/* 芙芙启动器官网 · 配色与动效节拍对齐启动器内 ThemeManager / MotionKit
   深色为默认，浅色由 [data-theme="light"] 覆盖，主色由 [data-accent] 覆盖 */

:root {
  --bg: #101418;
  --surface: #1A2027;
  --surface-2: #232B35;
  --text: #E8ECF1;
  --dim: #8A93A0;
  --border: #2A323D;
  --primary: #4C8DFF;
  --primary-hover: #6BA1FF;
  --on-primary: #FFFFFF;
  --success: #3FB27F;
  --warning: #E0A93E;
  --danger: #E25D5D;

  --t-fast: 160ms;
  --t-mid: 240ms;
  --t-slow: 320ms;
  --ease-out: cubic-bezier(.22, .61, .36, 1);
  --ease-back: cubic-bezier(.34, 1.4, .64, 1);

  --radius: 18px;
  --radius-sm: 12px;
  --wrap: 1180px;
  --nav-h: 68px;
  --shadow: 0 18px 48px rgba(0, 0, 0, .42);
  --font: "Microsoft YaHei UI", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  --mono: Consolas, "Cascadia Mono", "Courier New", monospace;
}

[data-theme="light"] {
  --bg: #F3F5F9;
  --surface: #FFFFFF;
  --surface-2: #EAEFF6;
  --text: #20242C;
  --dim: #6A7382;
  --border: #DCE3ED;
  --primary: #3B7BEC;
  --primary-hover: #2F6AD0;
  --on-primary: #FFFFFF;
  --shadow: 0 18px 44px rgba(31, 45, 71, .13);
}

/* 主色由 layout.js 按卡片上的 data-primary 写成行内变量，这里只给默认值 */

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 14px); }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  transition: background var(--t-mid) var(--ease-out), color var(--t-mid) var(--ease-out);
}

.sprite { display: none; }

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

a { color: inherit; text-decoration: none; }

h1, h2, h3, h4 { margin: 0; font-weight: 700; line-height: 1.28; letter-spacing: .2px; }

p { margin: 0; }

code {
  font-family: var(--mono);
  font-size: .88em;
  padding: 1px 5px;
  border-radius: 5px;
  overflow-wrap: anywhere;
  background: var(--surface-2);
  color: var(--text);
}

.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 26px; }

.ic { width: 1.15em; height: 1.15em; flex: none; }

/* ───────────────────────────── 导航 ───────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px) saturate(150%);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t-mid) var(--ease-out), background var(--t-mid) var(--ease-out);
}

.nav.scrolled { border-bottom-color: var(--border); }

/* 阅读进度条，宽度由 layout.js 写成 --p */
.nav::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--primary-hover));
  transform: scaleX(var(--p, 0));
  transform-origin: left center;
  opacity: 0;
  transition: opacity var(--t-mid) var(--ease-out);
  pointer-events: none;
}

.nav.scrolled::after { opacity: .9; }

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  padding: 11px 20px;
  border: 1px solid var(--primary);
  border-radius: 0 0 12px 0;
  background: var(--surface);
  color: var(--text);
  font-size: 14px;
}

.skip:focus { left: 0; }

.nav-inner { display: flex; align-items: center; gap: 20px; height: var(--nav-h); }

.brand { display: flex; align-items: center; gap: 11px; margin-right: auto; }

.brand-logo { width: 40px; height: 40px; border-radius: 11px; box-shadow: 0 0 0 1px var(--border); }

.brand-text { display: flex; flex-direction: column; line-height: 1.15; }

.brand-text strong { font-size: 17px; }

.brand-text em {
  font-style: normal;
  font-size: 10px;
  letter-spacing: 1.6px;
  color: var(--dim);
}

.nav-links { display: flex; gap: 4px; }

.nav-links a {
  position: relative;
  padding: 8px 13px;
  border-radius: 9px;
  font-size: 14.5px;
  color: var(--dim);
  transition: color var(--t-fast) var(--ease-out), background var(--t-fast) var(--ease-out);
}

.nav-links a:hover { color: var(--text); background: var(--surface); }

.nav-links a.active { color: var(--text); }

.nav-links a.active::after {
  content: "";
  position: absolute;
  left: 13px;
  right: 13px;
  bottom: 2px;
  height: 2px;
  border-radius: 2px;
  background: var(--primary);
}

.nav-actions { display: flex; align-items: center; gap: 10px; }

.icon-btn {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  transition: border-color var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-back);
}

.icon-btn:hover { border-color: var(--primary); transform: translateY(-1px); }

.icon-btn .ic { width: 19px; height: 19px; }

#modeToggle .ic-sun { display: none; }

[data-theme="light"] #modeToggle .ic-sun { display: block; }
[data-theme="light"] #modeToggle .ic-moon { display: none; }

.nav-burger { display: none; }

/* ───────────────────────────── 按钮 ───────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 12px 22px;
  border: 1px solid transparent;
  border-radius: 12px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--t-fast) var(--ease-out), border-color var(--t-fast) var(--ease-out),
              color var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-back),
              box-shadow var(--t-mid) var(--ease-out);
}

.btn-primary {
  background: var(--primary);
  color: var(--on-primary);
  box-shadow: 0 10px 26px color-mix(in srgb, var(--primary) 28%, transparent);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 14px 32px color-mix(in srgb, var(--primary) 38%, transparent);
}

.btn-ghost {
  background: color-mix(in srgb, var(--surface) 70%, transparent);
  border-color: var(--border);
  color: var(--text);
}

.btn-ghost:hover { border-color: var(--primary); transform: translateY(-2px); }

.btn-sm { padding: 9px 16px; font-size: 14px; border-radius: 10px; }
.btn-lg { padding: 15px 26px; font-size: 16px; border-radius: 13px; }

.btn:active { transform: translateY(0) scale(.985); }

/* ───────────────────────────── 首屏 ───────────────────────────── */
.hero { position: relative; padding: 74px 0 0; }

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    url(../img/hero-scenic.jpg) center top / cover no-repeat,
    url(../img/hero-bg.jpg) center top / cover no-repeat #0d1116;
  opacity: 1;
}

.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, color-mix(in srgb, var(--bg) 92%, transparent),
                    color-mix(in srgb, var(--bg) 62%, transparent) 54%,
                    color-mix(in srgb, var(--bg) 22%, transparent) 100%),
    linear-gradient(to bottom, color-mix(in srgb, var(--bg) 30%, transparent), var(--bg) 94%);
}

[data-theme="light"] .hero-bg { opacity: .5; }

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 1.18fr);
  align-items: center;
  gap: 52px;
  padding-bottom: 62px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0 0 20px;
  padding: 6px 14px 6px 11px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: color-mix(in srgb, var(--surface) 76%, transparent);
  font-size: 13px;
  color: var(--dim);
}

.badge .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--success) 22%, transparent);
}

.hero h1 {
  font-size: clamp(38px, 5.4vw, 60px);
  letter-spacing: 1px;
}

.hero-en {
  display: block;
  margin-top: 6px;
  font-size: clamp(19px, 2.1vw, 25px);
  font-weight: 400;
  letter-spacing: 3.4px;
  color: var(--primary);
}

.hero-sub {
  margin: 14px 0 16px;
  font-size: 13px;
  letter-spacing: 2.6px;
  color: var(--dim);
}

.hero-lead { font-size: 16.5px; color: var(--text); max-width: 33em; }

.only-wide { display: inline; }

.hero-cta { display: flex; flex-wrap: wrap; gap: 13px; margin: 28px 0 22px; }

.hero-cta .btn { white-space: normal; text-align: left; }

.hero-meta { margin: 0; padding: 0; list-style: none; display: grid; gap: 7px; }

.hero-meta li { display: flex; align-items: center; gap: 9px; font-size: 14px; color: var(--dim); }

.hero-meta .ic { width: 16px; height: 16px; color: var(--success); }

/* 无边框窗口样机 */
.window {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform var(--t-slow) var(--ease-back), box-shadow var(--t-slow) var(--ease-out),
              border-color var(--t-mid) var(--ease-out);
}

.hero-shot .window:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--primary) 55%, var(--border));
  box-shadow: 0 26px 60px color-mix(in srgb, var(--primary) 16%, rgba(0, 0, 0, .45));
}

.window-bar {
  display: flex;
  align-items: center;
  height: 54px;
  padding: 0 14px 0 18px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--surface-2), var(--surface));
}

.window-brand { display: flex; align-items: center; gap: 9px; margin-right: auto; }

.window-brand img { border-radius: 7px; }

.window-brand b { font-size: 15px; }

.window-brand i {
  font-style: normal;
  font-size: 10px;
  letter-spacing: 1.5px;
  color: var(--dim);
  padding-left: 9px;
  border-left: 1px solid var(--border);
}

.window-btns { display: flex; align-items: center; gap: 14px; }

.window-btns i { width: 11px; height: 11px; border: 1.4px solid var(--dim); border-radius: 2px; }

.window-btns i.x { border-color: var(--danger); }

.window-body { background: #000; }

.window-body img { width: 100%; height: auto; }

.shot-cap {
  margin-top: 12px;
  font-size: 13px;
  color: var(--dim);
  text-align: center;
}

/* 数据条 */
.stats {
  position: relative;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
  padding: 22px 26px;
  margin-bottom: -46px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.stat { display: flex; align-items: baseline; gap: 10px; }

.stat b { font-size: 30px; color: var(--primary); line-height: 1; }

.stat span { font-size: 12.5px; line-height: 1.5; color: var(--dim); }

/* ───────────────────────────── 区块 ───────────────────────────── */
.section { padding: 108px 0; position: relative; }

.section-alt { background: var(--surface); border-block: 1px solid var(--border); }

.sec-head { max-width: 720px; margin-bottom: 42px; }

.kicker {
  margin: 0 0 12px;
  font-size: 12.5px;
  letter-spacing: 2.4px;
  color: var(--primary);
  font-weight: 700;
}

.sec-head h2 { font-size: clamp(26px, 3.4vw, 36px); }

.sec-sub { margin-top: 14px; font-size: 15.5px; color: var(--dim); }

.grid { display: grid; gap: 18px; }

.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.card {
  padding: 26px 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  transition: transform var(--t-mid) var(--ease-back), border-color var(--t-fast) var(--ease-out),
              box-shadow var(--t-mid) var(--ease-out), background var(--t-mid) var(--ease-out);
}

.section-alt .card { background: var(--bg); }

.card:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--primary) 60%, var(--border));
  box-shadow: 0 16px 34px rgba(0, 0, 0, .26);
}

.card-ic {
  width: 26px;
  height: 26px;
  margin-bottom: 14px;
  padding: 5px;
  border-radius: 9px;
  background: color-mix(in srgb, var(--primary) 16%, transparent);
  color: var(--primary);
}

.card h3 { font-size: 17.5px; }

.card .en {
  margin: 3px 0 10px;
  font-size: 11px;
  letter-spacing: 1.6px;
  color: var(--dim);
  text-transform: uppercase;
}

.card h3 + p:not(.en) { margin-top: 10px; }

.card p { font-size: 14.2px; color: var(--dim); }

.card .en + p { margin-top: 0; }

.card-lg { position: relative; padding: 30px 27px; }

.card-lg h3 { font-size: 19.5px; }

.card-lg > p { margin: 12px 0 14px; font-size: 14.6px; }

.tag {
  position: absolute;
  top: 26px;
  right: 24px;
  padding: 3px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 11.5px;
  color: var(--dim);
  background: var(--surface);
}

.tag-ai { color: var(--primary); border-color: color-mix(in srgb, var(--primary) 45%, var(--border)); }

.ticks { margin: 0; padding: 0; list-style: none; display: grid; gap: 9px; }

.ticks li {
  position: relative;
  padding-left: 21px;
  font-size: 13.8px;
  color: var(--dim);
  line-height: 1.62;
}

.ticks li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: .62em;
  width: 8px;
  height: 4px;
  border-left: 1.8px solid var(--success);
  border-bottom: 1.8px solid var(--success);
  transform: rotate(-45deg);
}

.loader-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 4px; }

.loader {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 12px 6px 8px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
  font-size: 13px;
  transition: border-color var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-back);
}

.loader:hover { border-color: var(--primary); transform: translateY(-2px); }

.loader img { border-radius: 6px; }

.note {
  display: flex;
  align-items: flex-start;
  gap: 11px;
  margin-top: 30px;
  padding: 18px 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-size: 14px;
  color: var(--dim);
}

.note .ic { width: 19px; height: 19px; margin-top: 3px; color: var(--primary); }

.note > span { min-width: 0; }

/* ───────────────────────────── 界面预览 ───────────────────────────── */
.preview-frame { margin-bottom: 26px; }

.window-lg .window-body { background: #05070a; }

/* ───────────────────────────── 主题展示 ───────────────────────────── */
.theme-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.theme-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  margin: 0;
  padding: 0;
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: inherit;
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: transform var(--t-mid) var(--ease-back), border-color var(--t-fast) var(--ease-out),
              box-shadow var(--t-mid) var(--ease-out);
}

.theme-card img {
  width: 100%;
  height: auto;
  flex: none;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: center 34%;
}

.theme-card .theme-meta { margin-top: auto; }

.theme-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 34px rgba(0, 0, 0, .3);
}

.theme-card.active {
  border-color: var(--primary);
  box-shadow: 0 0 0 1px var(--primary), 0 16px 34px color-mix(in srgb, var(--primary) 22%, rgba(0, 0, 0, .3));
}

.theme-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 13px 15px;
  border-top: 1px solid var(--border);
}

.theme-meta b { font-size: 14.5px; font-weight: 700; }

.theme-meta code { font-size: 12px; color: var(--dim); background: none; padding: 0; }

.theme-card.active .theme-meta code { color: var(--primary); }

.theme-note {
  cursor: default;
  background: color-mix(in srgb, var(--surface) 60%, transparent);
}

.theme-note:hover { transform: none; box-shadow: none; }

.theme-note-body { display: block; padding: 22px 20px; }

.theme-note b { display: block; margin-bottom: 8px; font-size: 15.5px; }

.theme-note p { font-size: 13.6px; color: var(--dim); }

.theme-strip { margin-top: 26px; }

.theme-strip .theme-card { height: 100%; }

.theme-more {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 20px;
}

.hint { font-size: 13px; color: var(--dim); }

.tag-inline {
  display: inline-block;
  margin-left: 10px;
  padding: 3px 11px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--success) 18%, transparent);
  color: var(--success);
  font-size: 12.5px;
  font-weight: 700;
  vertical-align: 3px;
}

.lite-card a.btn { margin-top: 14px; }

.lite-card a.btn .ic { width: 15px; height: 15px; }

/* ───────────────────────────── 下载区 ───────────────────────────── */
.download { overflow: hidden; }

.dl-bg {
  position: absolute;
  inset: 0;
  background:
    url(../img/dl-scenic.jpg) center / cover no-repeat,
    url(../img/hero-bg.jpg) center / cover no-repeat #0d1116;
  opacity: .16;
  pointer-events: none;
}

[data-theme="light"] .dl-bg { opacity: .3; }

.dl-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, var(--bg), color-mix(in srgb, var(--bg) 72%, transparent) 45%, var(--bg));
}

.download .wrap { position: relative; }

.dl-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: 20px;
  align-items: start;
}

.dl-card, .qq-card, .lite-card {
  padding: 28px 28px 30px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.dl-card h3 { font-size: 17px; }

.dl-card h3.mt { margin-top: 26px; }

.dl-list { margin: 16px 0 0; display: grid; gap: 11px; }

.dl-list > div {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 14px;
  padding-bottom: 11px;
  border-bottom: 1px solid var(--border);
}

.dl-list > div:last-child { border-bottom: 0; padding-bottom: 0; }

.dl-list dt { font-size: 13px; color: var(--dim); }

.dl-list dd { margin: 0; font-size: 14.3px; }

.req { margin: 0; padding: 0; list-style: none; display: grid; gap: 10px; margin-top: 14px; }

.req li { display: flex; align-items: flex-start; gap: 10px; font-size: 14.2px; color: var(--dim); }

.req .ic { width: 17px; height: 17px; margin-top: 3px; color: var(--primary); }

.dl-side { display: grid; gap: 20px; }

.qq-card { border-color: color-mix(in srgb, var(--primary) 42%, var(--border)); }

.qq-label { margin: 0; font-size: 13px; letter-spacing: 1.4px; color: var(--dim); }

.qq-num {
  margin: 6px 0 18px;
  font-family: var(--mono);
  font-size: 38px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--primary);
  user-select: all;
}

.qq-card .btn { width: 100%; }

.steps {
  margin: 20px 0 0;
  padding-left: 22px;
  display: grid;
  gap: 9px;
  font-size: 14px;
  color: var(--dim);
}

.steps li::marker { color: var(--primary); font-family: var(--mono); }

.qq-foot { margin: 18px 0 0; padding-top: 15px; border-top: 1px solid var(--border); font-size: 13px; color: var(--dim); }

.lite-card h3 { font-size: 16px; }

.lite-card p { margin-top: 9px; font-size: 14px; color: var(--dim); }

.soon {
  display: table;
  margin: 0 0 10px;
  padding: 2px 9px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--warning) 20%, transparent);
  color: var(--warning);
  font-size: 12.5px;
  font-weight: 700;
}

/* ───────────────────────────── 页脚 ───────────────────────────── */
.footer { padding: 58px 0 34px; border-top: 1px solid var(--border); background: var(--surface); }

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) repeat(2, minmax(0, 1fr));
  gap: 34px;
  padding-bottom: 30px;
}

.f-brand { display: flex; gap: 14px; }

.f-brand img { border-radius: 12px; }

.f-brand b { display: block; font-size: 16px; }

.f-brand p { margin-top: 6px; font-size: 13.4px; color: var(--dim); max-width: 30em; }

.f-col { display: grid; gap: 9px; align-content: start; }

.f-col h4 { margin-bottom: 6px; font-size: 13px; letter-spacing: 1.6px; color: var(--dim); }

.f-col a { font-size: 14px; color: var(--text); transition: color var(--t-fast) var(--ease-out); }

.f-col a:hover { color: var(--primary); }

.footer-bottom {
  display: grid;
  gap: 6px;
  padding-top: 22px;
  border-top: 1px solid var(--border);
  font-size: 12.6px;
  color: var(--dim);
}

/* ───────────────────────────── 进场动效 ───────────────────────────── */
.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--t-mid) var(--ease-out), transform var(--t-slow) var(--ease-back);
  transition-delay: var(--d, 0ms);
}

.js .reveal.in { opacity: 1; transform: none; }

.toast {
  position: fixed;
  left: 50%;
  bottom: 34px;
  z-index: 90;
  padding: 11px 20px;
  border: 1px solid var(--primary);
  border-radius: 11px;
  background: var(--surface);
  color: var(--text);
  font-size: 14px;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translate(-50%, 12px);
  transition: opacity var(--t-mid) var(--ease-out), transform var(--t-mid) var(--ease-back);
  pointer-events: none;
}

.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ───────────────────────────── 响应式 ───────────────────────────── */
@media (max-width: 1120px) {
  .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .theme-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stats { grid-template-columns: repeat(3, 1fr); row-gap: 18px; }
}

@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero { padding-top: 46px; }
  .only-wide { display: none; }
  .dl-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .f-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 2px;
    padding: 12px 20px 18px;
    border-bottom: 1px solid var(--border);
    background: var(--bg);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--t-mid) var(--ease-out), transform var(--t-mid) var(--ease-back),
                visibility var(--t-mid) linear;
  }

  .nav-links.open { transform: none; opacity: 1; visibility: visible; }

  .nav-links a { padding: 12px 10px; font-size: 16px; }

  .nav-burger { display: grid; }

  .section { padding: 78px 0; }
}

@media (max-width: 620px) {
  .wrap { padding: 0 18px; }
  .grid-4, .grid-3, .theme-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; margin-bottom: -34px; }
  .stat b { font-size: 25px; }
  .brand-text { display: none; }
  .nav-actions .btn { display: none; }
  .hero-cta .btn { width: 100%; }
  .qq-num { font-size: 30px; }
  .window-brand i { display: none; }
}

/* ───────────────────────────── 二级页通用 ───────────────────────────── */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
  border-radius: 6px;
}

.crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  font-size: 13px;
  color: var(--dim);
}

.crumb a:hover { color: var(--primary); }

.crumb span[aria-current] { color: var(--text); }

.page-head {
  position: relative;
  padding: 46px 0 38px;
  border-bottom: 1px solid var(--border);
  overflow: hidden;
}

.page-head::before {
  content: "";
  position: absolute;
  inset: -140px -140px auto auto;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  background: radial-gradient(circle, color-mix(in srgb, var(--primary) 22%, transparent), transparent 68%);
  pointer-events: none;
}

.page-head .wrap { position: relative; }

.page-head h1 { font-size: clamp(28px, 4vw, 42px); }

.page-head .lead {
  margin-top: 14px;
  max-width: 62ch;
  font-size: 16px;
  color: var(--dim);
}

.head-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }

.prose { max-width: 82ch; }

.prose h2 { font-size: 24px; margin: 0 0 12px; }

.prose h3 { font-size: 18px; margin: 26px 0 10px; }

.prose p { margin: 0 0 14px; font-size: 15.2px; color: var(--dim); }

.prose h3 + p, .prose h2 + p { color: var(--text); }

.prose ul, .prose ol { margin: 0 0 16px; padding-left: 22px; font-size: 15px; color: var(--dim); }

.prose li { margin-bottom: 7px; }

.prose li strong, .prose p strong { color: var(--text); }

.prose a { color: var(--primary); text-decoration: underline; text-underline-offset: 3px; }

.toc {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.toc a {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 11px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 14px;
  transition: border-color var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-back);
}

.toc a:hover { border-color: var(--primary); transform: translateX(3px); }

.toc .ic { width: 16px; height: 16px; color: var(--primary); }

.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.section-tight { padding: 56px 0; }

pre.code {
  margin: 18px 0 24px;
  padding: 18px 20px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  overflow-x: auto;
}

pre.code code {
  display: block;
  overflow-wrap: normal;
  background: none;
  padding: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--text);
}

/* 功能详解条目 */
.feat {
  display: grid;
  grid-template-columns: 268px minmax(0, 1fr);
  gap: 36px;
  padding: 42px 0;
  border-top: 1px solid var(--border);
  scroll-margin-top: 90px;
}

.feat:first-of-type { border-top: 0; padding-top: 8px; }

.feat-side { position: sticky; top: calc(var(--nav-h) + 22px); align-self: start; }

.feat-side .card-ic { margin-bottom: 12px; }

.feat-side h2 { font-size: 23px; }

.feat-side .en {
  margin: 4px 0 12px;
  font-size: 11.5px;
  letter-spacing: 1.7px;
  color: var(--dim);
  text-transform: uppercase;
}

.feat-side .no {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--primary);
}

.feat-body p { font-size: 15.2px; color: var(--dim); margin-bottom: 16px; }

.feat-body > p:first-child { color: var(--text); }

.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0 0; padding: 0; list-style: none; }

.chip {
  padding: 4px 11px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  font-size: 12.5px;
  color: var(--dim);
}

.callout {
  display: flex;
  gap: 12px;
  margin: 22px 0 0;
  padding: 16px 18px;
  border: 1px solid color-mix(in srgb, var(--primary) 34%, var(--border));
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--primary) 8%, transparent);
  font-size: 14.2px;
  color: var(--dim);
}

.callout .ic { width: 18px; height: 18px; margin-top: 3px; color: var(--primary); flex: none; }

.callout strong { color: var(--text); }

/* 步骤 */
.steps-lg {
  counter-reset: step;
  display: grid;
  gap: 14px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.steps-lg > li {
  counter-increment: step;
  position: relative;
  padding: 18px 20px 18px 62px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-size: 14.6px;
  color: var(--dim);
}

.steps-lg > li::before {
  content: counter(step);
  position: absolute;
  left: 19px;
  top: 17px;
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: color-mix(in srgb, var(--primary) 18%, transparent);
  color: var(--primary);
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 700;
}

.steps-lg strong { display: block; margin-bottom: 3px; color: var(--text); font-size: 15.4px; }

/* 表格化的信息块 */
.kv { margin: 0; display: grid; gap: 0; }

.kv > div {
  display: grid;
  grid-template-columns: 132px minmax(0, 1fr);
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid var(--border);
}

.kv > div:last-child { border-bottom: 0; }

.kv dt { font-size: 13.4px; color: var(--dim); }

.kv dd { margin: 0; font-size: 14.4px; }

/* 可点的卡片 */
a.card { display: block; position: relative; padding-bottom: 52px; }

a.card .go {
  position: absolute;
  left: 24px;
  bottom: 20px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 13.4px;
  font-weight: 700;
  color: var(--primary);
}

a.card .go .ic { width: 15px; height: 15px; transition: transform var(--t-fast) var(--ease-back); }

a.card:hover .go .ic { transform: translateX(4px); }

/* ───────────────────────────── 主题页 ───────────────────────────── */
.filter-bar { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 26px; }

.filter {
  padding: 7px 15px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--dim);
  font-family: inherit;
  font-size: 13.5px;
  cursor: pointer;
  transition: color var(--t-fast) var(--ease-out), border-color var(--t-fast) var(--ease-out),
              background var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-back);
}

.filter:hover { color: var(--text); border-color: var(--primary); transform: translateY(-1px); }

.filter.active {
  background: var(--primary);
  border-color: var(--primary);
  color: var(--on-primary);
  font-weight: 700;
}

.theme-card.hide { display: none; }

.theme-meta { position: relative; }

.theme-meta b { margin-right: auto; }

.theme-dot {
  flex: none;
  width: 11px;
  height: 11px;
  border: 1px solid var(--border);
  border-radius: 50%;
}

.theme-card .kind {
  position: absolute;
  top: 10px;
  left: 10px;
  padding: 2px 8px;
  border-radius: 7px;
  background: color-mix(in srgb, #05080c 62%, transparent);
  color: #fff;
  font-size: 11px;
  letter-spacing: .4px;
}

.theme-card code { position: relative; z-index: 1; }

/* ───────────────────────────── 实拍截图卡片 ───────────────────────────── */
.shot {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: 0 10px 26px rgba(0, 0, 0, .2);
  transition: transform var(--t-mid) var(--ease-back), border-color var(--t-fast) var(--ease-out),
              box-shadow var(--t-mid) var(--ease-out);
}

.shot:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--primary) 55%, var(--border));
  box-shadow: 0 18px 38px rgba(0, 0, 0, .3);
}

.shot img { width: 100%; height: auto; display: block; }

.shot figcaption {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 14px;
  padding: 13px 17px;
  border-top: 1px solid var(--border);
  font-size: 12.8px;
  color: var(--dim);
}

.shot figcaption b { font-size: 15px; color: var(--text); }

.shot-grid { margin-top: 4px; }

.demo-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }

.demo {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 8px 14px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--dim);
}

.demo::after {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
  transition: transform var(--t-fast) var(--ease-back);
}

.demo:hover::after { transform: translateX(12px); }

.demo-mid::after { transition-duration: var(--t-mid); }
.demo-slow::after { transition-duration: var(--t-slow); }

/* ───────────────────────────── FAQ ───────────────────────────── */
.faq { display: grid; gap: 12px; }

.faq details {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  transition: border-color var(--t-fast) var(--ease-out);
}

.faq details[open] { border-color: color-mix(in srgb, var(--primary) 45%, var(--border)); }

.faq summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 17px 20px;
  font-size: 15.4px;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
}

.faq summary::-webkit-details-marker { display: none; }

.faq summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--mono);
  font-size: 19px;
  color: var(--primary);
  transition: transform var(--t-mid) var(--ease-back);
}

.faq details[open] summary::after { transform: rotate(45deg); }

.faq .ans {
  padding: 0 20px 19px;
  font-size: 14.6px;
  color: var(--dim);
}

.faq .ans p { margin-bottom: 10px; }

.faq .ans p:last-child { margin-bottom: 0; }

/* ───────────────────────────── 收尾 CTA ───────────────────────────── */
.cta-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-top: 62px;
  padding: 30px 32px;
  border: 1px solid color-mix(in srgb, var(--primary) 38%, var(--border));
  border-radius: var(--radius);
  background: linear-gradient(135deg, color-mix(in srgb, var(--primary) 14%, var(--surface)), var(--surface));
}

.cta-strip h3 { font-size: 21px; }

.cta-strip p { margin-top: 6px; font-size: 14.4px; color: var(--dim); }

/* ───────────────────────────── 回到顶部 / 手机标签栏 ───────────────────────────── */
.to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 60;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  box-shadow: var(--shadow);
  transition: opacity var(--t-mid) var(--ease-out), transform var(--t-mid) var(--ease-back),
              border-color var(--t-fast) var(--ease-out);
}

.to-top.show { opacity: 1; transform: none; pointer-events: auto; }

.to-top:hover { border-color: var(--primary); }

.to-top .ic { width: 19px; height: 19px; }

.tabbar { display: none; }

/* ───────────────────────────── 404 ───────────────────────────── */
.nf { padding: 96px 0 120px; text-align: center; }

.nf-code {
  font-family: var(--mono);
  font-size: clamp(64px, 14vw, 128px);
  font-weight: 700;
  line-height: 1;
  color: color-mix(in srgb, var(--primary) 40%, transparent);
}

.nf h1 { font-size: clamp(22px, 4vw, 32px); margin-top: 10px; }

.nf-lead { margin: 14px auto 28px; max-width: 40ch; font-size: 15px; color: var(--dim); }

.nf-links { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }

/* ───────────────────────────── 触控细节 ───────────────────────────── */
a, button { -webkit-tap-highlight-color: transparent; }

/* ───────────────────────────── 响应式补充 ───────────────────────────── */
@media (max-width: 1120px) {
  .toc { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 960px) {
  .feat { grid-template-columns: 1fr; gap: 18px; padding: 34px 0; }
  .feat-side { position: static; }
  .grid-2 { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .section { padding: 56px 0; }
  .sec-head { margin-bottom: 28px; }
  .page-head { padding: 30px 0 26px; }
  .page-head::before { display: none; }
  .toc { grid-template-columns: 1fr; }
  .kv > div { grid-template-columns: 1fr; gap: 3px; }
  .cta-strip { flex-direction: column; align-items: stretch; text-align: center; }
  .dl-grid { gap: 16px; }
}

@media (max-width: 620px) {
  :root { --nav-h: 60px; }

  body { padding-bottom: calc(62px + env(safe-area-inset-bottom)); }

  .tabbar {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 70;
    padding-bottom: env(safe-area-inset-bottom);
    border-top: 1px solid var(--border);
    background: color-mix(in srgb, var(--bg) 92%, transparent);
    backdrop-filter: blur(14px) saturate(160%);
  }

  .tabbar a {
    display: grid;
    justify-items: center;
    gap: 3px;
    padding: 9px 2px 8px;
    font-size: 11px;
    color: var(--dim);
    min-height: 50px;
    transition: color var(--t-fast) var(--ease-out), background var(--t-fast) var(--ease-out);
  }

  .tabbar a:active { background: var(--surface); }

  .tabbar a.active { color: var(--primary); font-weight: 700; }

  .tabbar .ic { width: 21px; height: 21px; }

  .to-top { bottom: calc(74px + env(safe-area-inset-bottom)); right: 14px; }

  .hero { padding-top: 30px; }

  .hero h1 { font-size: 34px; }

  .hero-en { font-size: 17px; letter-spacing: 2.4px; }

  .hero-lead { font-size: 15.4px; }

  .hero-inner { gap: 30px; padding-bottom: 40px; }

  .stats { gap: 10px 14px; padding: 18px; margin-bottom: -26px; }

  .stat { align-items: flex-start; gap: 8px; }

  .stat b { font-size: 22px; }

  .card { padding: 22px 20px; }

  .card-lg { padding: 24px 22px; }

  .tag { position: static; display: inline-block; margin-bottom: 12px; }

  .card-lg .card-ic { margin-bottom: 12px; }

  .window-bar { height: 44px; padding: 0 12px; }

  .qq-num { font-size: 27px; letter-spacing: 1px; }

  .dl-card, .qq-card, .lite-card { padding: 22px 20px 24px; }

  .steps-lg > li { padding: 16px 16px 16px 52px; }

  .steps-lg > li::before { left: 14px; top: 15px; }

  .faq summary { padding: 15px 16px; font-size: 14.6px; }

  .faq .ans { padding: 0 16px 16px; font-size: 14px; }

  .mock-body { grid-template-columns: 54px minmax(0, 1fr); }

  .footer { padding: 40px 0 30px; }

  .footer-grid { grid-template-columns: 1fr; gap: 24px; }

  .icon-btn { width: 42px; height: 42px; }

  .nav-links a { padding: 13px 10px; min-height: 44px; }

  .filter { padding: 9px 15px; min-height: 40px; }

  .theme-meta { padding: 12px 13px; }

  .loader { padding: 8px 12px 8px 8px; }

  .nf { padding: 54px 0 76px; }

  .nf-links .btn { width: 100%; }

  .head-actions { flex-direction: column; align-items: stretch; }

  .head-actions .btn { width: 100%; }

  pre.code { padding: 14px 15px; }

  pre.code code { font-size: 11.6px; line-height: 1.68; }

  .toc a { padding: 13px 14px; }

  .crumb { font-size: 12.5px; }

  .demo-row .demo { flex: 1 1 auto; justify-content: center; }
}

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