/* ============================================================
   alumnAI — Base styles
   Resets, typography, focus, scrollbar.
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

html {
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: var(--fs-md);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 { margin: 0; font-weight: 600; letter-spacing: -0.01em; line-height: 1.25; }
h1 { font-size: var(--fs-3xl); }
h2 { font-size: var(--fs-2xl); }
h3 { font-size: var(--fs-xl); }
h4 { font-size: var(--fs-lg); }
p { margin: 0; }
a { color: var(--brand-blue-dark); text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: none; padding: 0; cursor: pointer; }
input, select, textarea { font: inherit; color: inherit; }

ul, ol { margin: 0; padding: 0; }

:focus-visible {
  outline: 2px solid var(--brand-blue);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

::selection { background: var(--brand-blue-soft); color: var(--brand-navy); }

/* App init flicker prevention */
.app[data-loading="true"] .view,
.app[data-loading="true"] .topbar,
.app[data-loading="true"] .sidebar {
  opacity: 0;
}
.app .view, .app .topbar, .app .sidebar {
  opacity: 1;
  transition: opacity var(--t) var(--ease);
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* Custom scrollbar (subtle) */
.sidebar::-webkit-scrollbar,
.view::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-thumb,
.view::-webkit-scrollbar-thumb { background: var(--surface-3); border-radius: 999px; }
.sidebar::-webkit-scrollbar-thumb:hover,
.view::-webkit-scrollbar-thumb:hover { background: var(--border-strong); }

/* Utilities */
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
.hidden { display: none !important; }
.text-center { text-align: center; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.mt-1 { margin-top: var(--space-1); }
.mt-2 { margin-top: var(--space-2); }
.mt-3 { margin-top: var(--space-3); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.text-muted { color: var(--text-2); }
.text-dim { color: var(--text-3); }