --ease-spring: cubic-bezier(.34, 1.56, .64, 1);

  /* 噪点 */
  --noise: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)'/%3E%3C/svg%3E");

  color-scheme: dark;
}

/* ══ 亮色模式（黑白切换）═════════════════════════════════════════════════
   中性纸感白，同一套橙色只调深一档以保证对比度 */
html[data-mode="light"] {
  --bg: #f6f5f3;
  --bg-soft: #fbfaf9;
  --panel: #ffffff;
  --panel-2: #f2f1ee;
  --panel-3: #e9e7e2;

  --line: rgba(17, 16, 14, .1);
  --line-strong: rgba(17, 16, 14, .18);
  --line-soft: rgba(17, 16, 14, .07);

  --text: #141311;
  --text-dim: #3a3733;
  --muted: #6a655f;
  --muted-2: #8f8a83;

  --accent: #e05a0c;
  --accent-hi: #c24e06;
  --accent-lo: #a84405;
  --accent-soft: rgba(224, 90, 12, .08);
  --accent-line: rgba(224, 90, 12, .3);

  --shadow-xs: 0 1px 2px rgba(17, 16, 14, .06);
  --shadow-sm: 0 2px 6px rgba(17, 16, 14, .06), 0 10px 24px rgba(17, 16, 14, .06);
  --shadow: 0 4px 14px rgba(17, 16, 14, .08), 0 20px 50px rgba(17, 16, 14, .08);
  --shadow-lg: 0 10px 28px rgba(17, 16, 14, .1), 0 40px 90px rgba(17, 16, 14, .12);
  --shadow-accent: 0 4px 14px rgba(224, 90, 12, .18), 0 14px 34px rgba(224, 90, 12, .16);
  --inset-hi: inset 0 1px 0 rgba(255, 255, 255, .85);

  color-scheme: light;
}

/* ── 2. 基础 ────────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  font-feature-settings: "kern" 1, "liga" 1, "calt" 1;
}

/* 全站背景：多层径向渐变 + 噪点（固定，不随滚动） */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(52% 42% at 50% -8%, rgba(232, 93, 4, .13), transparent 70%),
    radial-gradient(38% 34% at 88% 8%, rgba(124, 92, 255, .1), transparent 72%),
    radial-gradient(42% 38% at 6% 26%, rgba(212, 168, 83, .055), transparent 72%),
    var(--bg);
  pointer-events: none;
}
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image: var(--noise);
  background-size: 140px 140px;
  opacity: .032;
  mix-blend-mode: overlay;
  pointer-events: none;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--accent-hi); text-decoration: none; transition: color .2s var(--ease); }
a:hover { color: #ffa06b; }

/* 字距：大字收紧、小字放开 */
h1, h2, h3, h4 {
  margin: 0 0 .55em;
  line-height: 1.18;
  font-weight: 800;
  letter-spacing: -.025em;
  text-wrap: balance;
}
h1 { font-size: clamp(34px, 5vw, 62px); letter-spacing: -.035em; line-height: 1.1; }
h2 { font-size: clamp(26px, 3.3vw, 44px); letter-spacing: -.03em; line-height: 1.16; }
h3 { font-size: clamp(17px, 1.5vw, 21px); letter-spacing: -.015em; line-height: 1.35; }
p { margin: 0 0 1em; }
strong { color: var(--text); font-weight: 700; }

ul { margin: 0; padding-left: 1.15em; }
li { margin: .4em 0; }

:focus-visible {
  outline: 2px solid var(--accent-hi);
  outline-offset: 3px;
  border-radius: 5px;
}

::selection { background: rgba(232, 93, 4, .28); color: #fff; }

@media (hover: hover) {
  ::-webkit-scrollbar { width: 11px; }
  ::-webkit-scrollbar-track { background: #06080c; }
  ::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, #2e3852, #232b3d);
    border-radius: 99px;
    border: 3px solid #06080c;
  }
  ::-webkit-scrollbar-thumb:hover { background: linear-gradient(180deg, #3d4a6b, #2e3852); }
}

/* ── 3. 布局 ────────────────────────────────────────────────────────────── */
.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 26px; }
.narrow { max-width: 860px; }
.center { text-align: center; }
.hide { display: none !important; }

/* 段落节奏：大留白 + 交替密度 */
.section { padding: 112px 0; position: relative; }
.section--alt {
  background: linear-gradient(180deg, rgba(255, 255, 255, .016), transparent 60%), var(--bg-soft);
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
}
.section--tight { padding: 78px 0; }
.section--flush { padding-top: 0; }

.section-head { max-width: 760px; margin-bottom: 56px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head p { color: var(--muted); font-size: 16.5px; margin-bottom: 0; max-width: 640px; }
.section-head.center p { margin-left: auto; margin-right: auto; }

/* 章节眉标（带横线的编辑感标签） */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: 18px;
}
.eyebrow::before {
  content: "";
  width: 26px; height: 1px;
  background: linear-gradient(90deg, var(--accent), transparent);
}
.section-head.center .eyebrow::after {
  content: "";
  width: 26px; height: 1px;
  background: linear-gradient(270deg, var(--accent), transparent);
}

/* 渐变文字（带微弱流光） */
.grad {
  /* B 方案：不用渐变文字，改为同色系的柔和强调 */
  color: var(--accent-hi);
  font-weight: 800;
}

/* ── 4. 按钮 ────────────────────────────────────────────────────────────── */
.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 24px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  color: var(--text);
  font: inherit;
  font-weight: 650;
  font-size: 15px;
  line-height: 1;
  letter-spacing: -.01em;
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  box-shadow: var(--shadow-xs), var(--inset-hi);
  transition: transform .22s var(--ease), box-shadow .25s var(--ease),
              border-color .22s, background .22s, color .2s;
}
.btn:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 255, 255, .2);
  background: linear-gradient(180deg, var(--panel-3), var(--panel-2));
  box-shadow: var(--shadow-sm), var(--inset-hi);
  color: var(--text);
}
.btn:active { transform: translateY(0) scale(.99); }

/* 主按钮：橙渐变 + 流光扫过 + 光晕 */
.btn--primary {
  border-color: transparent;
  color: #fff;
  background: linear-gradient(180deg, var(--accent-fill-1), var(--accent-fill-2));
  box-shadow: var(--shadow-accent), inset 0 1px 0 rgba(255, 255, 255, .28);
}
.btn--primary::after {
  content: "";
  position: absolute;
  top: 0; left: -60%;
  width: 45%; height: 100%;
  background: linear-gradient(100deg, transparent, rgba(255, 255, 255, .38), transparent);
  transform: skewX(-18deg);
  transition: left .7s var(--ease);
  pointer-events: none;
}
.btn--primary:hover::after { left: 130%; }
.btn--primary:hover {
  color: #fff;
  background: linear-gradient(180deg, var(--accent-fill-1), #d3520a 55%, var(--accent-fill-2));
  box-shadow: 0 8px 22px rgba(255, 107, 26, .3), 0 24px 60px rgba(255, 107, 26, .24),
              inset 0 1px 0 rgba(255, 255, 255, .3);
}

.btn--ghost {
  background: rgba(255, 255, 255, .022);
  border-color: var(--line-strong);
  box-shadow: none;
}
.btn--ghost:hover { background: rgba(255, 255, 255, .05); }


.btn--sm { padding: 10px 17px; font-size: 14px; }
.btn--lg { padding: 16px 30px; font-size: 16px; }
.btn--block { width: 100%; }
.btn-row { display: flex; flex-wrap: wrap; gap: 13px; }
.btn-row.center { justify-content: center; }

/* ── 5. 徽标 ────────────────────────────────────────────────────────────── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 13px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--accent-line);
  background: linear-gradient(180deg, rgba(232, 93, 4, .14), rgba(232, 93, 4, .06));
  color: #ffb98d;
  font-size: 12.5px;
  font-weight: 650;
  letter-spacing: .01em;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .06);
}
.badge--muted {
  border-color: var(--line);
  background: rgba(255, 255, 255, .03);
  color: var(--muted);
}
/* 呼吸点 */
.dot-live {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--good);
  box-shadow: 0 0 0 0 rgba(61, 214, 140, .6);
  animation: dot-pulse 2.4s var(--ease-out) infinite;
}
@keyframes dot-pulse {
  0% { box-shadow: 0 0 0 0 rgba(61, 214, 140, .55); }
  70% { box-shadow: 0 0 0 7px rgba(61, 214, 140, 0); }
  100% { box-shadow: 0 0 0 0 rgba(61, 214, 140, 0); }
}

.tag {
  display: inline-block;
  padding: 3px 9px;
  border-radius: 6px;
  background: rgba(255, 255, 255, .04);
  border: 1px solid var(--line-soft);
  font-size: 11.5px;
  color: var(--muted);
}

/* ── 6. 顶部导航 ────────────────────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 900;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  border-bottom: 1px solid transparent;
  background: rgba(8, 10, 15, .45);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  transition: background .3s var(--ease), border-color .3s, box-shadow .3s, height .3s var(--ease);
}
.nav--scrolled {
  height: 58px;
  background: rgba(8, 10, 15, .86);
  border-bottom-color: var(--line);
  box-shadow: 0 1px 0 rgba(255, 255, 255, .04), 0 12px 40px rgba(0, 0, 0, .4);
}
.nav__inner {
  width: 100%; max-width: var(--maxw); margin: 0 auto;
  padding: 0 26px;
  display: flex; align-items: center; gap: 30px;
}

.logo {
  display: inline-flex; align-items: center; gap: 11px;
  color: var(--text); font-weight: 800; font-size: 16.5px; letter-spacing: -.02em;
  flex: 0 0 auto;
}
.logo:hover { color: var(--text); }
.logo__img {
  width: 32px; height: 32px;
  border-radius: 9px;
  display: block;
  filter: drop-shadow(0 4px 12px rgba(232, 93, 4, .28));
  transition: transform .3s var(--ease-spring);
}
.logo:hover .logo__img { transform: scale(1.08) rotate(-3deg); }

.nav__links { display: flex; align-items: center; gap: 3px; flex: 1 1 auto; }
.nav__item { position: relative; }
.nav__link {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 9px 14px;
  border-radius: 10px;
  color: var(--text-dim);
  font-size: 14.5px; font-weight: 550;
  letter-spacing: -.005em;
  transition: color .18s, background .18s;
  position: relative;
}
.nav__link:hover { color: var(--text); background: rgba(255, 255, 255, .045); }
.nav__link[aria-current="page"] { color: var(--text); }
.nav__link[aria-current="page"]::after {
  content: "";
  position: absolute; left: 14px; right: 14px; bottom: 2px;
  height: 2px; border-radius: 2px;
  background: linear-gradient(90deg, var(--accent), transparent);
}
.nav__link .caret {
  width: 7px; height: 7px;
  border-right: 1.6px solid currentColor; border-bottom: 1.6px solid currentColor;
  transform: rotate(45deg) translateY(-2px);
  transition: transform .22s var(--ease);
  opacity: .7;
}
.nav__item--open .nav__link .caret { transform: rotate(-135deg) translateY(-2px); }

.nav__dropdown {
  position: absolute; top: calc(100% + 12px); left: 0;
  min-width: 224px;
  padding: 9px;
  border-radius: var(--radius);
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, #141a26, #0f131c);
  box-shadow: var(--shadow);
  opacity: 0; visibility: hidden; transform: translateY(-8px) scale(.985);
  transform-origin: top left;
  transition: opacity .2s var(--ease), transform .2s var(--ease), visibility .2s;
}
.nav__item--open .nav__dropdown { opacity: 1; visibility: visible; transform: translateY(0) scale(1); }
.nav__dropdown a {
  display: block;
  padding: 10px 13px;
  border-radius: var(--radius-xs);
  color: var(--text-dim);
  font-size: 14px;
  transition: background .16s, color .16s, padding-left .18s var(--ease);
}
.nav__dropdown a:hover { background: rgba(255, 255, 255, .06); color: var(--text); padding-left: 17px; }

.nav__actions { display: flex; align-items: center; gap: 11px; flex: 0 0 auto; }

.nav__burger {
  display: none;
  width: 42px; height: 42px;
  border-radius: 12px;
  border: 1px solid var(--line-strong);
  background: var(--panel);
  cursor: pointer; padding: 0;
  place-items: center;
}
.nav__burger span {
  display: block; width: 17px; height: 1.8px; border-radius: 2px;
  background: var(--text); position: relative;
  transition: background .22s;
}
.nav__burger span::before, .nav__burger span::after {
  content: ""; position: absolute; left: 0; width: 17px; height: 1.8px; border-radius: 2px;
  background: var(--text);
  transition: transform .26s var(--ease);
}
.nav__burger span::before { top: -6px; }
.nav__burger span::after { top: 6px; }
.nav__burger[aria-expanded="true"] span { background: transparent; }
.nav__burger[aria-expanded="true"] span::before { transform: translateY(6px) rotate(45deg); }
.nav__burger[aria-expanded="true"] span::after { transform: translateY(-6px) rotate(-45deg); }

/* 滚动进度条 */
.scroll-progress {
  position: fixed; top: 0; left: 0;
  height: 2px; width: 0;
  z-index: 950;
  background: linear-gradient(90deg, var(--accent), var(--accent-hi));
  box-shadow: 0 0 12px rgba(232, 93, 4, .7);
  transition: width .08s linear;
  pointer-events: none;
}

/* 手机抽屉 */
.drawer {
  position: fixed; inset: var(--nav-h) 0 0 0;
  z-index: 890;
  background: rgba(6, 8, 12, .97);
  backdrop-filter: blur(14px);
  padding: 20px 24px 48px;
  overflow-y: auto;
  opacity: 0; visibility: hidden;
  transform: translateY(-10px);
  transition: opacity .24s var(--ease), transform .24s var(--ease), visibility .24s;
}
.drawer[data-open="true"] { opacity: 1; visibility: visible; transform: translateY(0); }
.drawer a {
  display: block;
  padding: 14px 2px;
  color: var(--text);
  font-size: 16.5px; font-weight: 650;
  border-bottom: 1px solid var(--line-soft);
}
.drawer .drawer__sub a { padding-left: 18px; font-size: 15px; font-weight: 500; color: var(--muted); }
.drawer .btn { margin-top: 22px; }

/* ── 7. 首屏 ────────────────────────────────────────────────────────────── */
.hero {
  position: relative;
  padding: calc(var(--nav-h) + 86px) 0 104px;
  overflow: hidden;
}
/* 漂浮光球（视差由 JS 微调 --py） */
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(58px);
  pointer-events: none;
  translate: var(--mx, 0px) var(--my, 0px);
  transition: translate .5s var(--ease-out);
  will-change: transform;
  z-index: 0;
}
.orb--a {
  width: 520px; height: 520px;
  top: -180px; left: -120px;
  background: radial-gradient(circle, rgba(232, 93, 4, .38), transparent 68%);
  animation: orb-drift 26s ease-in-out infinite;
}
.orb--b {
  width: 460px; height: 460px;
  top: 60px; right: -140px;
  background: radial-gradient(circle, rgba(124, 92, 255, .3), transparent 70%);
  animation: orb-drift 32s ease-in-out infinite reverse;
}
.orb--c {
  width: 380px; height: 380px;
  bottom: -160px; left: 42%;
  background: radial-gradient(circle, rgba(212, 168, 83, .22), transparent 70%);
  animation: orb-drift 38s ease-in-out infinite;
}
@keyframes orb-drift {
  0%, 100% { transform: translate3d(0, 0, 0) scale(1) translateY(var(--py, 0px)); }
  33% { transform: translate3d(36px, -28px, 0) scale(1.08) translateY(var(--py, 0px)); }
  66% { transform: translate3d(-26px, 22px, 0) scale(.96) translateY(var(--py, 0px)); }
}

.hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.02fr .98fr;
  gap: 62px;
  align-items: center;
}
.hero__text > .badge { margin-bottom: 24px; }
.hero h1 { margin-bottom: 22px; }
.hero__lead {
  color: var(--text-dim);
  font-size: 17.5px;
  line-height: 1.85;
  max-width: 560px;
  margin-bottom: 32px;
}
.hero__meta {
  display: flex; flex-wrap: wrap; gap: 34px;
  margin-top: 42px; padding-top: 30px;
  border-top: 1px solid var(--line-soft);
}
.hero__meta div { display: flex; flex-direction: column; gap: 3px; }
.hero__meta b {
  font-size: 21px; color: var(--text);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.02em;
}
.hero__meta span { font-size: 12px; color: var(--muted-2); letter-spacing: .04em; }

/* 首屏网格（径向遮罩，边缘自然消失） */
.hero__grid {
  position: absolute;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .03) 1px, transparent 1px);
  background-size: 68px 68px;
  -webkit-mask-image: radial-gradient(62% 58% at 50% 26%, #000 12%, transparent 76%);
  mask-image: radial-gradient(62% 58% at 50% 26%, #000 12%, transparent 76%);
  pointer-events: none;
}

/* ── 8. 卡片（带鼠标聚光）────────────────────────────────────────────── */
.card {
  position: relative;
  padding: 26px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  box-shadow: var(--shadow-xs), var(--inset-hi);
  transition: transform .3s var(--ease), border-color .3s, box-shadow .3s;
  overflow: hidden;
}
/* 鼠标聚光层（--mx/--my 由 JS 写入） */
.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: radial-gradient(240px circle at var(--mx, 50%) var(--my, 0%),
              rgba(255, 154, 90, .13), transparent 62%);
  opacity: 0;
  transition: opacity .35s;
  pointer-events: none;
}
.card:hover::before { opacity: 1; }

.card--feature { display: flex; flex-direction: column; height: 100%; }
.card--feature:hover {
  transform: translateY(-6px);
  border-color: var(--accent-line);
  box-shadow: var(--shadow), 0 0 0 1px rgba(232, 93, 4, .1) inset;
}
.card__icon {
  position: relative;
  width: 46px; height: 46px;
  border-radius: 13px;
  display: grid; place-items: center;
  background: linear-gradient(150deg, rgba(255, 255, 255, .075), rgba(255, 255, 255, .02));
  border: 1px solid var(--line-strong);
  color: var(--text-dim);
  margin-bottom: 18px;
  box-shadow: var(--inset-hi);
  transition: transform .34s var(--ease-spring), box-shadow .3s, color .3s, border-color .3s;
}
.card--feature:hover .card__icon {
  transform: scale(1.06) rotate(-3deg);
  color: var(--accent-hi);
  border-color: var(--accent-line);
  box-shadow: 0 8px 24px rgba(0, 0, 0, .34);
}
.card__icon svg { width: 22px; height: 22px; }
.card--feature h3 { margin-bottom: 7px; }
.card--feature .tagline { color: var(--muted); font-size: 14px; line-height: 1.7; margin-bottom: 18px; }
.card__points {
  list-style: none; padding: 0; margin: 0 0 20px;
  display: flex; flex-wrap: wrap; gap: 6px;
}
.card__points li {
  margin: 0;
  padding: 4px 10px;
  border-radius: 7px;
  background: rgba(255, 255, 255, .035);
  border: 1px solid var(--line-soft);
  font-size: 11.5px;
  color: var(--muted);
}
.card__more {
  margin-top: auto;
  font-size: 14px; font-weight: 650;
  color: var(--accent-hi);
  display: inline-flex; align-items: center; gap: 7px;
  transition: gap .25s var(--ease);
}
.card--feature:hover .card__more { gap: 12px; }

/* 渠道卡 */
.card--channel { display: flex; flex-direction: column; gap: 7px; padding: 22px; }
.channel__head { display: flex; align-items: center; gap: 11px; margin-bottom: 3px; }
.channel__name { font-weight: 750; font-size: 15.5px; letter-spacing: -.01em; }
.channel__desc { color: var(--muted); font-size: 12.8px; line-height: 1.65; margin-bottom: 16px; }
.card--channel .btn { margin-top: auto; }
.card--channel.is-recommend {
  border-color: var(--accent-line);
  background: linear-gradient(180deg, rgba(255, 107, 26, .07), var(--panel) 58%);
}
.card--channel.is-recommend::after {
  content: "";
  position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), var(--accent-hi), var(--accent), transparent);
  background-size: 200% 100%;
  animation: sheen 4.5s linear infinite;
}
@keyframes sheen {
  0% { background-position: -100% 0; }
  100% { background-position: 200% 0; }
}

/* ── 9. 网格 ────────────────────────────────────────────────────────────── */
.grid { display: grid; gap: var(--gap); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--auto { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }

/* ── 10. 截图容器（设备框）─────────────────────────────────────────────── */
.shot {
  position: relative;
  border-radius: var(--radius);
  border: 1px solid var(--line-strong);
  background: var(--panel);
  overflow: hidden;
  box-shadow: var(--shadow), var(--inset-hi);
}
.shot img { width: 100%; display: block; }
.shot__caption {
  display: block;
  padding: 11px 15px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px;
  color: var(--muted-2);
  background: rgba(0, 0, 0, .22);
}
.shot--island {
  background:
    radial-gradient(circle at 50% 42%, rgba(232, 93, 4, .1), transparent 62%),
    radial-gradient(circle at 50% 50%, #1b2130, #080a0f 74%);
  padding: 26px;
}

/* ── 11. 键帽 / 表格 ───────────────────────────────────────────────────── */
.kbd {
  display: inline-block;
  min-width: 27px;
  padding: 4px 9px;
  border-radius: 7px;
  border: 1px solid var(--line-strong);
  border-bottom-width: 2px;
  background: linear-gradient(180deg, var(--panel-3), var(--panel-2));
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 12px;
  text-align: center;
  box-shadow: var(--inset-hi);
}
.hotkey-table { width: 100%; border-collapse: collapse; }
.hotkey-table td { padding: 12px 8px; border-bottom: 1px solid var(--line-soft); vertical-align: middle; }
.hotkey-table tr:last-child td { border-bottom: 0; }
.hotkey-table td:first-child { width: 46%; }
.hotkey-table td:last-child { color: var(--text-dim); font-size: 14.5px; }

/* ── 12. FAQ ────────────────────────────────────────────────────────────── */
.faq-group { margin-bottom: 40px; }
.faq-group > h3 {
  font-size: 12px; color: var(--muted-2);
  text-transform: uppercase; letter-spacing: .14em;
  margin-bottom: 14px;
}
.faq {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  margin-bottom: 11px;
  overflow: hidden;
  transition: border-color .25s, background .25s, box-shadow .25s;
}
.faq:hover { border-color: var(--line-strong); }
.faq[open] {
  border-color: var(--accent-line);
  box-shadow: 0 10px 34px rgba(0, 0, 0, .3), 0 0 0 1px rgba(232, 93, 4, .1) inset;
}
.faq summary {
  cursor: pointer;
  padding: 18px 22px;
  font-weight: 650;
  font-size: 15.5px;
  list-style: none;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  width: 8px; height: 8px; flex: 0 0 auto;
  border-right: 1.8px solid var(--muted); border-bottom: 1.8px solid var(--muted);
  transform: rotate(45deg) translateY(-2px);
  transition: transform .26s var(--ease), border-color .2s;
}
.faq[open] summary::after { transform: rotate(-135deg) translateY(-2px); border-color: var(--accent-hi); }
.faq__body { padding: 0 22px 20px; color: var(--muted); font-size: 14.5px; line-height: 1.8; }
.faq__body p:last-child { margin-bottom: 0; }

/* ── 13. 时间线 ─────────────────────────────────────────────────────────── */
.timeline { position: relative; padding-left: 30px; }
.timeline::before {
  content: ""; position: absolute; left: 7px; top: 8px; bottom: 8px; width: 1px;
  background: linear-gradient(180deg, var(--accent-line), var(--line) 55%, transparent);
}
.timeline__item { position: relative; padding-bottom: 38px; }
.timeline__item::before {
  content: ""; position: absolute; left: -30px; top: 8px;
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--bg); border: 2px solid var(--accent);
  transition: box-shadow .3s;
}
.timeline__item:first-child::before { box-shadow: 0 0 0 5px var(--accent-soft), 0 0 18px rgba(232, 93, 4, .5); }
.timeline__head { display: flex; flex-wrap: wrap; align-items: center; gap: 11px; margin-bottom: 9px; }
.timeline__ver { font-weight: 800; font-size: 17px; letter-spacing: -.02em; }
.timeline__date { font-size: 12px; color: var(--muted-2); font-variant-numeric: tabular-nums; }
.timeline ul { color: var(--muted); font-size: 14.5px; }

/* ── 14. 弹层 ───────────────────────────────────────────────────────────── */
.modal {
  position: fixed; inset: 0; z-index: 1000;
  display: grid; place-items: center;
  padding: 22px;
  background: rgba(3, 4, 7, .78);
  backdrop-filter: blur(6px);
  opacity: 0; visibility: hidden;
  transition: opacity .22s var(--ease), visibility .22s;
}
.modal[data-open="true"] { opacity: 1; visibility: visible; }
.modal__box {
  position: relative;
  width: 100%; max-width: 410px;
  padding: 30px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  box-shadow: var(--shadow-lg), var(--inset-hi);
  transform: translateY(14px) scale(.97);
  transition: transform .3s var(--ease-out);
  text-align: center;
}
.modal[data-open="true"] .modal__box { transform: translateY(0) scale(1); }
.modal__code {
  font-family: var(--font-mono);
  font-size: 32px; font-weight: 700;
  letter-spacing: .2em;
  color: var(--accent-hi);
  background: linear-gradient(180deg, rgba(255, 107, 26, .13), rgba(255, 107, 26, .05));
  border: 1px dashed var(--accent-line);
  border-radius: var(--radius);
  padding: 16px;
  margin: 18px 0 20px;
  user-select: all;
  text-shadow: 0 0 24px rgba(255, 134, 66, .4);
}
.modal__close {
  position: absolute; top: 12px; right: 13px;
  width: 34px; height: 34px; border-radius: 9px;
  border: 0; background: transparent; color: var(--muted);
  font-size: 21px; cursor: pointer;
  transition: background .18s, color .18s;
}
.modal__close:hover { background: rgba(255, 255, 255, .07); color: var(--text); }

/* ── 15. 页脚 ───────────────────────────────────────────────────────────── */
.footer {
  border-top: 1px solid var(--line-soft);
  background: linear-gradient(180deg, var(--bg-soft), #06080c);
  padding: 64px 0 32px;
  font-size: 14px;
}
.footer__grid { display: grid; grid-template-columns: 1.5fr repeat(3, 1fr); gap: 40px; }
.footer__brand p { color: var(--muted); margin: 16px 0 0; max-width: 310px; font-size: 13.5px; line-height: 1.75; }
.footer h4 {
  font-size: 11.5px; color: var(--muted-2);
  text-transform: uppercase; letter-spacing: .13em;
  margin-bottom: 14px; font-weight: 700;
}
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer li { margin: 0 0 10px; }
.footer a { color: var(--muted); font-size: 13.5px; transition: color .18s, padding-left .2s var(--ease); }
.footer a:hover { color: var(--text); }
.footer__bottom {
  margin-top: 46px; padding-top: 22px;
  border-top: 1px solid var(--line-soft);
  display: flex; flex-wrap: wrap; gap: 12px; justify-content: space-between;
  color: var(--muted-2); font-size: 12.5px;
}

/* ── 16. 页头 / 面包屑 / 翻页 ──────────────────────────────────────────── */
.crumbs {
  display: flex; align-items: center; gap: 9px;
  font-size: 12.5px; color: var(--muted-2); margin-bottom: 20px;
}
.crumbs a { color: var(--muted); }
.crumbs span { opacity: .5; }

.page-head {
  padding: calc(var(--nav-h) + 64px) 0 56px;
  position: relative; overflow: hidden;
}
.page-head h1 { font-size: clamp(30px, 3.8vw, 48px); margin-bottom: 14px; }
.page-head p { color: var(--text-dim); font-size: 17px; max-width: 680px; margin-bottom: 0; line-height: 1.8; }

.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-top: 22px; }
.pager a {
  padding: 20px 22px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  display: flex; flex-direction: column; gap: 5px;
  box-shadow: var(--shadow-xs), var(--inset-hi);
  transition: border-color .25s, transform .25s var(--ease), box-shadow .25s;
}
.pager a:hover {
  border-color: var(--accent-line);
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm), var(--inset-hi);
  color: var(--text);
}
.pager small { color: var(--muted-2); font-size: 11.5px; letter-spacing: .05em; }
.pager b { font-size: 15.5px; }
.pager .pager--next { text-align: right; }

/* ── 17. 结尾 CTA ───────────────────────────────────────────────────────── */
.cta {
  position: relative;
  padding: 96px 0;
  text-align: center;
  overflow: hidden;
  border-top: 1px solid var(--line-soft);
  background:
    radial-gradient(58% 130% at 50% 0%, rgba(232, 93, 4, .2), transparent 66%),
    radial-gradient(40% 90% at 82% 110%, rgba(124, 92, 255, .12), transparent 70%),
    var(--bg-soft);
}
.cta::after {
  content: "";
  position: absolute; inset: 0;
  background-image: var(--noise);
  background-size: 140px 140px;
  opacity: .03;
  mix-blend-mode: overlay;
  pointer-events: none;
}
.cta h2 { margin-bottom: 12px; position: relative; }
.cta p { color: var(--muted); margin-bottom: 30px; position: relative; }
.cta .btn-row { position: relative; }

/* ── 18. 动效基元 ───────────────────────────────────────────────────────── */
/* 入场：位移 + 模糊 + 淡入（比单纯 fade 更"高级"） */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  filter: blur(10px);
  transition:
    opacity .7s var(--ease-out),
    transform .7s var(--ease-out),
    filter .7s var(--ease-out);
  transition-delay: var(--d, 0ms);
}
.reveal.is-in { opacity: 1; transform: none; filter: none; }

/* 数字滚动（JS 写 --nv） */
.count {
  font-variant-numeric: tabular-nums;
  letter-spacing: -.02em;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; filter: none; transition: none; }
  .grad { animation: none; }
  .orb { animation: none; }
  .dot-live { animation: none; }
  .card--channel.is-recommend::after { animation: none; }
  .btn--primary::after { display: none; }
  * { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}

/* ── 19. 响应式 ─────────────────────────────────────────────────────────── */
@media (max-width: 1100px) {
  .hero__inner { gap: 44px; }
}

@media (max-width: 1024px) {
  .section { padding: 88px 0; }
  .hero { padding: calc(var(--nav-h) + 60px) 0 80px; }
  .hero__inner { grid-template-columns: 1fr; gap: 48px; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .hero__lead { max-width: none; }
}

@media (max-width: 880px) {
  :root { --nav-h: 60px; }
  .nav__links { display: none; }
  .nav__burger { display: grid; }
  .nav--scrolled { height: 56px; }
  .nav__actions .btn--nav-cta { display: none; }
  .nav__inner { gap: 14px; justify-content: space-between; }
}

@media (max-width: 640px) {
  body { font-size: 15.5px; line-height: 1.78; }
  .section { padding: 64px 0; }
  .section--tight { padding: 48px 0; }
  .section-head { margin-bottom: 36px; }
  .wrap { padding: 0 18px; }
  .hero { padding: calc(var(--nav-h) + 44px) 0 60px; }
  .hero__lead { font-size: 15.8px; }
  .hero__meta { gap: 22px; margin-top: 32px; padding-top: 24px; }
  .hero__meta b { font-size: 18px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
  .pager { grid-template-columns: 1fr; }
  .pager .pager--next { text-align: left; }
  .footer__grid { grid-template-columns: 1fr; gap: 28px; }
  .footer { padding: 48px 0 26px; }
  .btn-row .btn { width: 100%; }
  .hotkey-table td:first-child { width: 50%; }
  .modal__code { font-size: 25px; letter-spacing: .14em; }
  .cta { padding: 68px 0; }
  .orb { filter: blur(40px); opacity: .75; }
  .card { padding: 22px; }
}

/* 触屏设备关闭悬停位移（避免"粘住"） */
@media (hover: none) {
  .card--feature:hover,
  .btn:hover,
  .pager a:hover { transform: none; }
  .card::before { display: none; }
}

/* ── 20. 打印 ───────────────────────────────────────────────────────────── */
@media print {
  .nav, .drawer, .footer, .cta, .modal, .scroll-progress, .orb { display: none !important; }
  body { background: #fff; color: #000; }
  body::before, body::after { display: none; }
  .card, .shot, .faq { border-color: #ccc; background: #fff; box-shadow: none; }
}

/* ══════════════════════════════════════════════════════════════════════════
   亮色模式：组件级覆盖
   （只在 html[data-mode="light"] 下生效；深色模式不受影响）
   ══════════════════════════════════════════════════════════════════════════ */
html[data-mode="light"] body::before {
  background:
    radial-gradient(50% 40% at 50% -6%, rgba(224, 90, 12, .06), transparent 72%),
    radial-gradient(38% 32% at 88% 10%, rgba(20, 40, 80, .05), transparent 74%),
    var(--bg);
}
html[data-mode="light"] body::after { opacity: .02; mix-blend-mode: multiply; }

/* 导航 */
html[data-mode="light"] .nav { background: rgba(246, 245, 243, .72); }
html[data-mode="light"] .nav--scrolled {
  background: rgba(246, 245, 243, .93);
  border-bottom-color: var(--line);
  box-shadow: 0 1px 0 rgba(17, 16, 14, .06), 0 10px 30px rgba(17, 16, 14, .07);
}
html[data-mode="light"] .nav__link:hover { background: rgba(17, 16, 14, .05); }
html[data-mode="light"] .nav__dropdown {
  background: #fff;
  box-shadow: var(--shadow);
}
html[data-mode="light"] .nav__dropdown a:hover { background: rgba(17, 16, 14, .05); }
html[data-mode="light"] .drawer { background: rgba(246, 245, 243, .98); }

/* 按钮 */
html[data-mode="light"] .btn {
  background: #fff;
  border-color: var(--line-strong);
  box-shadow: var(--shadow-xs), var(--inset-hi);
}
html[data-mode="light"] .btn:hover { background: var(--panel-2); border-color: rgba(17, 16, 14, .24); }
html[data-mode="light"] .btn--ghost { background: transparent; }
html[data-mode="light"] .btn--primary {
  background: linear-gradient(180deg, var(--accent-fill-1), var(--accent-fill-2));
  border-color: transparent;
  color: #fff;
  box-shadow: var(--shadow-accent), inset 0 1px 0 rgba(255, 255, 255, .25);
}
html[data-mode="light"] .btn--primary:hover {
  background: linear-gradient(180deg, #c94e08, #bf4a07);
  color: #fff;
}
html[data-mode="light"] .btn--primary::after { background: linear-gradient(100deg, transparent, rgba(255, 255, 255, .5), transparent); }

/* 表面 */
html[data-mode="light"] .card,
html[data-mode="light"] .value-item,
html[data-mode="light"] .capability,
html[data-mode="light"] .pager a,
html[data-mode="light"] .faq,
html[data-mode="light"] .link-diagram,
html[data-mode="light"] .dl-fact,
html[data-mode="light"] .update-strip,
html[data-mode="light"] .latest-release,
html[data-mode="light"] .android-card,
html[data-mode="light"] .modal__box {
  background: #fff;
}
html[data-mode="light"] .card::before {
  background: radial-gradient(240px circle at var(--mx, 50%) var(--my, 0%), rgba(224, 90, 12, .06), transparent 62%);
}
html[data-mode="light"] .card__points li { background: rgba(17, 16, 14, .045); }
html[data-mode="light"] .card__icon {
  background: linear-gradient(150deg, rgba(17, 16, 14, .06), rgba(17, 16, 14, .015));
}
html[data-mode="light"] .kbd { background: #fff; }
html[data-mode="light"] .tag { background: rgba(17, 16, 14, .05); }
html[data-mode="light"] .badge--muted { background: rgba(17, 16, 14, .04); }
html[data-mode="light"] .value-item .vi-icon { background: linear-gradient(150deg, rgba(17, 16, 14, .06), rgba(17, 16, 14, .015)); }
html[data-mode="light"] .faq:hover { border-color: var(--line-strong); }
html[data-mode="light"] .modal { background: rgba(20, 19, 17, .38); }

/* 页脚 / CTA */
html[data-mode="light"] .footer { background: #f1efeb; }
html[data-mode="light"] .cta {
  background:
    radial-gradient(56% 130% at 50% 0%, rgba(224, 90, 12, .1), transparent 68%),
    var(--bg-soft);
}
html[data-mode="light"] .cta::after { opacity: .018; }

/* 首屏网格与光球 */
html[data-mode="light"] .hero__grid {
  background-image:
    linear-gradient(rgba(17, 16, 14, .05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(17, 16, 14, .05) 1px, transparent 1px);
}
html[data-mode="light"] .orb--a { background: radial-gradient(circle, rgba(224, 90, 12, .12), transparent 72%); }
html[data-mode="light"] .orb--b { background: radial-gradient(circle, rgba(20, 40, 80, .08), transparent 74%); }
html[data-mode="light"] .orb--c { display: none; }

/* 设备框刻意保持深色：深色界面截图在浅底上更突出（不覆盖） */


html[data-mode="light"] .footer__bottom { color: var(--muted-2); }

/* 滚动条 */
html[data-mode="light"]::-webkit-scrollbar-track { background: #efede8; }
html[data-mode="light"]::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, #cfcbc3, #bdb9b0);
  border-color: #efede8;
}
html[data-mode="light"] ::selection { background: rgba(224, 90, 12, .18); color: #141311; }

/* ── 明暗切换按钮 ───────────────────────────────────────────────────────── */
.nav__mode {
  width: 38px; height: 38px;
  display: inline-grid; place-items: center;
  border-radius: 11px;
  border: 1px solid var(--line-strong);
  background: var(--panel);
  color: var(--text-dim);
  cursor: pointer;
  padding: 0;
  transition: background .2s, color .2s, border-color .2s, transform .2s var(--ease);
}
.nav__mode:hover {
  background: var(--panel-2);
  color: var(--text);
  border-color: var(--line-strong);
  transform: translateY(-1px);
}
.nav__mode .mode-icon { display: grid; place-items: center; line-height: 0; }
.nav__mode .mode-icon--sun { display: none; }
html[data-mode="light"] .nav__mode .mode-icon--moon { display: none; }
html[data-mode="light"] .nav__mode .mode-icon--sun { display: grid; }
@media (max-width: 880px) {
  .nav__mode { width: 36px; height: 36px; }
}

/* ── 可读性修正（对比度审计后调整）─────────────────────────────────────────
   白色文字压在亮橙上对比不足 3:1，故主按钮改用比强调色深一档的"填充色"；
   强调色本身保持鲜亮，仅用于文字与描边（满足 8.24:1）。 */
:root {
  --accent-fill-1: #e85c0d;   /* 白字 3.52:1 */
  --accent-fill-2: #c54a07;   /* 白字 4.82:1 */
}
html[data-mode="light"] {
  --accent-hi: #b04605;       /* 亮色模式下的链接色：5.18:1（原 #c24e06 仅 4.39） */
  --accent-fill-1: #d4540a;   /* 白字 4.14:1 */
  --accent-fill-2: #bf4a07;   /* 白字 5.00:1 */
}

/* ── 语言切换 ───────────────────────────────────────────────────────────── */
.nav__lang {
  display: inline-flex; align-items: center; justify-content: center;
  height: 38px; min-width: 44px;
  padding: 0 12px;
  border-radius: 11px;
  border: 1px solid var(--line-strong);
  background: var(--panel);
  color: var(--text-dim);
  font-size: 12.5px;
  font-weight: 650;
  letter-spacing: .02em;
  transition: background .2s, color .2s, border-color .2s, transform .2s var(--ease);
}
.nav__lang:hover {
  background: var(--panel-2);
  color: var(--text);
  transform: translateY(-1px);
}
@media (max-width: 880px) {
  .nav__lang { height: 36px; min-width: 40px; padding: 0 10px; font-size: 12px; }
}