:root {
  /* 与桌面端 globals.css 同一套品牌令牌：清爽协作感（微信 / 飞书取向）。 */
  --kk-bg: #f5f6f7;
  --kk-surface: #ffffff;
  --kk-border: #e5e6eb;
  --kk-text: #1f2329;
  --kk-muted: #646a73;
  --kk-muted-strong: #4e5969;
  --kk-muted-weak: #8f959e;
  --kk-accent: #3370ff;
  --kk-accent-hover: #245bdb;
  --kk-success: #07c160;
  --kk-radius-sm: 8px;
  --kk-radius-md: 10px;
  --kk-radius-lg: 12px;
  --kk-radius-xl: 20px;
  --kk-surface-subtle: #f2f3f5;
  --kk-shadow-sm: 0 1px 3px rgba(31, 35, 41, .06);
  --kk-shadow-md: 0 4px 12px rgba(31, 35, 41, .08);
  --kk-shadow-lg: 0 16px 48px rgba(31, 35, 41, .12);

  color: var(--kk-text);
  background: var(--kk-bg);
  font-family: "MiSans", "Microsoft YaHei UI", "PingFang SC", Inter, ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  line-height: 1.5;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}

* { box-sizing: border-box; }
body { margin: 0; min-width: 320px; background: var(--kk-bg); }
a { color: inherit; }
.shell { width: min(1120px, calc(100% - 48px)); margin: 0 auto; }

.nav { min-height: 72px; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 600; }
.brand-mark { display: grid; place-items: center; width: 32px; height: 32px; border-radius: var(--kk-radius-sm); color: #fff; background: var(--kk-accent); font-size: 15px; font-weight: 600; }
.nav-note, .meta, .version, .footer { color: var(--kk-muted); font-size: 13px; }

.hero { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr); align-items: center; gap: clamp(32px, 5vw, 72px); padding: clamp(48px, 7vw, 88px) 0 88px; }
.hero-copy { max-width: 560px; }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; margin: 0 0 20px; padding: 6px 12px; border-radius: 999px; background: rgba(51, 112, 255, .08); color: var(--kk-accent); font-size: 12px; font-weight: 600; letter-spacing: .02em; }
h1 { font-size: clamp(36px, 4.4vw, 54px); line-height: 1.18; letter-spacing: -.02em; margin: 0; font-weight: 600; }
.lead { color: var(--kk-muted-strong); font-size: clamp(16px, 1.4vw, 18px); margin: 20px 0 32px; }
.actions { display: flex; align-items: center; flex-wrap: wrap; gap: 20px; }
.download { display: inline-flex; align-items: center; gap: 10px; min-height: 48px; padding: 0 26px; border-radius: 999px; color: #fff; background: var(--kk-accent); text-decoration: none; font-weight: 600; box-shadow: 0 6px 20px rgba(51, 112, 255, .22); transition: background .18s ease-out, box-shadow .18s ease-out; }
.download:hover { background: var(--kk-accent-hover); box-shadow: 0 10px 28px rgba(51, 112, 255, .28); }
.version strong { color: var(--kk-text); font-weight: 600; }
.meta { margin-top: 18px; }

/* 首屏产品预览：静态模拟窗口，让下载页一眼看到软件长什么样。 */
.preview { perspective: 1400px; }
.preview-window { border-radius: var(--kk-radius-xl); background: var(--kk-surface); box-shadow: var(--kk-shadow-lg); overflow: hidden; }
.preview-bar { display: flex; align-items: center; gap: 7px; padding: 14px 18px; background: var(--kk-surface-subtle); }
.preview-bar i { width: 10px; height: 10px; border-radius: 999px; background: #d7d9de; }
.preview-body { display: grid; grid-template-columns: 96px minmax(0, 1fr); min-height: 340px; }
.preview-side { display: flex; flex-direction: column; gap: 10px; padding: 16px 12px; background: #eef0f3; }
.preview-brand { display: grid; place-items: center; width: 28px; height: 28px; margin-bottom: 6px; border-radius: var(--kk-radius-sm); background: var(--kk-accent); color: #fff; font-size: 12px; font-weight: 600; }
.preview-row { height: 30px; border-radius: var(--kk-radius-md); background: rgba(255, 255, 255, .55); }
.preview-row.active { background: var(--kk-surface); box-shadow: var(--kk-shadow-sm); }
.preview-chat { display: flex; flex-direction: column; gap: 12px; padding: 20px; }
.bubble { max-width: 84%; padding: 12px 16px; border-radius: var(--kk-radius-lg); font-size: 13px; line-height: 1.6; }
.bubble.user { align-self: flex-end; background: var(--kk-accent); color: #fff; border-bottom-right-radius: 4px; }
.bubble.bot { align-self: flex-start; background: var(--kk-surface-subtle); color: var(--kk-muted-strong); border-bottom-left-radius: 4px; }
.preview-step { display: inline-flex; align-items: center; gap: 7px; margin-top: 10px; padding: 5px 12px; border-radius: 999px; background: var(--kk-surface); color: var(--kk-accent); font-size: 12px; box-shadow: var(--kk-shadow-sm); }
.preview-step::before { content: ""; width: 6px; height: 6px; border-radius: 999px; background: var(--kk-success); }
.preview-input { display: flex; align-items: center; justify-content: space-between; margin-top: auto; padding: 13px 14px 13px 18px; border-radius: 999px; background: var(--kk-surface-subtle); color: var(--kk-muted-weak); font-size: 13px; }
.preview-send { width: 26px; height: 26px; border-radius: 999px; background: var(--kk-accent); }

.proof { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; padding: 0 0 88px; }
.proof article { padding: 28px 24px; border-radius: var(--kk-radius-lg); background: var(--kk-surface); box-shadow: var(--kk-shadow-sm); transition: box-shadow .18s ease-out; }
.proof article:hover { box-shadow: var(--kk-shadow-md); }
.number { display: grid; place-items: center; width: 32px; height: 32px; border-radius: var(--kk-radius-sm); background: rgba(51, 112, 255, .08); color: var(--kk-accent); font-size: 13px; font-weight: 600; }
h2 { font-size: 17px; margin: 16px 0 8px; font-weight: 600; }
.proof p { color: var(--kk-muted); margin: 0; font-size: 14px; line-height: 1.6; }

.footer { display: flex; justify-content: space-between; padding: 24px 0 32px; }
.footer a { text-decoration: none; transition: color .16s ease-out; }
.footer a:hover { color: var(--kk-accent); }

@media (max-width: 980px) {
  .hero { grid-template-columns: 1fr; padding-bottom: 64px; }
  .hero-copy { max-width: none; }
}

@media (max-width: 680px) {
  .shell { width: min(100% - 32px, 560px); }
  .nav-note { display: none; }
  .hero { padding: 40px 0 56px; }
  h1 { font-size: 32px; }
  .lead { font-size: 16px; margin: 18px 0 26px; }
  .preview-body { grid-template-columns: 68px minmax(0, 1fr); min-height: 300px; }
  .proof { grid-template-columns: 1fr; padding-bottom: 56px; }
}

@media (prefers-reduced-motion: reduce) {
  .download, .proof article { transition: none; }
}