/* =========================================================================
   彩虹边框 RainbowBorder · 落地页样式
   设计基调：深色陈列室。页面本身就是一个"边框标本"，主色随所选主题整页联动。
   性能约定：边框流动只用 transform（合成层），不触发重绘。
   ========================================================================= */

/* ------------------------------------------------------------------ 基础 */

*, *::before, *::after { box-sizing: border-box; }

:root {
  --bg: #090a0e;
  --bg-soft: #0e1016;
  --surface: #151924;
  --surface-2: #1b2130;
  --line: rgba(255, 255, 255, .09);
  --line-strong: rgba(255, 255, 255, .18);
  --text: #e9ecf3;
  --text-dim: #97a1b3;
  --text-faint: #6c7688;

  --wrap: 1120px;
  --radius: 14px;

  /* 预览窗口的圆角与描边粗细（对应软件设置项） */
  --win-radius: 14px;
  --thickness: 4px;
  --spin: 7s;

  /* 以下 4 个由各主题块覆盖；这里给的是彩虹主题的兜底值 */
  --pad-win: 30px;
  --accent: #7c5cff;
  --accent-text: #a78bfa;
  --a1: #ff3b30;
  --a2: #3b6bff;
  --g1: #ff3b30; --g2: #ffc300; --g3: #34c759;
  --g4: #00c2d1; --g5: #3b6bff; --g6: #b44bff;
}

/* ---- 8 款主题的调色板（与桌面版 themes/*.py 一一对应）---- */

[data-theme="rainbow"] {
  --pad-win: 26px;
  --accent: #7c5cff; --accent-text: #a78bfa; --a1: #ff3b30; --a2: #3b6bff;
  --g1: #ff3b30; --g2: #ffc300; --g3: #34c759; --g4: #00c2d1; --g5: #3b6bff; --g6: #b44bff;
}
[data-theme="halloween"] {
  --pad-win: 36px;
  --accent: #c2571a; --accent-text: #ffb86b; --a1: #ff7a1a; --a2: #a855f7;
  --g1: #ff7a1a; --g2: #a855f7; --g3: #22c55e; --g4: #f59e0b; --g5: #7c3aed; --g6: #ff7a1a;
}
[data-theme="national_day"] {
  --pad-win: 34px;
  --accent: #c0201a; --accent-text: #ffd166; --a1: #d6261e; --a2: #ffcd46;
  --g1: #d6261e; --g2: #ffcd46; --g3: #9e1612; --g4: #ffcd46; --g5: #c0201a; --g6: #d6261e;
}
[data-theme="mid_autumn"] {
  --pad-win: 38px;
  --accent: #2f4a7d; --accent-text: #f0d9a0; --a1: #ffd98a; --a2: #3a5284;
  --g1: #1b2a4a; --g2: #ffd98a; --g3: #3a5284; --g4: #a8bee6; --g5: #233459; --g6: #1b2a4a;
}
[data-theme="new_year"] {
  --pad-win: 40px;
  --accent: #c81f18; --accent-text: #ffd166; --a1: #e83a2e; --a2: #ffd25e;
  --g1: #9e1410; --g2: #ffd25e; --g3: #e83a2e; --g4: #ffd25e; --g5: #b81612; --g6: #9e1410;
}
[data-theme="valentine"] {
  --pad-win: 32px;
  --accent: #e0285f; --accent-text: #ff8fb0; --a1: #ff3d7f; --a2: #ff8fb0;
  --g1: #ff3d7f; --g2: #ffc2d4; --g3: #ff6f91; --g4: #ffc2d4; --g5: #e0285f; --g6: #ff3d7f;
}
[data-theme="qixi"] {
  --pad-win: 38px;
  --accent: #6d54d8; --accent-text: #b9a6ff; --a1: #8b6cf0; --a2: #a8d8ff;
  --g1: #241b4a; --g2: #8b6cf0; --g3: #42588e; --g4: #a8d8ff; --g5: #2e2460; --g6: #241b4a;
}
[data-theme="christmas"] {
  --pad-win: 38px;
  --accent: #1e7a46; --accent-text: #86e0a8; --a1: #d62828; --a2: #1e7a46;
  --g1: #1e7a46; --g2: #f2c14e; --g3: #d62828; --g4: #eef6ff; --g5: #14603a; --g6: #1e7a46;
}

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI Variable Text", "Segoe UI", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* 背景：两团主题色柔光，纯静态，不参与动画 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(760px 520px at 12% -6%, color-mix(in oklab, var(--a1) 18%, transparent), transparent 62%),
    radial-gradient(620px 460px at 96% 8%, color-mix(in oklab, var(--a2) 16%, transparent), transparent 60%);
  transition: background .6s ease;
  pointer-events: none;
}

h1, h2, h3 { margin: 0; font-weight: 700; line-height: 1.15; letter-spacing: -.02em; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
code { font-family: "Cascadia Mono", "JetBrains Mono", ui-monospace, Consolas, monospace; font-size: .92em; }

kbd {
  font-family: "Cascadia Mono", ui-monospace, monospace;
  font-size: .8rem;
  padding: .18em .5em;
  border-radius: 6px;
  border: 1px solid var(--line-strong);
  background: var(--surface-2);
  color: var(--text);
}

::selection { background: color-mix(in oklab, var(--accent) 45%, transparent); }

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

.skip-link {
  position: absolute; left: 12px; top: -60px;
  z-index: 100;
  padding: 10px 16px;
  background: var(--surface-2);
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  transition: top .2s;
}
.skip-link:focus { top: 12px; }

.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.wrap--narrow { max-width: 760px; }

/* ------------------------------------------------------------ 通用组件 */

.btn {
  display: inline-flex;
  align-items: center;
  gap: .5em;
  padding: .68em 1.25em;
  border-radius: 999px;
  border: 1px solid color-mix(in oklab, var(--accent) 55%, transparent);
  background: color-mix(in oklab, var(--accent) 16%, transparent);
  color: var(--text);
  font-size: .95rem;
  font-weight: 600;
  white-space: nowrap;
  cursor: pointer;
  transition: background .18s ease, border-color .18s ease, transform .18s ease;
}
.btn:hover { background: color-mix(in oklab, var(--accent) 30%, transparent); border-color: color-mix(in oklab, var(--accent) 80%, transparent); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn--sm { padding: .5em 1em; font-size: .875rem; }
.btn--lg { padding: .82em 1.6em; font-size: 1.05rem; }
.btn--block { width: 100%; justify-content: center; }
.btn--ghost { background: transparent; border-color: var(--line-strong); }
.btn--ghost:hover { background: rgba(255, 255, 255, .05); border-color: var(--line-strong); }
.btn__price { font-variant-numeric: tabular-nums; opacity: .85; }

.eyebrow {
  display: inline-flex; align-items: center; gap: .55em;
  font-size: .82rem; font-weight: 600; letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--accent-text);
}
.eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent-text);
  box-shadow: 0 0 0 4px color-mix(in oklab, var(--accent) 22%, transparent);
}

/* ------------------------------------------------------------ 顶部导航 */

.nav {
  position: sticky; top: 0; z-index: 30;
  border-bottom: 1px solid transparent;
  transition: background .25s ease, border-color .25s ease, backdrop-filter .25s ease;
}
.nav.is-stuck {
  background: color-mix(in oklab, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom-color: var(--line);
}
.nav__inner { display: flex; align-items: center; gap: 24px; height: 66px; }

.brand { display: flex; align-items: baseline; gap: 8px; font-weight: 700; letter-spacing: -.01em; }
.brand__mark {
  width: 15px; height: 15px; border-radius: 5px;
  align-self: center;
  background: conic-gradient(from 210deg, var(--g1), var(--g2), var(--g3), var(--g4), var(--g5), var(--g6), var(--g1));
  box-shadow: 0 0 14px color-mix(in oklab, var(--accent) 55%, transparent);
  transition: box-shadow .4s ease;
}
.brand__name { font-size: 1rem; }
.brand__sub { font-size: .76rem; color: var(--text-faint); font-weight: 500; letter-spacing: .04em; }

.nav__links { display: flex; gap: 26px; margin-left: auto; font-size: .92rem; color: var(--text-dim); }
.nav__links a { padding: 4px 0; border-bottom: 1px solid transparent; transition: color .18s, border-color .18s; }
.nav__links a:hover { color: var(--text); border-bottom-color: var(--accent-text); }

/* ------------------------------------------------------------ 首屏 */

.hero { padding: clamp(48px, 7vw, 90px) 0 clamp(40px, 5vw, 64px); }
.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
  gap: clamp(36px, 5vw, 68px);
  align-items: center;
}

.hero__copy h1 {
  margin: 18px 0 0;
  font-size: clamp(2.05rem, 1.15rem + 3.4vw, 3.5rem);
}
.hero__copy h1 em {
  font-style: normal;
  color: var(--accent-text);
  position: relative;
}
.hero__copy h1 em::after {
  content: "";
  position: absolute; left: 0; right: 0; bottom: -.06em;
  height: 3px;
  border-radius: 2px;
  background: conic-gradient(from 200deg, var(--g1), var(--g3), var(--g5), var(--g1));
  opacity: .85;
}

.lead { margin-top: 20px; font-size: clamp(1rem, .95rem + .3vw, 1.12rem); color: var(--text-dim); max-width: 30em; }

.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }

.hero__meta { display: flex; flex-wrap: wrap; gap: 10px 22px; margin-top: 26px; font-size: .86rem; color: var(--text-faint); }
.hero__meta li { position: relative; padding-left: 16px; }
.hero__meta li::before {
  content: ""; position: absolute; left: 0; top: .6em;
  width: 5px; height: 5px; border-radius: 50%;
  background: var(--accent-text);
}

/* ------------------------------------------------------------ 预览窗口 */

.stage {
  position: relative;
  padding: var(--pad-win);
  transition: padding .35s ease;
}

.win {
  position: relative;
  border-radius: var(--win-radius);
  background: var(--surface);
  box-shadow: 0 26px 60px -30px rgba(0, 0, 0, .9);
}

.win--preview { min-height: 232px; }

.win__bar {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 14px;
  border-bottom: 1px solid var(--line);
}
.win__dots { display: inline-flex; gap: 6px; }
.win__dots i { width: 9px; height: 9px; border-radius: 50%; background: var(--surface-2); border: 1px solid var(--line-strong); }
.win__title { font-size: .8rem; color: var(--text-faint); letter-spacing: .01em; }

.win__body { padding: 20px 18px 26px; }

.skel { height: 9px; border-radius: 5px; background: var(--surface-2); margin-bottom: 11px; }
.skel--w45 { width: 45%; }
.skel--w50 { width: 50%; }
.skel--w60 { width: 60%; }
.skel--w70 { width: 70%; }
.skel--w75 { width: 75%; }
.skel--w90 { width: 90%; }

/* ---- 边框引擎：外层遮罩出"环"，内层圆锥渐变只做 transform 旋转 ---- */

.bd {
  position: absolute;
  inset: calc(-1 * var(--pad-win));
  pointer-events: none;
  z-index: 3;
}

.bd__glow {
  position: absolute;
  inset: calc(var(--pad-win) - 2px);
  border-radius: calc(var(--win-radius) + 2px);
  background: linear-gradient(115deg, var(--a1), var(--a2));
  filter: blur(22px);
  opacity: .42;
  transition: opacity .5s ease;
}

.bd__ring {
  position: absolute;
  inset: var(--pad-win);
  border-radius: var(--win-radius);
  padding: var(--thickness);
  overflow: hidden;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
}

.bd__spin {
  position: absolute;
  left: -80%; top: -80%;
  width: 260%; height: 260%;
  background: conic-gradient(from 0deg,
    var(--g1) 0deg, var(--g2) 60deg, var(--g3) 120deg,
    var(--g4) 180deg, var(--g5) 240deg, var(--g6) 300deg, var(--g1) 360deg);
  will-change: transform;
  animation: bd-spin var(--spin) linear infinite;
}
@keyframes bd-spin { to { transform: rotate(360deg); } }

/* ---- 主题装饰 ---- */

.decor {
  position: absolute;
  inset: calc(-1 * var(--pad-win));
  pointer-events: none;
  z-index: 4;
}
.slot { position: absolute; width: 0; height: 0; }
.slot--tl { left: var(--pad-win); top: var(--pad-win); }
.slot--tr { right: var(--pad-win); top: var(--pad-win); }
.slot--bl { left: var(--pad-win); bottom: var(--pad-win); }
.slot--br { right: var(--pad-win); bottom: var(--pad-win); }
.slot--top { left: 50%; top: var(--pad-win); }
.slot--top-l { left: 30%; top: var(--pad-win); }
.slot--top-r { left: 70%; top: var(--pad-win); }
.slot--bottom { left: 50%; bottom: var(--pad-win); }

.icon {
  position: absolute; left: 0; top: 0;
  width: var(--isz, 26px); height: var(--isz, 26px);
  transform: translate(-50%, -50%);
  color: var(--accent-text);
  filter: drop-shadow(0 2px 8px rgba(0, 0, 0, .55));
}
.icon svg { width: 100%; height: 100%; display: block; }

.icon--spin { animation: icon-spin 9s linear infinite; }
.icon--pulse { animation: icon-pulse 2.4s ease-in-out infinite; }
.icon--sway { animation: icon-sway 3.6s ease-in-out infinite; }

@keyframes icon-spin { from { transform: translate(-50%, -50%) rotate(0); } to { transform: translate(-50%, -50%) rotate(360deg); } }
@keyframes icon-pulse { 0%, 100% { transform: translate(-50%, -50%) scale(1); } 50% { transform: translate(-50%, -50%) scale(1.18); } }
@keyframes icon-sway { 0%, 100% { transform: translate(-50%, -50%) rotate(-9deg); } 50% { transform: translate(-50%, -50%) rotate(9deg); } }

/* 银河光带（七夕） */
.galaxy {
  position: absolute;
  left: 50%; top: var(--pad-win);
  width: min(64%, 420px); height: 30px;
  transform: translate(-50%, -46%);
  border-radius: 50%;
  background: radial-gradient(ellipse at center,
    color-mix(in oklab, var(--accent) 75%, transparent), transparent 72%);
  filter: blur(7px);
  animation: icon-pulse 4.5s ease-in-out infinite;
}

/* ------------------------------------------------------------ 主题选择器 */

.chips {
  display: flex; flex-wrap: wrap; gap: 8px;
  margin-top: 22px;
  padding: 0 var(--pad-win);
}
.chips--center { justify-content: center; padding: 0; margin-top: 26px; }

.chip {
  display: inline-flex; align-items: center; gap: 7px;
  padding: .42em .8em;
  font: inherit; font-size: .82rem;
  color: var(--text-dim);
  background: rgba(255, 255, 255, .03);
  border: 1px solid var(--line);
  border-radius: 999px;
  cursor: pointer;
  transition: color .16s, border-color .16s, background .16s;
}
.chip__dot {
  width: 12px; height: 12px; border-radius: 4px;
  background: conic-gradient(from 200deg, var(--g1), var(--g2), var(--g3), var(--g4), var(--g5), var(--g1));
}
.chip:hover { color: var(--text); border-color: var(--line-strong); background: rgba(255, 255, 255, .06); }
.chip[aria-pressed="true"] {
  color: var(--text);
  border-color: color-mix(in oklab, var(--accent) 70%, transparent);
  background: color-mix(in oklab, var(--accent) 20%, transparent);
}

/* ------------------------------------------------------------ 区块与卡片 */

.section { padding: clamp(56px, 7vw, 96px) 0; }
.section__head { max-width: 44em; margin-bottom: clamp(32px, 4vw, 52px); }
.section__head h2 { margin-top: 14px; font-size: clamp(1.55rem, 1.1rem + 2vw, 2.3rem); }
.section__lead { margin-top: 16px; color: var(--text-dim); max-width: 34em; }

.grid--4 { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 18px; }

.card {
  position: relative;
  padding: 26px 22px 28px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(255, 255, 255, .035), rgba(255, 255, 255, .012));
  transition: border-color .2s ease, transform .2s ease;
}
.card:hover { border-color: color-mix(in oklab, var(--accent) 45%, transparent); transform: translateY(-3px); }
.card__num {
  display: block;
  font-family: "Cascadia Mono", ui-monospace, monospace;
  font-size: .78rem; letter-spacing: .12em;
  color: var(--accent-text);
  opacity: .9;
  margin-bottom: 14px;
}
.card h3 { font-size: 1.06rem; margin-bottom: 9px; }
.card p { font-size: .92rem; color: var(--text-dim); }

/* ------------------------------------------------------------ 数据条 */

.perf { padding: 8px 0 clamp(48px, 6vw, 76px); }
.perf__grid {
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line);
}
.perf__item { padding: 24px 22px; background: var(--bg-soft); }
.perf__item dt { font-size: .82rem; color: var(--text-faint); }
.perf__item dd {
  margin: 6px 0 8px;
  display: flex; align-items: baseline; gap: 4px;
  color: var(--text);
}
.num {
  font-family: "Cascadia Mono", ui-monospace, monospace;
  font-size: clamp(1.5rem, 1.1rem + 1.4vw, 2rem);
  font-weight: 600;
  letter-spacing: -.02em;
  font-variant-numeric: tabular-nums;
}
.unit { font-size: .85rem; color: var(--text-faint); }
.perf__item p { font-size: .8rem; color: var(--text-faint); }

/* ------------------------------------------------------------ 拖动试看 */

.section--demo { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--bg-soft); }

.demo {
  position: relative;
  height: clamp(330px, 44vh, 430px);
  border-radius: 20px;
  border: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, .028), transparent 70%),
    repeating-linear-gradient(90deg, var(--line) 0 1px, transparent 1px 46px),
    repeating-linear-gradient(0deg, var(--line) 0 1px, transparent 1px 46px);
  background-blend-mode: normal;
  overflow: hidden;
  touch-action: none;
}

.win--drag {
  position: absolute;
  left: 50%; top: 50%;
  width: min(430px, 76%);
  transform: translate(calc(-50% + var(--dx, 0px)), calc(-50% + var(--dy, 0px)));
  cursor: grab;
  will-change: transform;
}
.win--drag:active, .win--drag.is-dragging { cursor: grabbing; }
.win--drag:focus-visible { outline-offset: 6px; }

.demo__hint { font-size: .82rem; color: var(--text-faint); margin-bottom: 14px; }
.demo__note { margin-top: 20px; text-align: center; font-size: .84rem; color: var(--text-faint); }

/* ------------------------------------------------------------ 使用方式 */

.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.step {
  position: relative;
  padding: 24px 22px;
  border-left: 2px solid color-mix(in oklab, var(--accent) 45%, transparent);
  background: linear-gradient(90deg, rgba(255, 255, 255, .03), transparent);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.step__idx {
  display: inline-flex; align-items: center; justify-content: center;
  width: 26px; height: 26px;
  margin-bottom: 12px;
  border-radius: 50%;
  font-size: .8rem; font-weight: 700;
  color: var(--bg);
  background: var(--accent-text);
}
.step h3 { font-size: 1rem; margin-bottom: 8px; }
.step p { font-size: .9rem; color: var(--text-dim); }

.keys {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px;
  margin-top: 30px;
  padding: 18px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, .02);
}
.keys__label { font-size: .82rem; color: var(--accent-text); font-weight: 600; margin-right: 6px; }
.keys__plus { color: var(--text-faint); font-size: .8rem; }
.keys__desc { font-size: .82rem; color: var(--text-faint); margin: 0 18px 0 6px; }

/* ------------------------------------------------------------ 价格 */

.price {
  display: grid;
  grid-template-columns: minmax(0, 340px) minmax(0, 1fr);
  gap: clamp(20px, 3vw, 40px);
  align-items: start;
}
.price__main {
  padding: 30px 26px;
  border-radius: var(--radius);
  border: 1px solid color-mix(in oklab, var(--accent) 45%, transparent);
  background: linear-gradient(180deg, color-mix(in oklab, var(--accent) 12%, transparent), rgba(255, 255, 255, .015));
}
.price__tag { font-size: .82rem; color: var(--accent-text); font-weight: 600; }
.price__amount { display: flex; align-items: baseline; gap: 6px; margin: 12px 0 4px; }
.price__cur { font-size: 1.4rem; color: var(--text-dim); }
.price__num {
  font-family: "Cascadia Mono", ui-monospace, monospace;
  font-size: 3.4rem; font-weight: 700; line-height: 1;
  letter-spacing: -.03em;
  font-variant-numeric: tabular-nums;
}
.price__was { color: var(--text-faint); font-size: 1rem; margin-left: 6px; }
.price__note { font-size: .84rem; color: var(--text-faint); margin-bottom: 22px; }
.price__fine { margin-top: 14px; font-size: .76rem; color: var(--text-faint); line-height: 1.6; }

.price__list { display: grid; gap: 12px; padding-top: 6px; }
.price__list li {
  position: relative;
  padding-left: 28px;
  font-size: .95rem;
  color: var(--text-dim);
}
.price__list li::before {
  content: "";
  position: absolute; left: 0; top: .42em;
  width: 14px; height: 8px;
  border-left: 2px solid var(--accent-text);
  border-bottom: 2px solid var(--accent-text);
  transform: rotate(-45deg);
}

/* ------------------------------------------------------------ 购买 */

.section--buy { border-top: 1px solid var(--line); background: var(--bg-soft); }
.buy {
  display: grid;
  grid-template-columns: minmax(0, 300px) minmax(0, 1fr);
  gap: clamp(24px, 4vw, 52px);
  align-items: center;
}

.buy__side {
  display: grid;
  gap: 10px;
  justify-items: center;
  padding: 30px 26px;
  border-radius: var(--radius);
  border: 1px solid color-mix(in oklab, var(--accent) 45%, transparent);
  background: linear-gradient(180deg, color-mix(in oklab, var(--accent) 12%, transparent), rgba(255, 255, 255, .015));
}
.buy__price {
  display: flex; align-items: baseline; gap: 4px;
  font-family: "Cascadia Mono", ui-monospace, monospace;
  font-size: 3.4rem; font-weight: 700; line-height: 1;
  letter-spacing: -.03em;
  font-variant-numeric: tabular-nums;
}
.buy__cur { font-size: 1.4rem; color: var(--text-dim); }
.buy__note { font-size: .86rem; color: var(--text-faint); margin-bottom: 14px; }
.buy__side .btn { width: 100%; }
.buy__fine { margin-top: 14px; font-size: .76rem; color: var(--text-faint); line-height: 1.6; text-align: left; }

.buy__steps { display: grid; gap: 22px; }
.buy__steps li { display: flex; gap: 16px; align-items: flex-start; }
.buy__steps h3 { font-size: 1rem; margin-bottom: 6px; }
.buy__steps p { font-size: .92rem; color: var(--text-dim); }

/* ------------------------------------------------------------ FAQ */

.faq { display: grid; gap: 10px; }
.faq__item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, .018);
  overflow: hidden;
}
.faq__item summary {
  padding: 18px 22px;
  font-weight: 600;
  font-size: .98rem;
  cursor: pointer;
  list-style: none;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after {
  content: "";
  flex: none;
  width: 9px; height: 9px;
  border-right: 2px solid var(--accent-text);
  border-bottom: 2px solid var(--accent-text);
  transform: rotate(45deg) translate(-2px, -2px);
  transition: transform .2s ease;
}
.faq__item[open] summary::after { transform: rotate(-135deg) translate(-2px, -2px); }
.faq__item p { padding: 0 22px 20px; font-size: .92rem; color: var(--text-dim); }

/* ------------------------------------------------------------ 结尾与页脚 */

.finale { padding: clamp(64px, 8vw, 104px) 0; text-align: center; }
.finale h2 { font-size: clamp(1.6rem, 1.1rem + 2.2vw, 2.5rem); margin-bottom: 28px; }

.footer { border-top: 1px solid var(--line); padding: 32px 0 44px; }
.footer__inner { display: grid; gap: 6px; text-align: center; font-size: .82rem; color: var(--text-faint); }
.footer__brand { color: var(--text-dim); font-weight: 600; }
.footer__brand span { color: var(--text-faint); font-weight: 400; }

/* ------------------------------------------------------------ 滚动入场 */

.reveal { opacity: 0; transform: translateY(14px); transition: opacity .55s ease, transform .55s ease; }
.reveal.is-in { opacity: 1; transform: none; }

/* ------------------------------------------------------------ 响应式 */

@media (max-width: 1000px) {
  .hero__grid { grid-template-columns: minmax(0, 1fr); }
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .perf__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .price { grid-template-columns: minmax(0, 1fr); }
  .buy { grid-template-columns: minmax(0, 1fr); }
  .nav__links { display: none; }
  .brand__sub { display: none; }
}

@media (max-width: 640px) {
  .wrap { padding: 0 18px; }
  .grid--4, .steps { grid-template-columns: minmax(0, 1fr); }
  .stage { padding: calc(var(--pad-win) * .8); }
  .demo { height: 360px; }
  .win--drag { width: 82%; }
  .buy__side { padding: 24px 18px; }
  .keys__desc { margin-right: 10px; }
}

/* ------------------------------------------------------------ 无障碍：降低动效 */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .bd__spin, .icon, .galaxy { animation: none !important; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .btn:hover, .card:hover { transform: none; }
  * { transition-duration: .01ms !important; }
}