:root { /* Brand colors (from spec) */ --c-primary: #2563EB; /* 科技蓝 */ --c-primary-600: #1d4ed8; --c-primary-50: #eff6ff; --c-ai: #7C3AED; /* AI 紫 */ --c-ai-50: #f5f3ff; --c-success: #10B981; --c-warning: #F59E0B; --c-danger: #EF4444; /* Light theme surfaces */ --bg: #F8FAFC; --bg-elevated: #ffffff; --bg-subtle: #f1f5f9; --bg-hover: #eef2f7; --border: #e2e8f0; --border-strong: #cbd5e1; --text: #0f172a; --text-secondary: #475569; --text-muted: #94a3b8; --shadow-sm: 0 1px 2px rgba(15,23,42,.06); --shadow-md: 0 4px 14px rgba(15,23,42,.08); --shadow-lg: 0 12px 32px rgba(15,23,42,.12); /* Difficulty colors */ --d-easy: #10B981; --d-mid: #3B82F6; --d-high: #F59E0B; --d-expert: #EF4444; /* Sizing */ --sidebar-w: 240px; --topbar-h: 60px; --radius-sm: 8px; --radius: 12px; --radius-lg: 16px; --font-zh: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", sans-serif; --font-mono: "JetBrains Mono", "Fira Code", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace; } /* Dark theme via [data-theme="dark"] on */ html[data-theme="dark"] { --bg: #0F172A; --bg-elevated: #1e293b; --bg-subtle: #172033; --bg-hover: #243044; --border: #2d3a4f; --border-strong: #3b4a61; --text: #e2e8f0; --text-secondary: #aeb9c9; --text-muted: #64748b; --shadow-sm: 0 1px 2px rgba(0,0,0,.4); --shadow-md: 0 4px 14px rgba(0,0,0,.45); --shadow-lg: 0 12px 32px rgba(0,0,0,.55); --c-primary-50: #1e293b; --c-ai-50: #241a3a; --bg-hover-2: #1e293b; } html[data-theme="dark"] body { background: var(--bg); color: var(--text); }