:root {
  /* ========== SURFACE HIERARCHY ========== */
  /* Use these for different depth levels of your UI */
  --color-app-bg: #f4f4f6;          /* L0: App canvas/body - outermost */
  --color-card-bg: #fcfcfd;        /* L1: Cards, modals, floating panels */
  --color-surface-bg: #f4f4f6;  /* L2: Nested sections within cards */
  --color-input-bg: #ffffff;      /* L3: Form input backgrounds */
  --color-header-bg: #0d1d59;    /* Header: Fixed navigation */

  /* Legacy aliases (backward compatibility) */
  --color-bg: var(--color-card-bg);
  --color-bg-secondary: var(--color-surface-bg);

  /* ========== ACCENT COLORS ========== */
  --color-primary: #4262d7;
  --color-secondary: #6746b9;
  --color-accent: #bc5cd6;

  /* ========== TEXT COLORS ========== */
  --color-text: #1f2937;
  --color-text-secondary: #676c7e;
  --color-text-muted: #969aa6;
  --color-text-on-primary: #ffffff;

  /* Contrasting Text Colors (Auto-calculated for WCAG AA) */
  --color-header-text: #ffffff;
  --color-button-text-primary: #ffffff;
  --color-button-text-secondary: #1f2937;

  /* ========== BUTTON COLORS ========== */
  --color-button-primary: #5271e0;
  --color-button-secondary: #e7e4da;
  --color-button-hover: #16339c;

  /* ========== SEMANTIC COLORS ========== */
  --color-success: #b82e4c;
  --color-error: #f0ca42;
  --color-warning: #c725f4;
  --color-info: #7d70db;

  /* ========== SPECIAL COLORS ========== */
  --color-border: #dcdee5;
  --color-divider: #eeeff1;
  --color-rating: #ab5eed;
  --color-focus: #4262d7;

  /* ========== SPACING SCALE ========== */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;

  /* ========== BORDER RADIUS SCALE ========== */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* ========== SHADOWS ========== */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);

  /* ========== TYPOGRAPHY ========== */
  --font-family-base: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;

  /* ========== SCROLLBAR ========== */
  --scrollbar-width: thin;
  --color-scrollbar-thumb: #dcdee5;
  --color-scrollbar-track: #f4f4f6;
}

/* ========== GLOBAL STYLES ========== */
body {
  background-color: var(--color-app-bg);
  color: var(--color-text);
  margin: 0;
  font-family: var(--font-family-base);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-text);
}

/* Headers - Headings inside header elements automatically get contrasting color */
header h1, header h2, header h3, header h4, header h5, header h6 {
  color: var(--color-header-text);
}

/* Links */
a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  color: var(--color-button-hover);
}

/* Buttons */
button {
  cursor: pointer;
  border: none;
  font-family: inherit;
}

button:hover {
  filter: brightness(0.95);
}

/* Input Elements */
input, textarea, select {
  background-color: var(--color-input-bg);
  border: 1px solid var(--color-border);
  color: var(--color-text);
  font-family: inherit;
}

input:focus, textarea:focus, select:focus {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
}

/* Cards */
.card, [class*="Card"] {
  background-color: var(--color-card-bg);
}

/* Dividers */
hr {
  border-color: var(--color-divider);
}

/* ========== SCROLLBAR STYLES ========== */
* {
  scrollbar-width: var(--scrollbar-width);
  scrollbar-color: var(--color-scrollbar-thumb) var(--color-scrollbar-track);
}
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: var(--color-scrollbar-track);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb {
  background: var(--color-scrollbar-thumb);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  filter: brightness(0.85);
}