/* 官网. A plain document in the product's AI Studio look: left-aligned, a narrow label column and a
   content column (Swiss grid), hairlines between sections, real screenshots with captions. No
   centred hero, card grids, alternating bands, gradients or decorative colour.
   Light and dark follow the visitor's system. */
:root {
  color-scheme: light;
  --font: "PingFang SC", "SourceHanSansSC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --mono: "SF Mono", ui-monospace, Menlo, Consolas, monospace;
  --bg: #FFFFFF; --surface-2: #F2F3F5;
  --text: #1F2329; --text-2: #4A5058; --muted: #646A73;
  --border: #DADFE7; --border-soft: #EBEEF2;
  --primary: #1F2329; --on-primary: #FFFFFF;
  --warning-text: #8A5A10; --warning-bg: #FBF5E9;
  --link: #34599F; --focus: #34599F;
  --r-sm: 6px; --r-md: 8px;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #121212; --surface-2: #232323;
    --text: #ECECEC; --text-2: #C9C9C9; --muted: #A3A3A3;
    --border: #3A3A3A; --border-soft: #2A2A2A;
    --primary: #E6E6E6; --on-primary: #121212;
    --warning-text: #E3BF77; --warning-bg: rgba(217, 174, 91, .13);
    --link: #A5BFEB; --focus: #A5BFEB;
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 72px; -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 400 16px/1.8 var(--font); -webkit-font-smoothing: antialiased; }
a { color: var(--link); text-decoration: none; } a:hover { text-decoration: underline; text-underline-offset: 3px; }
code { font-family: var(--mono); font-size: 14px; padding: 1px 5px; border-radius: 4px; background: var(--surface-2); overflow-wrap: anywhere; }
h1, h2, h3 { text-wrap: balance; }
p { margin: 0; text-wrap: pretty; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; border-radius: 4px; }
.wrap { width: min(1080px, 100% - 40px); margin: 0 auto; }
.skip { position: absolute; left: 12px; top: -48px; z-index: 30; padding: 8px 14px; border-radius: var(--r-sm); background: var(--primary); color: var(--on-primary); }
.skip:focus { top: 12px; text-decoration: none; }

/* header */
.top { position: sticky; top: 0; z-index: 10; background: var(--bg); border-bottom: 1px solid var(--border-soft); }
.top-inner { display: flex; align-items: center; gap: 28px; height: 56px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--text); font-weight: 600; font-size: 15px; white-space: nowrap; }
.brand:hover { text-decoration: none; }
.brand img { border-radius: 5px; }
.top-nav { display: flex; gap: 24px; margin-left: auto; font-size: 14px; }
.top-nav a { color: var(--text-2); padding: 8px 0; } .top-nav a:hover { color: var(--text); text-decoration: none; }
@media (max-width: 720px) { .top-nav { display: none; } .top-download { margin-left: auto; } }

/* buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 40px; padding: 0 18px; border: 1px solid var(--border); border-radius: var(--r-sm); background: var(--bg); color: var(--text); font: inherit; font-size: 15px; font-weight: 500; cursor: pointer; white-space: nowrap; transition: background-color .15s ease-out; touch-action: manipulation; }
.btn:hover { text-decoration: none; background: var(--surface-2); }
.btn-primary { border-color: var(--primary); background: var(--primary); color: var(--on-primary); }
.btn-primary:hover { background: color-mix(in srgb, var(--primary) 86%, var(--bg)); }
.btn-sm { min-height: 32px; padding: 0 12px; font-size: 14px; }
.btn[aria-disabled="true"], a[aria-disabled="true"] { opacity: .45; pointer-events: none; }
@media (pointer: coarse) { .btn { min-height: 44px; } }
.text-link { font-size: 15px; padding: 8px 0; }

/* opening: left-aligned, then the product */
.hero { padding: 72px 0 24px; }
.hero h1 { margin: 0; font-size: 36px; line-height: 1.3; font-weight: 600; }
.lead { margin-top: 16px; max-width: 640px; font-size: 18px; line-height: 1.75; color: var(--text-2); }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 20px; margin-top: 28px; }
.meta { font-size: 14px; color: var(--muted); font-variant-numeric: tabular-nums; }
.hero .meta { margin-top: 12px; }
.browser-note { margin-top: 16px; padding: 10px 14px; border-radius: var(--r-md); background: var(--warning-bg); color: var(--warning-text); font-size: 15px; max-width: 620px; }
@media (max-width: 720px) { .hero { padding-top: 48px; } .hero h1 { font-size: 28px; } .lead { font-size: 16px; } }

/* screenshots: the real product with a plain border and a caption */
.shot { margin: 0; }
.shot img { display: block; width: 100%; height: auto; border: 1px solid var(--border); border-radius: var(--r-md); background: var(--surface-2); }
.shot figcaption { margin-top: 10px; font-size: 13px; color: var(--muted); }
.shot-hero { margin-top: 48px; }
.shot-panel { max-width: 340px; }

/* sections: a label column and a content column */
.section { display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: 48px; padding: 72px 0; border-top: 1px solid var(--border-soft); }
.section > h2 { margin: 0; font-size: 18px; line-height: 1.6; font-weight: 600; align-self: start; position: sticky; top: 84px; }
.section-body { min-width: 0; max-width: 760px; }
@media (max-width: 820px) { .section { grid-template-columns: 1fr; gap: 20px; padding: 56px 0; } .section > h2 { position: static; font-size: 22px; } }

.feature + .feature { margin-top: 56px; }
.feature h3 { margin: 0; font-size: 18px; line-height: 1.6; font-weight: 600; }
.feature > p { margin-top: 8px; color: var(--text-2); }
.feature .shot { margin-top: 24px; }

.facts { margin: 56px 0 0; border-top: 1px solid var(--border-soft); }
.facts > div { display: grid; grid-template-columns: 140px minmax(0, 1fr); gap: 24px; padding: 16px 0; border-bottom: 1px solid var(--border-soft); }
.facts dt { font-weight: 600; }
.facts dd { margin: 0; color: var(--text-2); }
@media (max-width: 560px) { .facts > div { grid-template-columns: 1fr; gap: 4px; } }

.intro { color: var(--text-2); }
.steps { margin: 24px 0 0; padding: 0; list-style: none; counter-reset: step; border-top: 1px solid var(--border-soft); }
.steps li { counter-increment: step; display: grid; grid-template-columns: 32px minmax(0, 1fr); column-gap: 8px; padding: 18px 0; border-bottom: 1px solid var(--border-soft); }
.steps li::before { content: counter(step) "."; grid-row: 1 / 3; font-weight: 600; font-variant-numeric: tabular-nums; line-height: 1.6; font-size: 17px; }
.steps h3 { margin: 0; font-size: 17px; line-height: 1.6; font-weight: 600; }
.steps p { margin-top: 4px; color: var(--text-2); }
.copy { margin: 0 2px; padding: 0 6px; border: 1px solid var(--border); border-radius: 4px; background: var(--bg); color: var(--text-2); font: inherit; font-size: 13px; line-height: 22px; cursor: pointer; vertical-align: 1px; }
.copy:hover { background: var(--surface-2); color: var(--text); }
.sub { margin: 40px 0 8px; font-size: 17px; font-weight: 600; }
.sub + p { color: var(--text-2); }

.faq { border-top: 1px solid var(--border-soft); }
details { border-bottom: 1px solid var(--border-soft); }
summary { display: flex; justify-content: space-between; align-items: center; gap: 16px; min-height: 52px; padding: 12px 0; cursor: pointer; font-weight: 500; list-style: none; }
summary::-webkit-details-marker { display: none; }
summary::after { content: '+'; flex: none; width: 16px; text-align: center; color: var(--muted); font-weight: 400; font-size: 18px; }
details[open] summary::after { content: '−'; }
details p { margin-bottom: 16px; color: var(--text-2); }

.changelog { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--border-soft); }
.changelog > li { display: grid; grid-template-columns: 140px minmax(0, 1fr); gap: 24px; padding: 16px 0; border-bottom: 1px solid var(--border-soft); }
.changelog .ver { font-weight: 600; font-variant-numeric: tabular-nums; }
.changelog .ver small { display: block; font-weight: 400; color: var(--muted); font-size: 14px; }
.changelog .tag { margin-left: 8px; font-size: 13px; font-weight: 400; color: var(--muted); }
.changelog ul { margin: 0; padding-left: 18px; color: var(--text-2); }
.changelog .empty { display: block; color: var(--muted); }
@media (max-width: 560px) { .changelog > li { grid-template-columns: 1fr; gap: 4px; } }

.foot { padding: 32px 0 48px; border-top: 1px solid var(--border-soft); font-size: 14px; color: var(--muted); }
.foot-inner { display: grid; gap: 6px; }
.foot-download { display: flex; flex-wrap: wrap; gap: 12px; align-items: baseline; }
.foot-download a { font-weight: 500; }

#toast { position: fixed; left: 50%; bottom: 28px; z-index: 20; transform: translateX(-50%); padding: 10px 16px; border-radius: var(--r-md); background: var(--primary); color: var(--on-primary); font-size: 15px; opacity: 0; pointer-events: none; transition: opacity .2s ease-out; }
#toast.show { opacity: 1; }
.nowrap { white-space: nowrap; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition: none !important; } }
@media (pointer: coarse) { .copy { padding: 0 10px; line-height: 32px; } }