/* ------------------------------------------------------------------
   Design tokens
   Background values are sampled from the hero footage so the page and
   the engine film share one continuous surface.
------------------------------------------------------------------ */
:root {
  --color-bg: #00030b;
  --color-bg-raised: #050b18;
  --color-navy: #001022;
  --color-text: #eef1f5;
  --color-text-muted: rgb(238 241 245 / 0.62);
  --color-line: rgb(238 241 245 / 0.14);
  --color-gold: #d2ac68;
  --color-gold-soft: #e4c999;

  --font-sans: "Vazirmatn", system-ui, -apple-system, "Segoe UI", sans-serif;

  --gutter: clamp(20px, 5.5vw, 96px);
  --header-h: 92px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);

  color-scheme: dark;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

/* In-page links (the hero CTA) glide through the film rather than cut. */
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

[id] { scroll-margin-top: var(--header-h); }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

img, svg, canvas { display: block; max-width: 100%; }
h1, h2, h3, p { margin: 0; }
a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 4px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip-link {
  position: absolute;
  inset-inline-start: 16px;
  top: -100px;
  z-index: 100;
  padding: 8px 16px;
  background: var(--color-text);
  color: var(--color-bg);
}
.skip-link:focus { top: 16px; }

.container {
  width: 100%;
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ------------------------------------------------------------------
   Shared atoms
------------------------------------------------------------------ */
.eyebrow {
  font-size: 12px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--color-gold);
}

/* LTR eyebrows sit on the RTL column's start (right) edge; cancel the
   trailing tracking so the edge lines up with the Persian text. */
.eyebrow[dir="ltr"] {
  text-align: right;
  margin-right: -0.32em;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-height: 52px;
  padding: 0 28px;
  border: 1px solid transparent;
  border-radius: 999px;
  font: 500 15px/1 var(--font-sans);
  text-decoration: none;
  transition: background-color 0.35s var(--ease-out), color 0.35s var(--ease-out),
              border-color 0.35s var(--ease-out);
}
.button__icon {
  width: 16px;
  height: 16px;
  transition: transform 0.35s var(--ease-out);
}
.button:hover .button__icon { transform: translateX(-4px); }

.button--primary {
  background: var(--color-text);
  color: var(--color-bg);
}
.button--primary:hover {
  background: var(--color-gold-soft);
}

/* ------------------------------------------------------------------
   Header — overlays the hero. A soft top scrim (not a bar) keeps the
   links legible over the bright chrome in the top-right of the film.
------------------------------------------------------------------ */
.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  height: var(--header-h);
  transition: background-color 0.4s var(--ease-out), border-color 0.4s var(--ease-out);
  border-bottom: 1px solid transparent;
}
.site-header::before {
  content: "";
  position: absolute;
  inset: 0 0 -60px;
  z-index: -1;
  pointer-events: none;
  background: linear-gradient(to bottom, rgb(0 3 11 / 0.72), rgb(0 3 11 / 0));
  transition: opacity 0.4s var(--ease-out);
}
.site-header.is-solid {
  background: rgb(0 3 11 / 0.92);
  border-bottom-color: var(--color-line);
}
.site-header.is-solid::before { opacity: 0; }

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.site-header__brand {
  display: block;
  flex: none;
}
/* Three lines of lettering: below ~56px tall they stop being readable. */
.site-header__brand img {
  width: auto;
  height: 58px;
}

.site-nav {
  display: flex;
  gap: clamp(20px, 3vw, 44px);
  margin: 0;
  padding: 0;
  list-style: none;
}
.site-nav a {
  font-size: 15px;
  text-decoration: none;
  color: var(--color-text);
  text-shadow: 0 1px 12px rgb(0 3 11 / 0.6);
  opacity: 0.86;
  transition: opacity 0.3s;
}
.site-nav a:hover { opacity: 1; }

@media (max-width: 560px) {
  :root { --header-h: 72px; }
  .site-header__brand img { height: 46px; }
  .site-nav { gap: 18px; }
  .site-nav a { font-size: 14px; }
}

/* ------------------------------------------------------------------
   Sections after the hero
------------------------------------------------------------------ */
.section {
  position: relative;
  padding-block: clamp(96px, 14vw, 180px);
}

.section__head {
  display: grid;
  gap: 20px;
  margin-bottom: clamp(48px, 7vw, 96px);
}

.section__title {
  font-size: clamp(36px, 4.2vw, 64px);
  font-weight: 300;
  line-height: 1.15;
}

.site-footer {
  padding-block: 48px;
  border-top: 1px solid var(--color-line);
  color: var(--color-text-muted);
  font-size: 14px;
}