:root {
  --green: #2AAE67;
  --accent: #3DCA7E;
  --bg: #fafeff;
  --bg-page: #f6f6f6;
  --text-main: #474C50;
  --text-muted: #888E93;
  --text-secondary: #ADBCC9;
  --white: #ffffff;
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Noto Sans CJK SC", "Microsoft YaHei", sans-serif;
  background: var(--bg-page);
  color: var(--text-main);
}
.container { max-width: 1120px; margin: 0 auto; padding: 0 16px; }
.row { display: flex; }
.center { align-items: center; }
.between { justify-content: space-between; }

.topbar {
  position: sticky;
  top: 0;
  height: 2.5625rem; /* 约等于 h-82rpx */
  background: var(--green);
  color: var(--white);
  display: flex;
  align-items: center;
}
.brand { font-size: 22px; font-weight: 600; margin: 0 0 0 10px; letter-spacing: 0.09375rem; line-height: 2.40625rem; }
.subtitle { font-size: 14px; opacity: .9; line-height: 1.25rem; }
.logo-img { width: 32px; height: 32px; object-fit: contain; }
.row { gap: 10px; }
.divider { height: 2px; background: var(--accent); }

.main { background: var(--bg); }
.hero { display: flex; flex-direction: column; align-items: center; padding: 2.25rem 1rem 1rem; background: url('../img/top_bg.png') no-repeat center top; background-size: 820px auto; }
.video-box { width: 78%; max-width: 880px; height: 10.8125rem; border-radius: 12px; overflow: hidden; background: #000; display: grid; place-items: center; box-shadow: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -2px rgba(0,0,0,.1); }
.video-box video { width: 100%; height: 100%; object-fit: cover; }
.video-fallback { color: var(--text-secondary); padding: 8px 12px; }
 
/* 背景图改为直接作为 .hero 背景，不再使用独立图片元素 */

.overview { padding: 24px 16px; }
.paragraph { font-size: 16px; line-height: 1.8; color: #202020; }

.features { background: #F2FEF7; padding: 32px 0; }
.title { font-size: 22px; font-weight: 700; text-align: center; margin: 0; line-height: 2; color: #474C50; }
.subtitle-en { text-align: center; color: var(--text-secondary); }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 20px; }
.card { background: var(--white); border-radius: 12px; padding: 16px; box-shadow: 0 4px 12px rgba(0,0,0,0.08); display: grid; grid-template-rows: auto auto 1fr; }
.feature-icon { width: 80px; height: 80px; object-fit: contain; }
.card-title { font-size: 18px; line-height: 2.2; margin: 8px 0 4px; color: #474C50; }
.card-hint { font-size: 14px; line-height: 1.6; color: #888E93; }

.contact { padding: 24px 0; gap: 8px; }
.muted { color: var(--text-muted); font-size: 14px; }
.link { color: #3F6BF0; text-decoration: underline; font-size: 14px; }
.btn-link { background: none; border: none; color: #3F6BF0; cursor: pointer; font-size: 14px; }

.cta { position: fixed; left: 0; right: 0; bottom: 0; display: grid; place-items: center; height: 120px; background: var(--green); }
.download-btn { position: relative; display: inline-flex; align-items: center; justify-content: center; gap: 10px; height: 2.5rem; width: 13.5rem; border-radius: 1.8125rem; background: var(--white); color: #07C160; font-size: 1rem; border: none; cursor: pointer; }
.android-img { position: absolute; left: 0.75rem; top: 50%; transform: translateY(-50%); width: 1.25rem; height: 1.25rem; object-fit: contain; }
.download-btn .label { display: flex; align-items: center; justify-content: center; width: 100%; height: 100%; }

.modal[hidden] { display: none; }
.modal { position: fixed; inset: 0; z-index: 1000; }
.modal-mask { position: absolute; inset: 0; background: rgba(0,0,0,.77); }
.dialog { position: relative; z-index: 1001; width: min(500px, 94%); margin: 15% auto; background: #fff; border-radius: 12px; padding: 0 0 20px; text-align: center; box-shadow: 0 10px 30px rgba(0,0,0,.12); overflow: hidden; }
.dialog-title { margin: 0; padding: 40px 16px 10px; font-size: 20px; font-weight: 700; color: #333; line-height: 1.4; word-break: break-word; }
.down-colse { width: min(480px, 94%); padding-top: 10px; margin: 0 auto; text-align: right; }
.down-colse img { width: 27px; height: 27px; cursor: pointer; }
.down-title { font-size: 20px; color: #333; font-weight: bold; padding-top: 10px; }
.option.down-btn { width: 390px; height: 66px; margin: 20px auto 0; border-radius: 4px; background-color: #07c160; line-height: 1.2; font-size: 14px; color: #ffffff; cursor: pointer; display: flex; align-items: center; padding: 0; }
.option.down-btn:hover { background-color: #2AAE67; }
.down-img { padding-left: 20px; padding-top: 12px; }
.down-img img { width: 33px; height: 33px; margin-top: 5px; }
.down-right { text-align: left; padding-left: 5px; white-space: normal; word-break: break-word; }
.btn-title { font-size: 16px; padding-top: 10px; }
.btn-desc { font-size: 12px; }

.toast { position: fixed; left: 50%; bottom: 140px; transform: translateX(-50%); background: rgba(0,0,0,.75); color: #fff; padding: 8px 12px; border-radius: 8px; }

@media (max-width: 960px) {
  .grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .grid { grid-template-columns: 1fr; }
  .download-btn { width: 86%; }
  .video-box { width: 100%; height: 10.8125rem; }
  /* 背景图尺寸在小屏以contain渲染 */
  .hero { background-size: 100% auto; }
  .option.down-btn { width: min(390px, 92%); }
}