* { box-sizing: border-box; }
body { margin: 0; font-family: 'Helvetica', 'Helvetica Neue', Arial, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Noto Sans', 'Microsoft YaHei', sans-serif; background: #f6f7fb; color: #333; }
.site-header { display: flex; justify-content: space-between; align-items: center; padding: 12px 16px; background: #fff; border-bottom: 1px solid #e5e7eb; position: sticky; top: 0; }
.logo { font-weight: 600; }
.nav-right { display: flex; gap: 8px; align-items: center; }
.container { max-width: 1000px; margin: 24px auto; padding: 0 16px; }
.card { background: #fff; border: 1px solid #e5e7eb; border-radius: 8px; margin-bottom: 16px; padding: 16px; }
.file-table { width: 100%; border-collapse: collapse; }
.file-table th, .file-table td { padding: 8px; border-bottom: 1px solid #eee; }
.file-table th { text-align: left; color: #555; }
.btn { display: inline-block; padding: 6px 12px; border: 1px solid #d1d5db; border-radius: 6px; background: #fff; color: #111; text-decoration: none; font-size: 14px; }
.btn:hover { background: #f3f4f6; }
.btn-primary { background: #2563eb; border-color: #2563eb; color: #fff; }
.btn-primary:hover { background: #1d4ed8; }
.btn-danger { background: #ef4444; border-color: #ef4444; color: #fff; }
.btn-sm { font-size: 12px; padding: 4px 8px; }
label { display: block; margin: 8px 0 4px; }
input[type="text"], input[type="email"], input[type="password"] { width: 100%; padding: 8px; border: 1px solid #d1d5db; border-radius: 6px; }
input[type="file"] { margin: 8px 0; }
.checkbox { display: inline-flex; align-items: center; gap: 6px; margin-left: 12px; }
.alert { padding: 8px 12px; border-radius: 6px; margin-bottom: 12px; }
.alert-danger { background: #fee2e2; border: 1px solid #fca5a5; color: #991b1b; }
.hint { color: #6b7280; font-size: 12px; }
.empty { color: #6b7280; }
.welcome { margin-right: 8px; color: #111827; }
.back-to-top-fixed { position: fixed; right: 16px; bottom: 16px; z-index: 1000; display: none; }
.back-to-top-fixed.is-visible { display: inline-block; }