@charset "utf-8";
/* ==========================================================================
   Vorssaint 官网样式
   单色体系，取自品牌标识（墨黑行星 + 中性灰），扁平、明亮、无渐变装饰
   ========================================================================== */

:root {
  --ink: #0a0a0b;
  --ink-2: #212225;
  --text: #1f2124;
  --muted: #5f636a;
  --muted-2: #8a8e95;
  --line: #e6e6e8;
  --line-2: #d3d4d7;
  --paper: #ffffff;
  --surface: #f7f7f8;
  --surface-2: #f1f1f2;
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 8px;
  --maxw: 1120px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --shadow-1: 0 1px 2px rgba(10, 10, 11, .05);
  --shadow-2: 0 22px 48px -30px rgba(10, 10, 11, .45);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; }
a { color: inherit; }

h1, h2, h3, h4 {
  margin: 0;
  font-weight: 700;
  letter-spacing: -.015em;
  line-height: 1.25;
  color: var(--ink);
}

p { margin: 0; }
ul, ol { margin: 0; padding: 0; }
code, pre { font-family: var(--mono); }

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

::selection { background: var(--ink); color: #fff; }

.svg-sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

.ic {
  width: 1.2em;
  height: 1.2em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex: none;
  vertical-align: -.2em;
}

.skip {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 100;
  background: var(--ink);
  color: #fff;
  padding: 10px 16px;
  border-radius: var(--radius-xs);
  text-decoration: none;
  font-size: 14px;
  transition: top .18s ease;
}
.skip:focus { top: 12px; }

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

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 48px;
  padding: 0 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .01em;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition: background-color .18s ease, border-color .18s ease, color .18s ease;
}

.btn-primary {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}
.btn-primary:hover { background: #26272a; border-color: #26272a; }

.btn-ghost {
  background: #fff;
  border-color: var(--line-2);
  color: var(--ink);
}
.btn-ghost:hover { border-color: var(--ink); }

.btn-sm { height: 38px; padding: 0 15px; font-size: 14px; border-radius: var(--radius-xs); }

.btn-block { width: 100%; }

.btn-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--line-2);
  padding-bottom: 2px;
  transition: border-color .18s ease;
}
.btn-link:hover { border-color: var(--ink); }
.btn-link .ic { width: 15px; height: 15px; }

/* ---------- 页头 ---------- */
.hdr {
  position: sticky;
  top: 0;
  z-index: 60;
  background: #fff;
  border-bottom: 1px solid var(--line);
}
.hdr.is-scrolled { box-shadow: 0 6px 18px -16px rgba(10, 10, 11, .6); }

.hdr-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex: none;
}
.brand img { height: 30px; width: auto; display: block; }
.brand-name {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--ink);
  text-transform: uppercase;
}

.nav {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-left: auto;
}
.nav a {
  position: relative;
  font-size: 14.5px;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  padding: 6px 0;
  transition: color .16s ease;
}
.nav a:hover { color: var(--ink); }
.nav a[aria-current="page"] { color: var(--ink); font-weight: 600; }
.nav a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
}

.hdr-cta { display: flex; align-items: center; gap: 10px; flex: none; margin-left: 4px; }

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  margin-left: auto;
  background: #fff;
  border: 1px solid var(--line-2);
  border-radius: var(--radius-xs);
  color: var(--ink);
  cursor: pointer;
}
.nav-toggle .ic { width: 18px; height: 18px; }
.nav-toggle .ic-close { display: none; }
.nav-toggle[aria-expanded="true"] .ic-menu { display: none; }
.nav-toggle[aria-expanded="true"] .ic-close { display: block; }

/* ---------- 首屏 ---------- */
.hero {
  padding: 68px 0 0;
  border-bottom: 1px solid var(--line);
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.02fr .98fr;
  gap: 60px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--muted);
}
.eyebrow::before {
  content: "";
  width: 7px;
  height: 7px;
  border: 1.5px solid var(--ink);
  border-radius: 50%;
  flex: none;
}

.hero h1 {
  margin-top: 18px;
  font-size: clamp(31px, 4.4vw, 50px);
  line-height: 1.16;
  letter-spacing: -.025em;
}
.hero-lede {
  margin-top: 20px;
  max-width: 34em;
  font-size: 16.5px;
  color: var(--muted);
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 30px;
}
.hero-note {
  margin-top: 16px;
  font-size: 13px;
  color: var(--muted-2);
}
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 24px;
}
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-size: 12.5px;
  color: var(--muted);
  white-space: nowrap;
}
.chip b { font-weight: 600; color: var(--ink); }

/* 实机截图：首屏与内容配图 */
.hero-figure { margin: 0; }
.shot-stage {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 28px 20px 26px;
  background: var(--surface);
  background-image:
    linear-gradient(to right, rgba(10, 10, 11, .04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(10, 10, 11, .04) 1px, transparent 1px);
  background-size: 26px 26px;
}
.shots {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 14px;
}
.shots img { display: block; height: auto; }
.shot-side {
  width: 184px;
  margin-bottom: 22px;
  filter: drop-shadow(0 14px 22px rgba(10, 10, 11, .3));
}
.shot-main {
  width: 272px;
  filter: drop-shadow(0 26px 40px rgba(10, 10, 11, .4));
}
.shot-cap {
  margin: 12px 0 0;
  text-align: center;
  font-size: 12px;
  color: var(--muted-2);
}
.cap-side { display: inline; }

/* 截图卡片 */
.shot-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.shot-card {
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
}
.shot-card h3 { font-size: 15px; margin: 0 0 6px; }
.shot-card p { font-size: 13px; color: var(--muted); margin: 0 0 20px; }
.shot-card img {
  display: block;
  width: 100%;
  max-width: 226px;
  height: auto;
  margin: 0 auto;
  filter: drop-shadow(0 14px 24px rgba(10, 10, 11, .2));
}
.shot-card .shot-more {
  margin: auto 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted-2);
}

/* 宽幅截图 */
.figure { margin: 0; }.figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: 0 36px 70px -46px rgba(10, 10, 11, .55);
}
.figure figcaption {
  margin-top: 14px;
  text-align: center;
  font-size: 13px;
  color: var(--muted);
}
.figure--narrow { max-width: 760px; margin-left: auto; margin-right: auto; }
.figure--shot { max-width: 620px; margin-left: auto; margin-right: auto; }
.figure--shot img { width: auto; max-width: 100%; margin-left: auto; margin-right: auto; }
.figure--panel { max-width: 420px; margin-left: auto; margin-right: auto; }
.figure--panel img {
  border: 0;
  box-shadow: none;
  filter: drop-shadow(0 24px 36px rgba(10, 10, 11, .3));
}

/* 事实条 */
.factbar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-top: 56px;
  border-top: 1px solid var(--line);
}
.factbar > div {
  padding: 20px 24px 26px 0;
  border-right: 1px solid var(--line);
}
.factbar > div:last-child { border-right: 0; }
.factbar dt {
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: 6px;
}
.factbar dd { margin: 0; font-size: 14px; color: var(--text); }

/* ---------- 区块 ---------- */
.section { padding: 84px 0; }
.section + .section { border-top: 1px solid var(--line); }
.section--surface { background: var(--surface); }
.section--tight { padding: 64px 0; }

.section-head { max-width: 760px; margin-bottom: 44px; }
.section-head.is-center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head h2 {
  margin-top: 14px;
  font-size: clamp(24px, 2.7vw, 34px);
  line-height: 1.28;
  letter-spacing: -.02em;
}
.section-head .lede {
  margin-top: 14px;
  font-size: 16.5px;
  color: var(--muted);
}
.section-head.is-center .lede { margin-left: auto; margin-right: auto; }

.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-6 { grid-template-columns: repeat(3, 1fr); gap: 16px; }

/* 卡片 */
.card {
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px;
  transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.card:hover {
  border-color: var(--line-2);
  box-shadow: var(--shadow-2);
  transform: translateY(-2px);
}
.card-icon {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  margin-bottom: 16px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  color: var(--ink);
}
.card-icon .ic { width: 19px; height: 19px; }
.card h3 { font-size: 16.5px; margin-bottom: 8px; }
.card p { font-size: 14.5px; color: var(--muted); line-height: 1.65; }
.card-note {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  color: var(--muted-2);
}
.card p + .card-note { margin-top: auto; }
.card-note a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--line-2);
  transition: border-color .16s ease;
}
.card-note a:hover { border-color: var(--ink); }

/* 编号论点 */
.points { border-top: 1px solid var(--line); }
.point {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 24px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}
.point-num {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--muted-2);
  padding-top: 3px;
}
.point h3 { font-size: 17px; margin-bottom: 8px; }
.point p { color: var(--muted); font-size: 15px; max-width: 62em; }

/* 功能磁贴 */
.tile {
  display: block;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fff;
  text-decoration: none;
  transition: border-color .18s ease, box-shadow .18s ease;
}
.tile:hover { border-color: var(--ink); box-shadow: var(--shadow-1); }
.tile-top { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; }
.tile-top .ic { width: 17px; height: 17px; color: var(--ink); }
.tile strong { font-size: 14.5px; font-weight: 600; color: var(--ink); }
.tile span { display: block; font-size: 12.5px; color: var(--muted); line-height: 1.55; }

/* 场景 */
.scene { display: flex; flex-direction: column; height: 100%; }
.scene .tag {
  align-self: flex-start;
  margin-bottom: 12px;
  padding: 2px 9px;
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 11.5px;
  letter-spacing: .04em;
  color: var(--muted);
}
.scene h3 { font-size: 16.5px; margin-bottom: 8px; }
.scene p { font-size: 14.5px; color: var(--muted); }

/* 可核对信息列表 */
.cred-list { border-top: 1px solid var(--line); }
.cred-item {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
}
.cred-item dt { color: var(--muted-2); font-size: 13px; }
.cred-item dd { margin: 0; color: var(--text); }
.cred-item a { text-decoration: none; border-bottom: 1px solid var(--line-2); }
.cred-item a:hover { border-color: var(--ink); }

/* 深色 CTA 带 */
.band {
  background: var(--ink);
  color: #fff;
  padding: 68px 0;
}
.band-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 40px;
  align-items: center;
}
.band .eyebrow { color: rgba(255, 255, 255, .6); }
.band .eyebrow::before { border-color: rgba(255, 255, 255, .7); }
.band h2 { color: #fff; margin-top: 14px; font-size: clamp(24px, 2.6vw, 32px); }
.band p { margin-top: 12px; color: rgba(255, 255, 255, .7); max-width: 46em; font-size: 15.5px; }
.band .btn-primary { background: #fff; border-color: #fff; color: var(--ink); }
.band .btn-primary:hover { background: #e9e9ea; border-color: #e9e9ea; }
.band .btn-ghost { background: transparent; border-color: rgba(255, 255, 255, .3); color: #fff; }
.band .btn-ghost:hover { border-color: #fff; }
.band-actions { display: flex; flex-wrap: wrap; gap: 12px; }

/* ---------- 子页页头 ---------- */
.page-hero { padding: 52px 0 44px; border-bottom: 1px solid var(--line); }
.page-hero h1 { margin-top: 14px; font-size: clamp(28px, 3.6vw, 42px); letter-spacing: -.022em; }
.title-row {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-top: 18px;
}
.title-row h1 { margin-top: 0; }
.app-icon {
  flex: none;
  display: block;
  width: 64px;
  height: 64px;
  filter: drop-shadow(0 8px 16px rgba(10, 10, 11, .18));
}
.page-hero .lede { margin-top: 16px; max-width: 46em; font-size: 16.5px; color: var(--muted); }

.crumbs { font-size: 12.5px; color: var(--muted-2); display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.crumbs a { text-decoration: none; color: var(--muted); }
.crumbs a:hover { color: var(--ink); }
.crumbs span[aria-hidden] { color: var(--line-2); }

.pills { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }

/* ---------- 通用内容 ---------- */
.prose { max-width: 760px; }
.prose h2 { margin: 46px 0 14px; font-size: 22px; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin: 30px 0 10px; font-size: 17px; }
.prose p { margin: 0 0 14px; color: var(--muted); font-size: 15.5px; }
.prose ul, .prose ol { margin: 0 0 16px; padding-left: 20px; color: var(--muted); font-size: 15.5px; }
.prose li { margin: 7px 0; }
.prose a { color: var(--ink); text-decoration: none; border-bottom: 1px solid var(--line-2); }
.prose a:hover { border-color: var(--ink); }
.prose strong { color: var(--ink); font-weight: 600; }

.callout {
  margin: 22px 0;
  padding: 18px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--ink);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 14.5px;
  color: var(--muted);
}
.callout strong { color: var(--ink); }

.kv { margin: 0; border-top: 1px solid var(--line); }
.kv > div {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 20px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
}
.kv dt { color: var(--muted-2); font-size: 13px; }
.kv dd { margin: 0; }

/* 表格 */
.table-wrap {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  overflow-x: auto;
}
table { width: 100%; border-collapse: collapse; font-size: 14.5px; min-width: 600px; }
th, td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--line); vertical-align: top; }
th {
  background: var(--surface);
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--muted);
  white-space: nowrap;
}
tr:last-child td { border-bottom: 0; }
td code {
  font-size: 12.5px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 2px 6px;
  white-space: nowrap;
}
p code,
li code,
dd code {
  font-size: .88em;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 1px 5px;
  color: var(--ink);
  white-space: nowrap;
}

/* 步骤 */
.steps { list-style: none; counter-reset: s; }
.steps li {
  position: relative;
  padding: 0 0 30px 58px;
  counter-increment: s;
}
.steps li::before {
  content: counter(s, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line-2);
  border-radius: 50%;
  background: #fff;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--muted);
}
.steps li::after {
  content: "";
  position: absolute;
  left: 18.5px;
  top: 42px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
}
.steps li:last-child { padding-bottom: 0; }
.steps li:last-child::after { display: none; }
.steps h3 { font-size: 16px; margin-bottom: 6px; }
.steps p { font-size: 14.5px; color: var(--muted); }

/* 下载卡 */
.dl-card {
  display: grid;
  grid-template-columns: 1.35fr .65fr;
  gap: 40px;
  padding: 36px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}
.dl-ver {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
}
.dl-ver strong { font-size: 26px; letter-spacing: -.02em; }
.dl-ver span { font-size: 13px; color: var(--muted); }
.dl-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.dl-side {
  border-left: 1px solid var(--line);
  padding-left: 40px;
  display: grid;
  gap: 14px;
  align-content: start;
}
.dl-side .kv-row { font-size: 13.5px; color: var(--muted); }
.dl-side .kv-row b { display: block; color: var(--ink); font-size: 14px; font-weight: 600; margin-top: 2px; }

.code-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xs);
  background: var(--surface);
  overflow-x: auto;
}
.code-row code { font-size: 13px; color: var(--ink); white-space: nowrap; }
.copy-btn {
  margin-left: auto;
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 30px;
  padding: 0 11px;
  border: 1px solid var(--line-2);
  border-radius: 6px;
  background: #fff;
  font-family: inherit;
  font-size: 12.5px;
  color: var(--muted);
  cursor: pointer;
  transition: border-color .16s ease, color .16s ease;
}
.copy-btn:hover { border-color: var(--ink); color: var(--ink); }
.copy-btn .ic { width: 13px; height: 13px; }

/* 校验行 */
.verified {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12.5px;
  color: var(--muted-2);
}
.verified .ic { width: 14px; height: 14px; }

/* 快速定位 */
.chipnav { display: flex; flex-wrap: wrap; gap: 8px; }
.chipnav a {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-size: 13px;
  color: var(--muted);
  text-decoration: none;
  transition: border-color .16s ease, color .16s ease;
}
.chipnav a:hover { border-color: var(--ink); color: var(--ink); }

/* 分组标题 */
.group { margin-top: 56px; }
.group:first-of-type { margin-top: 0; }
.group-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 14px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--line);
}
.group-head h2 { font-size: 19px; letter-spacing: -.01em; }
.group-head span { font-family: var(--mono); font-size: 12px; color: var(--muted-2); }

/* FAQ */
.faq { border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 19px 0;
  cursor: pointer;
  list-style: none;
  font-size: 15.5px;
  font-weight: 600;
  color: var(--ink);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  flex: none;
  width: 9px;
  height: 9px;
  margin-right: 4px;
  border-right: 1.5px solid var(--muted);
  border-bottom: 1.5px solid var(--muted);
  transform: rotate(45deg);
  transition: transform .2s ease;
}
.faq details[open] summary::after { transform: rotate(-135deg); }
.faq .ans { padding: 0 0 20px; max-width: 72ch; font-size: 14.8px; color: var(--muted); }
.faq .ans p + p { margin-top: 10px; }

/* ---------- 页脚 ---------- */
.ftr { border-top: 1px solid var(--line); background: var(--surface); }
.ftr-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 36px;
  padding: 56px 0 44px;
}
.ftr-brand img { height: 26px; width: auto; display: block; margin-bottom: 14px; }
.ftr-brand p { font-size: 13.5px; color: var(--muted); max-width: 26em; }
.ftr-col h2 {
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted-2);
  margin-bottom: 14px;
}
.ftr-col ul { list-style: none; display: grid; gap: 9px; }
.ftr-col a { font-size: 13.5px; color: var(--muted); text-decoration: none; }
.ftr-col a:hover { color: var(--ink); }
.ftr-bottom {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
  justify-content: space-between;
  padding: 20px 0 32px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  color: var(--muted-2);
}
.ftr-bottom p { max-width: 60em; }
.ftr-bottom a { color: var(--muted); text-decoration: none; }
.ftr-bottom a:hover { color: var(--ink); }

/* ---------- 下载弹窗 ---------- */
dialog.modal {
  width: min(760px, calc(100vw - 32px));
  max-width: none;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text);
}
dialog.modal:focus { outline: none; }
dialog.modal::backdrop { background: rgba(10, 10, 11, .55); }

.modal-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 28px;
  max-height: calc(100vh - 64px);
  overflow-y: auto;
  box-shadow: 0 40px 90px -40px rgba(0, 0, 0, .6);
}
.modal-head {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  justify-content: space-between;
}
.modal-head h2 { font-size: 21px; letter-spacing: -.015em; }
.modal-head p { margin-top: 7px; font-size: 13.5px; color: var(--muted); max-width: 44em; }
.modal-close {
  flex: none;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--line-2);
  border-radius: 50%;
  background: #fff;
  color: var(--muted);
  cursor: pointer;
  transition: color .16s ease, border-color .16s ease;
}
.modal-close:hover { color: var(--ink); border-color: var(--ink); }
.modal-close .ic { width: 15px; height: 15px; }

.qr-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 24px;
}
.qr {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  background: #fff;
  text-align: center;
}
.qr-frame {
  width: 100%;
  max-width: 208px;
  aspect-ratio: 1 / 1;
  margin: 0 auto;
  border: 1px solid var(--line-2);
  border-radius: 10px;
  background: #fff;
}
.qr-frame img { width: 100%; height: 100%; object-fit: contain; display: block; }
.qr-cap { margin-top: 14px; font-size: 13px; font-weight: 600; color: var(--ink); }
.qr-sub { margin-top: 4px; font-size: 12px; color: var(--muted-2); }

.modal-foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.modal-foot .verified { margin-left: auto; }

/* 无 JS 提示 */
.noscript {
  margin: 16px 0 0;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xs);
  background: var(--surface);
  font-size: 13.5px;
  color: var(--muted);
}

/* 进入动画（仅在 JS 可用时启用） */
.js .reveal { opacity: 0; transform: translateY(10px); transition: opacity .55s ease, transform .55s ease; }
.js .reveal.is-in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .hero-grid { gap: 40px; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .ftr-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .dl-card { grid-template-columns: 1fr; gap: 28px; }
  .dl-side { border-left: 0; border-top: 1px solid var(--line); padding-left: 0; padding-top: 24px; grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 900px) {
  .nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 68px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 24px 18px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 18px 30px -28px rgba(10, 10, 11, .7);
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 15px; }
  .nav a:last-child { border-bottom: 0; }
  .nav a[aria-current="page"]::after { display: none; }
  .nav-toggle { display: inline-flex; }
  .hdr-cta .btn { display: none; }
  .hdr-inner { gap: 16px; }

  .hero { padding-top: 48px; }
  .hero-grid { grid-template-columns: 1fr; }
  .factbar { grid-template-columns: repeat(2, 1fr); }
  .factbar > div:nth-child(2) { border-right: 0; }
  .factbar > div:nth-child(1),
  .factbar > div:nth-child(2) { border-bottom: 1px solid var(--line); }

  .grid-3, .grid-6 { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 64px 0; }
  .band-grid { grid-template-columns: 1fr; gap: 26px; }
  .ftr-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
  .point { grid-template-columns: 40px 1fr; gap: 16px; }
  .page-hero { padding: 40px 0 34px; }
  .shots { gap: 12px; }
  .shot-side { width: 158px; margin: 60px 0 0; }
  .shot-main { width: 238px; }
  .shot-grid { grid-template-columns: 1fr; max-width: 380px; margin: 0 auto; }
}

@media (max-width: 640px) {
  .wrap { padding: 0 20px; }
  body { font-size: 15.5px; }
  .hero-lede { font-size: 15.5px; }
  .grid-2, .grid-3, .grid-4, .grid-6 { grid-template-columns: 1fr; }
  .factbar { grid-template-columns: 1fr; }
  .factbar > div { border-right: 0; border-bottom: 1px solid var(--line); padding: 16px 0; }
  .factbar > div:last-child { border-bottom: 0; }
  .cred-item { grid-template-columns: 1fr; gap: 4px; }
  .kv > div { grid-template-columns: 1fr; gap: 4px; }
  .qr-grid { grid-template-columns: 1fr; }
  .modal-card { padding: 20px; }
  .dl-card { padding: 22px; }
  .dl-side { grid-template-columns: 1fr; }
  .ftr-grid { grid-template-columns: 1fr; }
  .hero-actions .btn { width: 100%; }
  .band-actions .btn { width: 100%; }
  .steps li { padding-left: 50px; }
  .section { padding: 52px 0; }
  .section-head { margin-bottom: 32px; }
  .shot-stage { padding: 22px 12px 10px; }
  .shots { gap: 8px; }
  .shot-side { width: 126px; margin: 48px 0 0; }
  .shot-main { width: 196px; }
}
@media (max-width: 420px) {
  .brand img { height: 26px; }
  .brand-name { font-size: 12px; letter-spacing: .16em; }
  .shots .shot-side { display: none; }
  .shot-main { width: 218px; }
  .cap-side { display: none; }
  .title-row { gap: 12px; }
  .app-icon { width: 52px; height: 52px; }
  .modal-foot .verified { margin-left: 0; }
  p code, li code, dd code { white-space: normal; word-break: break-word; }
}

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