/* =========================================================
   ANTARK ENERGY — Global styles
   Clean, minimalist, Tesla/Lucid-inspired
   ========================================================= */

:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --bg-dark: #0a0a0a;
  --text: #0a0a0a;
  --text-muted: #5a5a5a;
  --text-light: #8a8a8a;
  --line: #e5e5e5;
  --accent: #1b4b8a;       /* antark blue */
  --accent-dark: #123461;
  --max: 1280px;
  --radius: 4px;
  --nav-h: 68px;
}

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.55;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

/* ---------- Layout ---------- */
.container { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
.section { padding: 96px 0; }
.section-sm { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }
.section-dark { background: var(--bg-dark); color: #fff; }

/* ---------- Typography ---------- */
h1, h2, h3, h4 { font-weight: 500; letter-spacing: -0.02em; line-height: 1.15; color: var(--text); }
.section-dark h1, .section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }

h1 { font-size: clamp(2.5rem, 6vw, 5rem); font-weight: 600; }
h2 { font-size: clamp(2rem, 4vw, 3.25rem); font-weight: 500; }
h3 { font-size: clamp(1.5rem, 2.5vw, 2rem); font-weight: 500; }
h4 { font-size: 1.125rem; font-weight: 600; letter-spacing: 0; }

p { color: var(--text-muted); font-size: 1.0625rem; }
.section-dark p { color: #c7c7c7; }

.eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 16px;
}
.section-dark .eyebrow { color: #7aa8d9; }

.lead { font-size: 1.25rem; color: var(--text-muted); max-width: 720px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 14px 32px;
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  border-radius: 999px;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  white-space: nowrap;
}
.btn-primary { background: var(--text); color: #fff; }
.btn-primary:hover { background: var(--accent); }
.btn-outline { border-color: var(--text); color: var(--text); }
.btn-outline:hover { background: var(--text); color: #fff; }
.btn-light { background: #fff; color: var(--text); }
.btn-light:hover { background: var(--accent); color: #fff; }
.btn-ghost-light { border: 1px solid rgba(255,255,255,0.5); color: #fff; }
.btn-ghost-light:hover { background: #fff; color: var(--text); }

.btn-row { display: flex; gap: 12px; flex-wrap: wrap; }

/* ---------- Navigation ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
  z-index: 100;
  transition: background 0.3s;
}
.nav-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-weight: 600; font-size: 1.125rem; letter-spacing: -0.01em;
}
.nav-logo img { height: 28px; width: auto; }
.nav-logo span { color: var(--text); }

.nav-links { display: flex; gap: 32px; list-style: none; }
.nav-links a {
  font-size: 0.9375rem;
  color: var(--text);
  font-weight: 500;
  transition: color 0.2s;
  position: relative;
}
.nav-links a:hover, .nav-links a.active { color: var(--accent); }

.nav-cta { display: flex; align-items: center; gap: 12px; }

.nav-toggle {
  display: none;
  width: 28px; height: 28px;
  position: relative;
}
.nav-toggle span {
  display: block;
  position: absolute;
  left: 0;
  width: 100%; height: 2px;
  background: var(--text);
  transition: transform 0.3s, opacity 0.3s, top 0.3s;
}
.nav-toggle span:nth-child(1) { top: 8px; }
.nav-toggle span:nth-child(2) { top: 14px; }
.nav-toggle span:nth-child(3) { top: 20px; }
.nav-toggle.open span:nth-child(1) { top: 14px; transform: rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { top: 14px; transform: rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  height: 100vh;
  min-height: 640px;
  max-height: 900px;
  background: #0a0a0a;
  color: #fff;
  overflow: hidden;
  display: flex;
  align-items: flex-end;
}
.hero-bg {
  position: absolute; inset: 0;
  background-size: cover;
  background-position: center;
  z-index: 0;
}
.hero-bg::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,0.1) 0%, rgba(0,0,0,0) 40%, rgba(0,0,0,0.7) 100%);
}
.hero-content {
  position: relative; z-index: 2;
  width: 100%;
  padding: 0 24px 80px;
  max-width: var(--max);
  margin: 0 auto;
  text-align: center;
}
.hero h1 { color: #fff; margin-bottom: 16px; }
.hero-tag {
  font-size: clamp(0.95rem, 1.5vw, 1.125rem);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.85);
  margin-bottom: 8px;
  font-weight: 400;
}
.hero-sub {
  font-size: clamp(1rem, 1.5vw, 1.25rem);
  color: rgba(255,255,255,0.85);
  margin-bottom: 36px;
  font-weight: 300;
}
.hero .btn-row { justify-content: center; }

/* ---------- Page hero (smaller, inner pages) ---------- */
.page-hero {
  padding: calc(var(--nav-h) + 80px) 0 64px;
  background: var(--bg-alt);
  text-align: center;
}
.page-hero h1 { font-size: clamp(2.25rem, 4.5vw, 4rem); margin-bottom: 16px; }
.page-hero p { font-size: 1.25rem; max-width: 640px; margin: 0 auto; }

/* ---------- Feature grid ---------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 48px; }

.feature {
  padding: 0;
}
.feature-num {
  font-size: 3rem;
  font-weight: 300;
  color: var(--accent);
  display: block;
  margin-bottom: 16px;
  letter-spacing: -0.04em;
}
.feature h3 { margin-bottom: 12px; }
.feature p { font-size: 1rem; }

/* ---------- Stat row ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding: 48px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.section-dark .stats { border-color: #222; }
.stat { text-align: center; }
.stat-num {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--text);
  line-height: 1;
}
.section-dark .stat-num { color: #fff; }
.stat-label {
  font-size: 0.8125rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-top: 8px;
}

/* ---------- Split section ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 0;
}
.split-content { padding: 96px 64px; }
.split-media { aspect-ratio: 4/3; background: #eee; background-size: cover; background-position: center; }
.split.reverse .split-content { order: 2; }
.split.reverse .split-media { order: 1; }

/* ---------- Spec table ---------- */
.specs { border-top: 1px solid var(--line); }
.spec-group { border-bottom: 1px solid var(--line); padding: 40px 0; }
.spec-group h4 {
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-light);
  margin-bottom: 24px;
  font-weight: 600;
}
.spec-row {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 24px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.9375rem;
}
.spec-row:last-child { border-bottom: none; }
.spec-row dt { color: var(--text-muted); }
.spec-row dd { color: var(--text); font-weight: 500; }

/* ---------- Variant card ---------- */
.variants-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.variant-card {
  background: var(--bg);
  border: 1px solid var(--line);
  padding: 32px 24px;
  text-align: center;
  transition: border-color 0.2s, transform 0.2s;
}
.variant-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.variant-card h3 { font-size: 1.375rem; margin-bottom: 6px; }
.variant-card p { font-size: 0.875rem; margin: 0; }

/* ---------- CTA band ---------- */
.cta-band {
  padding: 80px 24px;
  text-align: center;
  background: var(--bg-dark);
  color: #fff;
}
.cta-band h2 { color: #fff; margin-bottom: 16px; }
.cta-band p { color: #c7c7c7; margin: 0 auto 32px; max-width: 580px; }

/* ---------- Form ---------- */
.form {
  max-width: 640px;
  margin: 0 auto;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 16px; }
.form-field { margin-bottom: 16px; }
.form-field label {
  display: block;
  font-size: 0.8125rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.form-field input,
.form-field select,
.form-field textarea {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 1rem;
  font-family: inherit;
  background: #fff;
  color: var(--text);
  transition: border-color 0.2s;
}
.form-field input:focus,
.form-field select:focus,
.form-field textarea:focus {
  outline: none;
  border-color: var(--accent);
}
.form-field textarea { resize: vertical; min-height: 120px; }

/* ---------- Footer ---------- */
.footer {
  background: #0a0a0a;
  color: #b5b5b5;
  padding: 64px 0 32px;
  font-size: 0.875rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-brand img { height: 36px; margin-bottom: 16px; }
.footer-brand p { color: #8a8a8a; max-width: 320px; font-size: 0.875rem; }
.footer h5 {
  color: #fff;
  font-size: 0.8125rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 20px;
}
.footer ul { list-style: none; }
.footer li { margin-bottom: 10px; }
.footer a { color: #b5b5b5; transition: color 0.2s; }
.footer a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #222;
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  color: #666;
  font-size: 0.8125rem;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- Gallery strip ---------- */
.gallery-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 4px;
}
.gallery-strip .tile {
  aspect-ratio: 4/3;
  background-size: cover;
  background-position: center;
  background-color: #222;
}

/* ---------- Timeline / value list ---------- */
.value-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2px;
  background: var(--line);
  border: 1px solid var(--line);
}
.value-list > div {
  background: #fff;
  padding: 32px;
}
.value-list h4 {
  font-size: 1.0625rem;
  margin-bottom: 8px;
  color: var(--accent);
}
.value-list p { font-size: 0.9375rem; margin: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .section { padding: 72px 0; }
  .grid-3 { grid-template-columns: 1fr; gap: 40px; }
  .grid-2 { grid-template-columns: 1fr; gap: 32px; }
  .variants-grid { grid-template-columns: repeat(2, 1fr); }
  .value-list { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; }
  .split-content { padding: 56px 24px; }
  .split.reverse .split-content { order: 2; }
  .split.reverse .split-media { order: 1; }
  .stats { grid-template-columns: repeat(2, 1fr); gap: 32px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .form-row { grid-template-columns: 1fr; }

  .nav-links {
    position: fixed;
    top: var(--nav-h); left: 0; right: 0;
    background: #fff;
    flex-direction: column;
    padding: 24px;
    gap: 0;
    border-bottom: 1px solid var(--line);
    transform: translateY(-120%);
    transition: transform 0.3s ease;
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links li { padding: 14px 0; border-bottom: 1px solid var(--line); }
  .nav-links li:last-child { border-bottom: none; }
  .nav-toggle { display: block; }
  .nav-cta .btn { display: none; }
}

@media (max-width: 600px) {
  .hero { min-height: 560px; }
  .hero-content { padding-bottom: 56px; }
  .footer-grid { grid-template-columns: 1fr; }
  .spec-row { grid-template-columns: 1fr; gap: 4px; }
  .spec-row dt { font-size: 0.8125rem; }
}