/* Page frame: header, main column, footer, mobile tab bar */
#site-header {
  position: sticky; top: 0; z-index: 30; background: var(--surface);
  border-bottom: 1px solid var(--line); padding-top: env(safe-area-inset-top);
}
.header-inner {
  max-width: var(--maxw); margin: 0 auto; height: var(--header-h);
  display: flex; align-items: center; gap: 28px; padding: 0 24px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 700; font-size: 24px; letter-spacing: -0.03em; }
.brand:hover { text-decoration: none; }
.brand svg { width: 32px; height: 32px; display: block; }
.header-nav { display: flex; gap: 6px; }
.header-nav a {
  padding: 8px 14px; color: var(--ink-2); font-weight: 500; font-size: 14px;
  text-transform: uppercase; letter-spacing: var(--caps); border-radius: var(--r-sm);
}
.header-nav a:hover { color: var(--brand); text-decoration: none; }
.header-nav a.active { color: var(--brand); }
.header-search { margin-left: auto; width: 340px; }
.icon-btn {
  width: 40px; height: 40px; display: inline-grid; place-items: center; flex: none;
  border: 1px solid var(--line-strong); background: var(--surface); border-radius: var(--r-sm); color: var(--ink-2);
}
.icon-btn:hover { color: var(--brand); border-color: var(--brand); }
.icon-btn svg { width: 18px; height: 18px; }

#view { display: block; max-width: var(--maxw); margin: 0 auto; padding: 28px 24px 56px; outline: none; }
.page-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 16px; margin-bottom: 18px; flex-wrap: wrap; }
.page-head p { margin: 4px 0 0; }

#banner .demo-banner {
  background: var(--warn-bg); color: var(--warn-ink); font-size: 13px; text-align: center; padding: 7px 16px;
  border-bottom: 1px solid var(--line);
}
#site-footer { background: var(--surface); border-top: 1px solid var(--line); margin-top: 20px; }
.f-grid { max-width: var(--maxw); margin: 0 auto; padding: 48px 24px 56px; display: grid; grid-template-columns: 2.2fr 1fr 1fr 1fr; gap: 32px; }
.f-brand p { color: var(--ink-2); font-size: 15px; margin: 0 0 16px; line-height: 1.6; }
.f-brand .brand { font-size: 22px; margin-bottom: 16px; }
.f-brand .brand svg { width: 28px; height: 28px; }
.f-brand .f-tag { font-size: 20px; font-weight: 600; color: var(--ink); margin-bottom: 20px; }
.f-brand strong { color: var(--ink); }
.heart { color: #E0245E; }
.f-col h4 { font-size: 17px; margin-bottom: 16px; }
.f-col a, .f-col .f-link, .f-col .f-theme { display: flex; align-items: center; gap: 8px; color: var(--ink-2); font-size: 15.5px; margin-bottom: 12px; background: none; border: 0; padding: 0; }
.f-col a:hover, .f-link:hover, .f-theme:hover { color: var(--brand); text-decoration: none; }
.f-link { background: none; border: 0; padding: 0; color: var(--ink-2); text-decoration: underline dotted; text-underline-offset: 3px; font-size: 15px; }
.f-theme svg { width: 16px; height: 16px; }
@media (max-width: 900px) { .f-grid { grid-template-columns: 1fr 1fr; } .f-brand { grid-column: 1 / -1; } }
#tabbar { display: none; }

@media (max-width: 900px) {
  .header-nav { display: none; }
  .header-search { width: auto; flex: 1; }
}
@media (max-width: 760px) {
  :root { --header-h: 56px; }
  .header-inner { padding: 0 14px; gap: 10px; }
  .brand .wordmark { display: none; }
  #view { padding: 16px 12px calc(var(--tabbar-h) + 32px + env(safe-area-inset-bottom)); }
  .f-grid { padding: 32px 16px calc(var(--tabbar-h) + 32px + env(safe-area-inset-bottom)); }
  h1 { font-size: 24px; }
  #tabbar {
    display: grid; grid-template-columns: repeat(4, 1fr);
    position: fixed; left: 0; right: 0; bottom: 0; z-index: 30;
    height: calc(var(--tabbar-h) + env(safe-area-inset-bottom));
    padding-bottom: env(safe-area-inset-bottom);
    background: var(--surface); border-top: 1px solid var(--line);
  }
  #tabbar a {
    display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px;
    color: var(--ink-3); font-size: 11px; font-weight: 500;
  }
  #tabbar a:hover { text-decoration: none; }
  #tabbar a.active { color: var(--brand); }
  #tabbar svg { width: 22px; height: 22px; }
}