:root {
  --bg: #9dd6f5;
  --card: #ffffff;
  --text: #222;
  --muted: #555;
  --brand: #27c9a7;
  --accent: #f59f00;
  --button: #3b2f2f;
  --shadow: 0 10px 30px rgba(0,0,0,.12);
  --radius: 14px;
  --maxw: 980px;
}
html,body {height:100%;}
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  background-attachment: fixed;
}
.container { max-width: var(--maxw); margin: 24px auto; padding: 0 16px; }
.box { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden; }
.hero {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  align-items: end;
}
.hero img { width: 100%; height: 320px; object-fit: cover; filter: grayscale(30%) contrast(105%); }
.hero .content { position: absolute; inset: 0; display: flex; flex-direction: column; justify-content: flex-end; padding: 28px; color: #fff; }
.hero h1 { font-size: 36px; margin: 0 0 10px; letter-spacing: 1px; }
.hero .sub { font-size: 18px; color: #d6f9f2; }
.hero .action { margin-top: 18px; }
.hero .btn { display: inline-block; background: var(--button); color: #fff; padding: 12px 18px; border-radius: 8px; text-decoration: none; }
.section { margin: 26px 0; padding: 18px 22px; }
.section h2 { margin: 0; font-size: 22px; }
.section-head { display: flex; align-items: center; gap: 12px; justify-content: space-between; }
.download-btn { display: inline-block; background: var(--button); color: #fff; padding: 10px 14px; border-radius: 8px; text-decoration: none; font-size: 14px; white-space: nowrap; }
.download-btn:hover { filter: brightness(1.05); }
.section .tip { color: var(--muted); font-size: 14px; }
.banner-grid { display: grid; grid-template-columns: 1fr; gap: 16px; padding: 18px; }
@media (min-width: 820px) { .banner-grid { grid-template-columns: 1fr 1fr; } }
.adbanner { position: relative; border-radius: 12px; box-shadow: var(--shadow); overflow: hidden; background: var(--card); display: flex; align-items: center; justify-content: center; }
.adbanner img { max-width: 100%;  width: auto; object-fit: contain; object-position: center; display: block; }
.adbanner .tag { position: absolute; right: 8px; bottom: 8px; background: #e63c3c; color: #fff; font-size: 8px; padding: 2px 6px; border-radius: 4px; }
.sites-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; padding: 12px 18px; }
@media (min-width: 820px) { .sites-grid { grid-template-columns: repeat(6, 1fr); } }
.site-cell { display: flex; align-items: center; justify-content: center; height: 48px; border-radius: 10px; background: #f7f7f7; text-decoration: none; color: var(--text); box-shadow: var(--shadow); }
.site-cell:hover { filter: brightness(1.03); }
.footer { text-align: center; color: var(--muted); font-size: 13px; padding: 20px; }
.nav { display: flex; gap: 10px; align-items: center; }
.nav a { color: #fff; text-decoration: none; font-size: 14px; }
.nav a:hover { text-decoration: underline; }