/* ============================================
   BASE.CSS - Reset, Variables, Typography
   ============================================ */

/* ========== CSS Custom Properties ========== */
:root {
  /* Background Colors */
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --bg-card: #0f3460;
  --bg-surface: #1a1a3e;

  /* Text Colors */
  --text-primary: #edf2f4;
  --text-secondary: #8d99ae;
  --text-muted: #6c757d;

  /* Theme Colors */
  --accent: #e63946;
  --accent-hover: #c1121f;
  --success: #2a9d8f;
  --warning: #e9c46a;
  --info: #457b9d;
  --error: #e63946;

  /* Answer Choice Colors */
  --choice-a: #e63946;
  --choice-b: #457b9d;
  --choice-c: #2a9d8f;
  --choice-d: #e9c46a;

  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.4);

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

/* Light Mode Override */
@media (prefers-color-scheme: light) {
  :root {
    --bg-primary: #f8f9fa;
    --bg-secondary: #e9ecef;
    --bg-card: #ffffff;
    --bg-surface: #f1f3f5;
    --text-primary: #212529;
    --text-secondary: #495057;
    --text-muted: #868e96;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.16);
  }
}

/* Force Dark Mode for Board/Projector */
body.dark-mode {
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --bg-card: #0f3460;
  --bg-surface: #1a1a3e;
  --text-primary: #edf2f4;
  --text-secondary: #8d99ae;
  --text-muted: #6c757d;
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.4);
}

/* ========== Reset ========== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ========== Base Styles ========== */
html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-family);
  line-height: 1.6;
  margin: 0;
  min-height: 100vh;
}

#app {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ========== Typography ========== */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
}

h2 {
  font-size: 2rem;
  margin-bottom: 1.25rem;
}

h3 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
}

h4 {
  font-size: 1.5rem;
  margin-bottom: 0.875rem;
}

h5 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

h6 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

p {
  margin-bottom: 1rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

strong {
  font-weight: 600;
}

/* ========== Scrollbar Styling ========== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--bg-card);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ========== Utility Classes ========== */

/* Text Alignment */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

/* Text Colors */
.text-muted {
  color: var(--text-muted);
}

.text-secondary {
  color: var(--text-secondary);
}

.text-primary {
  color: var(--text-primary);
}

.text-accent {
  color: var(--accent);
}

.text-success {
  color: var(--success);
}

.text-warning {
  color: var(--warning);
}

.text-error {
  color: var(--error);
}

/* Spacing - Margin Top */
.mt-0 {
  margin-top: 0;
}

.mt-1 {
  margin-top: 0.5rem;
}

.mt-2 {
  margin-top: 1rem;
}

.mt-3 {
  margin-top: 1.5rem;
}

.mt-4 {
  margin-top: 2rem;
}

/* Spacing - Margin Bottom */
.mb-0 {
  margin-bottom: 0;
}

.mb-1 {
  margin-bottom: 0.5rem;
}

.mb-2 {
  margin-bottom: 1rem;
}

.mb-3 {
  margin-bottom: 1.5rem;
}

.mb-4 {
  margin-bottom: 2rem;
}

/* Spacing - Margin Left */
.ml-1 {
  margin-left: 0.5rem;
}

.ml-2 {
  margin-left: 1rem;
}

/* Spacing - Margin Right */
.mr-1 {
  margin-right: 0.5rem;
}

.mr-2 {
  margin-right: 1rem;
}

/* Display */
.hidden {
  display: none;
}

.block {
  display: block;
}

.inline-block {
  display: inline-block;
}

/* Flexbox */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.flex-row {
  flex-direction: row;
}

.items-center {
  align-items: center;
}

.items-start {
  align-items: flex-start;
}

.items-end {
  align-items: flex-end;
}

.justify-center {
  justify-content: center;
}

.justify-start {
  justify-content: flex-start;
}

.justify-end {
  justify-content: flex-end;
}

.justify-between {
  justify-content: space-between;
}

.flex-wrap {
  flex-wrap: wrap;
}

.flex-1 {
  flex: 1;
}

/* Gap */
.gap-1 {
  gap: 0.5rem;
}

.gap-2 {
  gap: 1rem;
}

.gap-3 {
  gap: 1.5rem;
}

.gap-4 {
  gap: 2rem;
}

/* Width */
.w-full {
  width: 100%;
}

/* Responsive */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  h3 {
    font-size: 1.5rem;
  }
}