:root {
  --bg: #f2f4f8;
  --card: #ffffff;
  --text: #1c2430;
  --muted: #6b7686;
  --primary: #2f6fed;
  --primary-dark: #2258c7;
  --success: #1f9d61;
  --warning: #d97706;
  --danger: #dc2626;
  --border: #e2e7ef;
  --radius: 12px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}
button {
  font: inherit;
  border: none;
  border-radius: 10px;
  padding: 10px 18px;
  cursor: pointer;
  background: var(--primary);
  color: #fff;
  transition: background .15s, transform .05s;
}
button:active { transform: scale(.97); }
button:disabled { opacity: .55; cursor: not-allowed; }
button.ghost { background: #eef2f9; color: var(--text); }
button.danger { background: var(--danger); }
button.small { padding: 6px 12px; font-size: 13px; border-radius: 8px; }
input[type="text"], input[type="password"], input[type="file"], select, textarea {
  font: inherit;
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  color: var(--text);
}
input:focus, select:focus { outline: 2px solid var(--primary); outline-offset: -1px; }
label { display: block; font-size: 14px; color: var(--muted); margin: 12px 0 6px; }

.hidden { display: none !important; }
.muted { color: var(--muted); }
.toast {
  position: fixed; left: 50%; bottom: 48px; transform: translateX(-50%);
  background: rgba(20, 26, 36, .92); color: #fff; padding: 12px 20px;
  border-radius: 10px; font-size: 15px; z-index: 1000; max-width: 86vw; text-align: center;
  animation: toastIn .2s ease;
}
.toast.error { background: rgba(180, 38, 38, .95); }
@keyframes toastIn { from { opacity: 0; transform: translate(-50%, 10px); } to { opacity: 1; } }
.spinner {
  width: 22px; height: 22px; border: 3px solid rgba(255,255,255,.35);
  border-top-color: #fff; border-radius: 50%; animation: spin .8s linear infinite; display: inline-block;
}
@keyframes spin { to { transform: rotate(360deg); } }