:root {
  --color-bg: #f8f9fa;
  --color-bg-sidebar: #ffffff;
  --color-surface: #ffffff;
  --color-surface-elevated: #ffffff;
  --color-border: #e5e7eb;
  --color-border-card: #e5e7eb;

  --color-text: #1a1a1a;
  --color-text-muted: #6c757d;
  --color-text-faint: #9ca3af;

  --color-primary: #0f172a;
  --color-primary-text: #ffffff;
  --color-primary-hover: #1e293b;

  --color-search-bg: #f1f3f5;
  --color-sidebar-active: #f1f3f5;
  --color-sidebar-indicator: #3b82f6;

  --color-tag-bg: #f1f3f5;
  --color-tag-text: #4b5563;

  --color-star: #f59e0b;
  --color-star-empty: #9ca3af;

  --color-success: #059669;
  --color-danger: #dc2626;
  --color-danger-bg: rgba(220, 38, 38, 0.08);

  --tag-dot-1: #93c5fd;
  --tag-dot-2: #a5b4fc;
  --tag-dot-3: #9ca3af;
  --tag-dot-4: #fcd34d;
  --tag-dot-5: #86efac;

  --font-family: "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --font-size-base: 1.4rem;
  --font-size-sm: 1.2rem;
  --font-size-md: 1.5rem;
  --font-size-lg: 1.7rem;
  --font-size-xl: 2rem;

  --spacing-xs: 0.6rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.6rem;
  --spacing-lg: 2.4rem;
  --spacing-xl: 3.2rem;

  --sidebar-width: 20rem;
  --topbar-height: 6.4rem;

  --radius-sm: 0.6rem;
  --radius-md: 0.8rem;
  --radius-lg: 1rem;
  --radius-full: 999rem;

  --shadow-card: 0 0.1rem 0.3rem rgba(0, 0, 0, 0.04);
  --shadow-modal: 0 1.6rem 4.8rem rgba(0, 0, 0, 0.18);

  --transition: 0.2s ease;
}

[data-theme="dark"] {
  --color-bg: #1a1f2b;
  --color-bg-sidebar: #151921;
  --color-surface: #212836;
  --color-surface-elevated: #212836;
  --color-border: #2d3548;
  --color-border-card: #2d3548;

  --color-text: #f8fafc;
  --color-text-muted: #94a3b8;
  --color-text-faint: #64748b;

  --color-primary: #ffffff;
  --color-primary-text: #0f172a;
  --color-primary-hover: #e2e8f0;

  --color-search-bg: #151921;
  --color-sidebar-active: rgba(255, 255, 255, 0.06);
  --color-sidebar-indicator: #94a3b8;

  --color-tag-bg: #2d3548;
  --color-tag-text: #cbd5e1;

  --color-star: #fbbf24;
  --color-star-empty: #64748b;

  --shadow-card: 0 0.1rem 0.2rem rgba(0, 0, 0, 0.2);
}

html {
  font-size: 62.5%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.5;
  min-height: 100vh;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}