/* ============================================================
   BASE — reset, document defaults, typography, utilities
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--navbar-height) + var(--space-6));
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-feature-settings: "kern", "liga", "calt";
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color var(--dur-base) var(--ease-out),
              color var(--dur-base) var(--ease-out);
}

/* Theme transition — only enable after first paint to avoid flash */
.theme-ready *, .theme-ready *::before, .theme-ready *::after {
  transition: background-color var(--dur-base) var(--ease-out),
              border-color var(--dur-base) var(--ease-out),
              color var(--dur-base) var(--ease-out);
}

img, svg, video, canvas { display: block; max-width: 100%; }
img { height: auto; }

a { color: inherit; text-decoration: none; }
button, input, textarea, select { font: inherit; color: inherit; }
button { background: none; border: none; cursor: pointer; }
ul, ol { list-style: none; }

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

::selection {
  background: var(--color-accent);
  color: var(--color-accent-text);
}

/* ----- Headings ----- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  color: var(--color-text);
}

/* Arabic-script fonts shouldn't use negative tracking — can clip connecting glyphs */
[dir="rtl"] h1,
[dir="rtl"] h2,
[dir="rtl"] h3,
[dir="rtl"] h4,
[dir="rtl"] h5,
[dir="rtl"] h6,
[dir="rtl"] .navbar__brand,
[dir="rtl"] .navbar__brand-mark {
  letter-spacing: 0;
}

h1 { font-size: clamp(2.5rem, 5vw + 1rem, var(--text-6xl)); letter-spacing: var(--tracking-tighter); }
h2 { font-size: clamp(2rem, 3vw + 1rem, var(--text-4xl)); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p { line-height: var(--leading-normal); }

strong { font-weight: 600; color: var(--color-text); }

/* ----- Layout primitives ----- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.section {
  padding-block: clamp(var(--space-12), 5vw, var(--space-20));
}

.section--tight { padding-block: clamp(var(--space-10), 3vw, var(--space-16)); }

.section__header {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-10);
  max-width: 60ch;
}

.section__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
  color: var(--color-accent-strong);
  font-weight: 600;
}

.section__eyebrow::before {
  content: "";
  width: 24px;
  height: 1px;
  background: var(--color-accent);
}

.section__title {
  font-size: clamp(1.75rem, 3vw + 0.5rem, var(--text-3xl));
  font-weight: 600;
}

.section__lead {
  color: var(--color-text-muted);
  font-size: var(--text-md);
  max-width: 56ch;
}

/* ----- Utility ----- */
.text-muted { color: var(--color-text-muted); }
.text-accent { color: var(--color-accent); }
.text-mono { font-family: var(--font-mono); }

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

.skip-link {
  position: fixed;
  top: var(--space-3);
  inset-inline-start: var(--space-3);
  z-index: var(--z-overlay);
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  transform: translateY(-150%);
  transition: transform var(--dur-base) var(--ease-out);
}
.skip-link:focus { transform: translateY(0); }

/* ----- Scroll reveal animations ----- */
[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--dur-slow) var(--ease-out),
              transform var(--dur-slow) var(--ease-out);
  transition-delay: var(--reveal-delay, 0ms);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  [data-reveal] { opacity: 1; transform: none; }
}

/* ----- Decorative grid background (subtle) ----- */
.grid-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--color-border) 1px, transparent 1px),
    linear-gradient(to bottom, var(--color-border) 1px, transparent 1px);
  background-size: 80px 80px;
  background-position: center;
  mask-image: radial-gradient(ellipse at center, black 0%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 0%, transparent 75%);
  opacity: 0.4;
}

/* Subtle accent glow in hero */
.glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  z-index: -1;
}