/* 首页首屏：奶油画布、静态设置浮卡、一次性标题入场。 */
.hero { position: relative; background: var(--bg-panel); color: var(--text); overflow: hidden; height: clamp(700px, calc(100vh - var(--nav-h) - 52px), 820px); }
.hero-stage { position: relative; height: 100%; }
.hero-copy {
  position: relative; z-index: 2; height: 100%; max-width: 600px; margin-inline: auto; padding-inline: 20px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center;
}
.tag-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.tag, .badge {
  display: inline-flex; align-items: center; gap: 6px; min-height: 28px; padding: 4px 13px;
  max-width: 100%; overflow-wrap: anywhere; border-radius: var(--r-pill);
  background: var(--bg); color: var(--link); border: 1px solid var(--border);
  font-size: 12.5px; line-height: 1.5; letter-spacing: .01em;
}
.badge-first { background: var(--accent-soft); color: var(--accent-dark); border-color: var(--clear); }
.badge-recommended { background: var(--link-soft); color: var(--link); border-color: var(--clear); }
.badge-retired { background: var(--bg-panel-2); color: var(--text-muted); border-color: var(--border); }
.badge-step { background: var(--apricot); color: var(--apricot-ink); border-color: var(--clear); }
.dot { width: 6px; height: 6px; border-radius: var(--r-round); background: var(--accent); }
.hero-title { margin-top: 22px; font-size: clamp(34px, 3.4vw, 48px); line-height: 1.17; letter-spacing: -.005em; }
.line { display: block; overflow: hidden; padding-bottom: .1em; margin-bottom: -.1em; }
.line-in { display: inline-block; animation: rise .72s var(--ease-out) both; }
.line:nth-child(2) .line-in { animation-delay: .14s; }
.mark { position: relative; z-index: 0; display: inline-block; }
.mark::before {
  content: ""; position: absolute; z-index: -1; left: -.06em; right: -.06em; bottom: .1em; height: .3em;
  border-radius: var(--r-mark); background: var(--accent-soft); transform-origin: left center; animation: sweep .55s var(--ease-out) .6s both;
}
@keyframes rise { from { transform: translateY(104%); opacity: 0; } to { transform: none; opacity: 1; } }
@keyframes sweep { from { transform: scaleX(0); } to { transform: scaleX(1); } }
.cta-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; margin-top: 30px; }
.hero-lede { margin-top: 26px; max-width: 540px; font-size: 16.5px; line-height: 1.72; color: var(--text-muted); }
.hero-lede strong { color: var(--text); font-weight: var(--weight-semibold); }
.platforms { margin-top: 24px; display: flex; align-items: center; gap: 16px; }
.pf-label { font-size: 12.5px; color: var(--text-muted); letter-spacing: .04em; }
.pf-list { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; }
.pf-list li { margin: 0; }
.pf-list li + li { border-left: 1px solid var(--border-strong); }
.pf-link { display: inline-flex; align-items: center; gap: 7px; padding: 4px 14px; font-size: 14px; color: var(--text); transition: color var(--duration-fast) ease; }
.pf-link:hover { color: var(--accent); }
.pf-ico { width: 17px; height: 17px; fill: currentColor; flex-shrink: 0; }
.hero-visual { position: absolute; inset: 0; pointer-events: none; }
.float { position: absolute; z-index: 1; }
.float-a { left: 88px; top: 52px; }
.float-b { right: -126px; top: 40px; }
.float-c { left: -140px; bottom: 60px; }
.float-d { right: 76px; bottom: 70px; }
.card { position: relative; z-index: 1; background: var(--bg); color: var(--text); border-radius: var(--r-card); overflow: hidden; font-size: 13px; text-align: left; }
.card-a { width: 296px; transform: rotate(-2deg); box-shadow: var(--shadow-near); }
.card-b { width: 380px; transform: rotate(1.5deg); box-shadow: var(--shadow-far); }
.card-c { width: 430px; transform: rotate(1deg); box-shadow: var(--shadow-far); display: grid; grid-template-columns: 140px minmax(0, 1fr); }
.card-d { width: 330px; transform: rotate(-1.5deg); box-shadow: var(--shadow-near); }
.card-bar { display: flex; align-items: center; justify-content: space-between; height: 44px; padding-inline: 16px; background: var(--bg-panel-2); color: var(--text); border-bottom: 1px solid var(--border); }
.card-title { font-size: 13.5px; font-weight: var(--weight-semibold); letter-spacing: .01em; }
.card-note { font-size: 11.5px; color: var(--text-muted); }
.win-ctrl { display: inline-flex; gap: 12px; color: var(--text-muted); }
.win-ctrl svg { width: 10px; height: 10px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; }
.opt-list { list-style: none; padding: 8px; margin: 0; }
.opt { display: flex; align-items: center; gap: 10px; min-height: 36px; padding: 6px 10px; margin: 0; border-radius: var(--r-item); font-size: 13.5px; color: var(--text-muted); }
.radio { width: 16px; height: 16px; flex-shrink: 0; border-radius: var(--r-round); border: 1.5px solid var(--border-strong); display: grid; place-items: center; }
.opt.is-on { background: var(--accent-soft); color: var(--accent-dark); font-weight: var(--weight-medium); }
.opt.is-on .radio { border-color: var(--accent); }
.opt.is-on .radio::after { content: ""; width: 8px; height: 8px; border-radius: var(--r-round); background: var(--accent); }
.card-body { padding: 16px 20px 20px; }
.f-label { display: block; font-size: 12px; color: var(--text-muted); margin-bottom: 6px; }
.field { display: flex; align-items: center; min-height: 36px; padding: 6px 12px; border: 1px solid var(--border-strong); border-radius: var(--r-field); background: var(--bg); color: var(--text); font-family: var(--font-mono); font-size: 12.5px; overflow-wrap: anywhere; }
.mini-btn { display: inline-flex; align-items: center; min-height: 30px; margin-top: 14px; padding: 5px 14px; border-radius: var(--r-pill); background: var(--accent); color: var(--on-accent); font-size: 12.5px; font-weight: var(--weight-medium); }
.rail { background: var(--bg-panel-2); color: var(--text); border-right: 1px solid var(--border); padding: 14px 10px; }
.rail ul { list-style: none; margin: 0; padding: 0; }
.rail li { padding: 7px 10px; margin: 0; border-radius: var(--r-field); font-size: 12px; color: var(--text-muted); white-space: nowrap; }
.rail li.is-on { background: var(--bg); color: var(--text); font-weight: var(--weight-medium); }
.pane { min-width: 0; padding: 16px 20px 18px; }
.pane-kicker { font-size: 11.5px; color: var(--text-muted); letter-spacing: .04em; }
.pane-title { font-size: 14px; font-weight: var(--weight-semibold); margin-top: 2px; }
.set-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding-top: 12px; padding-bottom: 12px; border-top: 1px solid var(--border); font-size: 13px; }
.pane-title + .set-row { margin-top: 12px; }
.set-row .field { width: 92px; min-height: 32px; justify-content: center; }
.switch { position: relative; flex-shrink: 0; width: 38px; height: 22px; border-radius: var(--r-pill); background: var(--accent); color: var(--on-accent); }
.switch::after { content: ""; position: absolute; top: 2px; right: 2px; width: 18px; height: 18px; border-radius: var(--r-round); background: var(--bg); box-shadow: var(--shadow-knob); }
.rule-head, .rule { display: grid; grid-template-columns: minmax(0, 1fr) 16px 62px; align-items: center; gap: 8px; }
.rule-head { font-size: 11.5px; color: var(--text-muted); letter-spacing: .04em; padding-bottom: 8px; }
.rule { padding-top: 11px; padding-bottom: 11px; border-top: 1px solid var(--border); }
.rule code { font-family: var(--font-mono); font-size: 12.5px; color: var(--text); }
.rule-arrow { font-family: var(--font-mono); font-size: 12.5px; color: var(--text-muted); text-align: center; }
.out { justify-self: start; display: inline-flex; align-items: center; min-height: 22px; padding: 2px 9px; border-radius: var(--r-pill); font-family: var(--font-mono); font-size: 11.5px; }
.out-proxy { background: var(--accent-soft); color: var(--accent-dark); }
.out-direct { background: var(--link-soft); color: var(--link); }
.card-d .card-body { padding: 14px 20px 12px; }
.chip { position: absolute; z-index: 2; display: inline-flex; align-items: center; gap: 8px; min-height: 36px; padding: 6px 16px 6px 13px; border-radius: var(--r-pill); background: var(--apricot); color: var(--apricot-ink); font-size: 14px; font-weight: var(--weight-medium); white-space: nowrap; }
.chip .ico { width: 17px; height: 17px; }
.tether { position: absolute; z-index: 0; overflow: visible; }
.tether path { fill: none; stroke: var(--apricot-line); stroke-width: 1.5; stroke-linecap: round; }
.float-a .chip { left: 128px; top: 262px; }
.float-a .tether { left: 50px; top: 160px; width: 80px; height: 122px; }
.float-b .chip { right: calc(100% + 60px); top: 192px; }
.float-b .tether { left: -60px; top: 150px; width: 120px; height: 62px; }
.float-c .chip { left: 420px; top: -88px; }
.float-c .tether { left: 340px; top: -70px; width: 80px; height: 86px; }
.float-d .chip { left: 40px; top: -78px; }
.float-d .tether { left: 150px; top: -60px; width: 110px; height: 82px; }
.dl-peek { background: var(--bg); color: var(--text); padding-top: 34px; padding-bottom: 96px; }
.dl-grid { margin-top: 36px; display: grid; grid-template-columns: minmax(0, 3fr) minmax(0, 1fr); gap: 20px; }
.dl-desk { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; padding: 8px; background: var(--bg-panel-2); color: var(--text); border-radius: var(--r-panel); }
.dl-item, .dl-android { min-width: 0; display: flex; flex-direction: column; gap: 10px; padding: 26px 24px; border-radius: var(--r-card); background: var(--bg); color: var(--text); transition: box-shadow .2s ease; }
.dl-item:hover, .dl-android:hover { box-shadow: var(--shadow-far); }
.dl-android { background: var(--bg-panel); color: var(--text); border-radius: var(--r-panel); }
.dl-name { font-family: var(--font-display); font-weight: var(--weight-regular); font-size: 22px; line-height: 1.25; }
.dl-desc { font-size: 14.5px; line-height: 1.65; color: var(--text-muted); }
.dl-go { margin-top: auto; font-size: 14.5px; color: var(--link); }
/* 目录式功能切换，也可用于下载页平台选择。 */
.tabs { min-width: 0; }
.tab-list, [role="tablist"] { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.tab-list [role="tab"], .feature-tabs [role="tab"] {
  min-height: 44px; padding: 10px 20px; border-radius: var(--r-pill);
  background: var(--bg-panel-2); color: var(--text-muted); text-align: left;
}
.tab-list [role="tab"][aria-selected="true"] { background: var(--accent); color: var(--on-accent); }
.tab-panel { min-width: 0; margin-top: 24px; }
.feature-tabs { display: grid; grid-template-columns: minmax(180px, .8fr) minmax(0, 2fr); gap: 56px; }
.feature-tabs > [role="tablist"] { display: flex; flex-direction: column; align-items: stretch; justify-content: center; gap: 14px; }
.feature-tabs [role="tab"] { position: relative; padding: 16px 24px; border-radius: var(--r-field); background: var(--clear); color: var(--text-muted); font-family: var(--font-display); font-size: 25px; font-weight: var(--weight-regular); }
.feature-tabs [role="tab"][aria-selected="true"] { background: var(--accent); color: var(--on-accent); }
.feature-tabs [role="tab"][aria-selected="true"]::before { content: ""; position: absolute; inset: 12px auto 12px 0; width: 3px; border-radius: var(--r-mark); background: var(--accent); }
.feature-panel { position: relative; min-width: 0; padding: 48px; border-radius: var(--r-panel); background: var(--bg-panel); color: var(--text); }
.feature-panel p { margin-top: 32px; line-height: 1.85; color: var(--text-muted); }
.feature-panel .btn { margin-top: 24px; }
.feature-mock { position: relative; max-width: 430px; margin-inline: auto; }
.feature-mock .card { box-shadow: var(--shadow-near); }
.feature-label { position: absolute; top: -14px; right: -12px; z-index: 3; }
.toc { position: sticky; top: 16px; z-index: 10; display: flex; gap: 8px; overflow-x: auto; max-width: 100%; padding: 12px; border-radius: var(--r-panel); background: var(--bg-panel-2); color: var(--text); overscroll-behavior-inline: contain; }
.toc a { display: inline-flex; align-items: center; flex-shrink: 0; min-height: 44px; padding: 8px 16px; border-radius: var(--r-pill); font-size: 14px; }
.toc a:hover, .toc a[aria-current="location"] { background: var(--bg); color: var(--accent-dark); }
.faq-item { border-bottom: 1px solid var(--border); }
.faq-item summary { position: relative; min-height: 64px; padding: 20px 36px 20px 0; list-style: none; cursor: pointer; font-weight: var(--weight-medium); }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; position: absolute; right: 8px; top: 20px; color: var(--accent); }
.faq-item[open] summary::after { content: "−"; }
.faq-answer { padding-bottom: 24px; color: var(--text-muted); line-height: 1.8; }
.term-card { min-width: 0; padding: 28px; background: var(--bg-panel-2); color: var(--text); border-radius: var(--r-card); }
.term-card h3 { margin-top: 16px; }
.term-card p { margin-top: 16px; color: var(--text-muted); }
.term-category { font-family: var(--font-mono); font-size: 12px; color: var(--accent-dark); }
.client-card { min-width: 0; padding: 32px; border-radius: var(--r-panel); background: var(--bg); color: var(--text); box-shadow: var(--shadow-far); }
.client-head { display: flex; align-items: center; flex-wrap: wrap; gap: 16px; }
.client-head > div { min-width: 0; }
.app-logo { width: 56px; height: 56px; flex-shrink: 0; }
.client-card p { margin-top: 20px; color: var(--text-muted); }
.client-meta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 16px; color: var(--text-muted); font-size: 13px; }
.client-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.article-card { min-width: 0; display: flex; flex-direction: column; gap: 18px; padding: 28px; border-radius: var(--r-card); background: var(--bg); color: var(--text); box-shadow: var(--shadow-far); }
.article-meta { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; color: var(--text-muted); font-size: 12.5px; }
.article-card h3 { font-size: 23px; line-height: 1.5; }
.article-card h3 a:hover { color: var(--accent); }
.article-card p { color: var(--text-muted); font-size: 14.5px; line-height: 1.8; }
.article-card > .text-link { margin-top: auto; }
.callout { margin-inline: 0; padding: 24px 28px; border-left: 3px solid var(--accent); border-radius: var(--r-field) var(--r-card) var(--r-card) var(--r-field); background: var(--bg-panel-2); color: var(--text); }
.callout strong { display: block; margin-bottom: 8px; }
.callout p { color: var(--text-muted); }
.callout-warning { border-left-color: var(--warn); }
.callout-error { border-left-color: var(--error); }
.table-scroll { max-width: 100%; min-width: 0; overflow-x: auto; -webkit-overflow-scrolling: touch; border-radius: var(--r-card); }
.data-table { width: 100%; border-collapse: collapse; text-align: left; font-size: 14px; }
.data-table th, .data-table td, .prose table th, .prose table td {
  min-width: 7em; padding: 16px 20px; border-bottom: 1px solid var(--border);
  overflow-wrap: normal; word-break: normal; vertical-align: top;
}
.data-table th, .prose table th { background: var(--bg-panel-2); color: var(--text); font-weight: var(--weight-medium); }
.data-table td, .prose table td { background: var(--bg); color: var(--text-muted); }
.prose table { display: block; overflow-x: auto; -webkit-overflow-scrolling: touch; max-width: 100%; min-width: 0; border-collapse: collapse; }
.prose table code, .data-table code { overflow-wrap: anywhere; }
.download-guide { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-top: 48px; padding: 28px 32px; border-radius: var(--r-panel); background: var(--bg-panel-2); color: var(--text); }
.download-guide p { margin-top: 10px; color: var(--text-muted); }
.download-guide > * { min-width: 0; }
.dl-fab {
  position: fixed; right: max(20px, env(safe-area-inset-right)); bottom: max(20px, env(safe-area-inset-bottom)); z-index: 25;
  display: inline-flex; align-items: center; gap: 12px; max-width: calc(100vw - 40px);
  padding: 14px 22px; border-radius: var(--r-pill); background: var(--accent); color: var(--on-accent); box-shadow: var(--shadow-near);
}
.dl-fab:hover { background: var(--accent-dark); color: var(--on-accent); }
.dl-fab .ico { width: 22px; height: 22px; }
.dl-fab strong { display: block; font-size: 14px; font-weight: var(--weight-medium); }
.dl-fab small { display: block; font-size: 12px; }
.preview-section { padding-top: 64px; padding-bottom: 64px; }
.preview-section h2 { margin-bottom: 32px; }
.preview-section h3 + p { margin-top: 12px; }
.swatch-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.swatch { min-width: 0; padding: 16px; border: 1px solid var(--border); border-radius: var(--r-card); }
.swatch::before { content: ""; display: block; height: 64px; margin-bottom: 12px; border-radius: var(--r-field); background: var(--swatch); }
.swatch code { font-size: 12px; }
.swatch-bg { --swatch: var(--bg); }
.swatch-panel { --swatch: var(--bg-panel); }
.swatch-panel2 { --swatch: var(--bg-panel-2); }
.swatch-border { --swatch: var(--border); }
.swatch-border-strong { --swatch: var(--border-strong); }
.swatch-accent { --swatch: var(--accent); }
.swatch-accent-dark { --swatch: var(--accent-dark); }
.swatch-accent-soft { --swatch: var(--accent-soft); }
.swatch-link { --swatch: var(--link); }
.swatch-link-soft { --swatch: var(--link-soft); }
.swatch-apricot { --swatch: var(--apricot); }
.swatch-apricot-ink { --swatch: var(--apricot-ink); }
.swatch-apricot-line { --swatch: var(--apricot-line); }
.swatch-text { --swatch: var(--text); }
.swatch-muted { --swatch: var(--text-muted); }
.swatch-faint { --swatch: var(--text-faint); }
.swatch-on { --swatch: var(--on-accent); }
.swatch-success { --swatch: var(--success); }
.swatch-warn { --swatch: var(--warn); }
.swatch-error { --swatch: var(--error); }
.swatch-clear { --swatch: var(--clear); }
.swatch-veil { --swatch: var(--veil); }
.type-display { font-family: var(--font-display); font-size: 48px; line-height: 1.2; }
.type-subtitle { font-size: 20px; line-height: 1.7; }
.preview-focus { outline: 2px solid var(--accent); outline-offset: 3px; }
.preview-fab { position: static; margin-top: 24px; }
@media (max-width: 1240px) {
  .float-a { transform: scale(.86); transform-origin: top left; }
  .float-b { transform: scale(.86); transform-origin: top right; }
  .float-c { transform: scale(.86); transform-origin: bottom left; }
  .float-d { transform: scale(.86); transform-origin: bottom right; }
}
@media (min-width: 861px) and (max-width: 1000px) {
  .hero-copy { max-width: 520px; }
  .float-a { left: 20px; }
  .float-d { right: 20px; }
}
@media (max-width: 860px) {
  .hero { height: auto; }
  .hero-stage { display: flex; flex-direction: column; gap: 12px; padding: 40px 18px 36px; }
  .hero-copy { height: auto; padding-top: 0; padding-bottom: 0; max-width: none; }
  .hero-title { font-size: clamp(26px, 7vw, 30px); }
  .hero-lede { font-size: 15px; }
  .platforms { flex-direction: column; gap: 8px; }
  .pf-list { flex-wrap: wrap; justify-content: center; row-gap: 8px; }
  .pf-link { padding: 4px 10px; font-size: 13px; }
  .hero-visual { position: relative; inset: auto; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin-top: 18px; }
  .float, .float-a, .float-b, .float-c, .float-d { position: static; transform: none; min-width: 0; }
  .float-b, .float-c, .hero-visual .chip, .hero-visual .tether { display: none; }
  .card-a, .card-d { width: 100%; font-size: 11.5px; }
  .card-a { transform: rotate(-1deg); }
  .card-d { transform: rotate(1deg); }
  .card-bar { height: 36px; padding-inline: 10px; }
  .card-title { font-size: 12px; }
  .card-note, .win-ctrl { display: none; }
  .opt { min-height: 30px; padding: 6px; gap: 6px; font-size: 11px; }
  .radio { width: 13px; height: 13px; }
  .opt.is-on .radio::after { width: 6px; height: 6px; }
  .card-d .card-body { padding: 10px 10px 6px; }
  .rule-head { display: none; }
  .rule { grid-template-columns: minmax(0, 1fr); gap: 4px; }
  .rule-arrow { display: none; }
  .rule code, .out { font-size: 10.5px; }
  .dl-peek { padding-top: 40px; padding-bottom: 64px; }
  .dl-grid, .dl-desk { grid-template-columns: minmax(0, 1fr); }
  .feature-tabs { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .feature-tabs > [role="tablist"] { flex-direction: row; flex-wrap: nowrap; justify-content: flex-start; overflow-x: auto; }
  .feature-tabs [role="tab"] { flex-shrink: 0; font-family: var(--font-body); font-size: 14px; padding: 10px 20px; border-radius: var(--r-pill); background: var(--bg-panel-2); color: var(--text-muted); }
  .feature-tabs [role="tab"][aria-selected="true"] { background: var(--accent); color: var(--on-accent); }
  .feature-tabs [role="tab"][aria-selected="true"]::before { display: none; }
  .feature-panel { padding: 32px 24px; }
  .swatch-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .download-guide { flex-direction: column; align-items: flex-start; }
}
@media (max-width: 640px) {
  .client-card, .article-card, .term-card { padding: 24px; }
  .type-display { font-size: 30px; }
  .download-guide { padding: 24px; }
  .dl-fab { padding: 12px 18px; }
}
@media (prefers-reduced-motion: reduce) {
  .line-in, .mark::before { animation: none; }
}