/* 基础样式：重置、排版、滚动条、通用工具类。 */
*, *::before, *::after { box-sizing: border-box; }
html, body { height: 100%; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.55;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overscroll-behavior-y: none;
}
h1, h2, h3, h4 { margin: 0; font-weight: 650; line-height: 1.3; letter-spacing: -0.01em; }
h1 { font-size: 22px; }
h2 { font-size: 18px; }
h3 { font-size: 15px; }
p { margin: 0; }
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
button, input, textarea, select { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: none; padding: 0; }
img, video, svg { display: block; max-width: 100%; }
ul, ol { margin: 0; padding: 0; list-style: none; }
code, kbd, pre { font-family: var(--font-mono); font-size: 0.92em; }
::selection { background: color-mix(in srgb, var(--brand) 24%, transparent); }
:focus-visible { outline: none; box-shadow: var(--ring); border-radius: var(--radius-sm); }
[hidden] { display: none !important; }

/* 滚动条：桌面细色，移动端隐藏 */
* { scrollbar-width: thin; scrollbar-color: var(--border-2) transparent; }
*::-webkit-scrollbar { width: 8px; height: 8px; }
*::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 999px; border: 2px solid transparent; background-clip: content-box; }
*::-webkit-scrollbar-thumb:hover { background: var(--text-3); background-clip: content-box; }
*::-webkit-scrollbar-track { background: transparent; }

/* 工具类 */
.row { display: flex; align-items: center; gap: var(--space-2); }
.row-tight { display: flex; align-items: center; gap: var(--space-1); }
.col { display: flex; flex-direction: column; }
.between { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.center { display: flex; align-items: center; justify-content: center; }
.grow { flex: 1 1 auto; min-width: 0; }
.wrap { flex-wrap: wrap; }
.gap-1 { gap: var(--space-1); } .gap-2 { gap: var(--space-2); } .gap-3 { gap: var(--space-3); } .gap-4 { gap: var(--space-4); } .gap-5 { gap: var(--space-5); } .gap-6 { gap: var(--space-6); }
.mt-1 { margin-top: var(--space-1); } .mt-2 { margin-top: var(--space-2); } .mt-3 { margin-top: var(--space-3); } .mt-4 { margin-top: var(--space-4); } .mt-6 { margin-top: var(--space-6); }
.mb-1 { margin-bottom: var(--space-1); } .mb-2 { margin-bottom: var(--space-2); } .mb-3 { margin-bottom: var(--space-3); } .mb-4 { margin-bottom: var(--space-4); } .mb-6 { margin-bottom: var(--space-6); }
.text-sm { font-size: 12.5px; }
.text-xs { font-size: 11.5px; }
.text-lg { font-size: 16px; }
.muted { color: var(--text-3); }
.secondary { color: var(--text-2); }
.strong { font-weight: 600; }
.mono { font-family: var(--font-mono); }
.center-text { text-align: center; }
.right { margin-left: auto; }
.truncate { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; min-width: 0; }
.clamp-2 { display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.pointer { cursor: pointer; }
.select-none { user-select: none; }
.full { width: 100%; }
.hidden { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.divider { height: 1px; background: var(--border); border: 0; margin: var(--space-4) 0; }
.divider-vertical { width: 1px; height: 20px; background: var(--border); }
.no-select { user-select: none; -webkit-user-select: none; }
.scroll-area { overflow-y: auto; overscroll-behavior: contain; }

@keyframes fade-in { from { opacity: 0; } to { opacity: 1; } }
@keyframes pop-in { from { opacity: 0; transform: translateY(6px) scale(0.985); } to { opacity: 1; transform: none; } }
@keyframes slide-up { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
@keyframes spin { to { transform: rotate(360deg); } }
@keyframes pulse-dot { 0%, 100% { opacity: 1; } 50% { opacity: 0.35; } }
@keyframes shimmer { from { background-position: -400px 0; } to { background-position: 400px 0; } }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}