/* ============================================
   DriveTrain Design System v2
   Aesthetic: Automotive HUD / Racing Dashboard
   Dark, glowing, glass, perspective depth
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;500;600;700;800;900&family=Sora:wght@300;400;500;600;700&display=swap');

/* --- Tokens --- */
:root {
  --dt-green: #2AFF80;
  --dt-green-mid: #1ecc66;
  --dt-green-dim: rgba(42, 255, 128, 0.12);
  --dt-green-glow: rgba(42, 255, 128, 0.5);
  --dt-blue: #2A7FFF;
  --dt-blue-dim: rgba(42, 127, 255, 0.12);
  --dt-blue-glow: rgba(42, 127, 255, 0.5);
  --dt-cyan: #00E5FF;
  --dt-red: #FF3B3B;
  --dt-yellow: #FFD93D;
  --dt-orange: #FF8A2A;

  --dt-bg-deep: #050508;
  --dt-bg: #0a0b10;
  --dt-surface: rgba(16, 18, 27, 0.7);
  --dt-surface-solid: #10121b;
  --dt-surface-raised: rgba(22, 25, 38, 0.8);
  --dt-surface-hover: rgba(30, 34, 52, 0.9);
  --dt-glass: rgba(16, 18, 27, 0.55);
  --dt-glass-border: rgba(255, 255, 255, 0.06);
  --dt-border: rgba(255, 255, 255, 0.05);
  --dt-border-bright: rgba(255, 255, 255, 0.1);

  --dt-text: #e4e6ef;
  --dt-text-bright: #f8f9ff;
  --dt-text-dim: #8a8ea8;
  --dt-text-muted: #4a4e68;

  --dt-font-display: 'Orbitron', monospace;
  --dt-font-body: 'Sora', sans-serif;

  --dt-radius: 12px;
  --dt-radius-sm: 8px;
  --dt-radius-lg: 20px;
  --dt-radius-xl: 28px;

  --dt-ease: cubic-bezier(0.16, 1, 0.3, 1);
  --dt-transition: 0.3s var(--dt-ease);
  --dt-max-width: 1200px;
  --dt-gutter: 24px;
}

/* --- Reset --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: var(--dt-font-body);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.65;
  color: var(--dt-text);
  background: var(--dt-bg-deep);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* === ATMOSPHERIC BACKGROUND === */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 0;
  background:
    /* Top spotlight */
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(42, 127, 255, 0.08) 0%, transparent 60%),
    /* Bottom horizon glow */
    radial-gradient(ellipse 100% 40% at 50% 110%, rgba(42, 255, 128, 0.04) 0%, transparent 50%),
    /* Ambient center */
    radial-gradient(circle at 50% 50%, rgba(10, 11, 16, 0) 0%, var(--dt-bg-deep) 70%);
  pointer-events: none;
}

/* Perspective grid floor */
body::after {
  content: '';
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%) perspective(400px) rotateX(55deg);
  width: 200vw;
  height: 70vh;
  z-index: 0;
  background:
    repeating-linear-gradient(90deg, rgba(42, 127, 255, 0.04) 0px, rgba(42, 127, 255, 0.04) 1px, transparent 1px, transparent 80px),
    repeating-linear-gradient(0deg, rgba(42, 255, 128, 0.03) 0px, rgba(42, 255, 128, 0.03) 1px, transparent 1px, transparent 80px);
  pointer-events: none;
  mask-image: linear-gradient(to top, rgba(0,0,0,0.5) 0%, transparent 80%);
  -webkit-mask-image: linear-gradient(to top, rgba(0,0,0,0.5) 0%, transparent 80%);
}

/* Film grain overlay */
.dt-page::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 1;
  opacity: 0.3;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
}

/* --- Typography --- */
h1, h2, h3, h4 {
  font-family: var(--dt-font-display);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.04em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  text-transform: uppercase;
  background: linear-gradient(135deg, var(--dt-green) 0%, var(--dt-cyan) 50%, var(--dt-blue) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  filter: drop-shadow(0 0 30px var(--dt-green-glow));
}

h2 {
  font-size: clamp(1.3rem, 3vw, 1.9rem);
  font-weight: 700;
  color: var(--dt-text-bright);
}

h3 {
  font-size: clamp(0.95rem, 2vw, 1.2rem);
  font-weight: 600;
  color: var(--dt-cyan);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

p { max-width: 60ch; }

a {
  color: var(--dt-blue);
  text-decoration: none;
  transition: all var(--dt-transition);
}
a:hover { color: var(--dt-green); }

/* --- Layout --- */
.dt-page {
  position: relative;
  z-index: 2;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.dt-container {
  width: 100%;
  max-width: var(--dt-max-width);
  margin: 0 auto;
  padding: 0 var(--dt-gutter);
}

.dt-main { flex: 1; padding: 40px 0 60px; }

/* === NAVIGATION === */
.dt-nav {
  position: sticky;
  top: 0;
  z-index: 200;
  background: rgba(5, 5, 8, 0.75);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  border-bottom: 1px solid var(--dt-glass-border);
}

.dt-nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.dt-logo {
  font-family: var(--dt-font-display);
  font-weight: 800;
  font-size: 1.25rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: all var(--dt-transition);
  background: linear-gradient(135deg, var(--dt-green), var(--dt-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.dt-logo:hover {
  filter: drop-shadow(0 0 16px var(--dt-green-glow));
}

.dt-logo-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--dt-green), var(--dt-blue));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  -webkit-text-fill-color: #000;
  font-weight: 900;
  box-shadow: 0 0 20px var(--dt-green-dim);
  position: relative;
  overflow: hidden;
}

.dt-logo-mark::after {
  content: '';
  position: absolute;
  inset: 1px;
  border-radius: 9px;
  background: linear-gradient(135deg, rgba(255,255,255,0.2), transparent);
}

.dt-nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.dt-nav-links a {
  font-family: var(--dt-font-display);
  font-weight: 600;
  font-size: 0.72rem;
  color: var(--dt-text-dim);
  padding: 10px 18px;
  border-radius: var(--dt-radius-sm);
  transition: all var(--dt-transition);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  position: relative;
}

.dt-nav-links a::before {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 20px;
  height: 2px;
  background: var(--dt-green);
  border-radius: 1px;
  transition: transform var(--dt-transition);
  box-shadow: 0 0 8px var(--dt-green-glow);
}

.dt-nav-links a:hover {
  color: var(--dt-text-bright);
  background: rgba(255,255,255,0.03);
}

.dt-nav-links a.active {
  color: var(--dt-green);
}

.dt-nav-links a.active::before,
.dt-nav-links a:hover::before {
  transform: translateX(-50%) scaleX(1);
}

/* Mobile nav */
.dt-nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--dt-border-bright);
  color: var(--dt-text);
  font-size: 1.2rem;
  cursor: pointer;
  padding: 8px 12px;
  border-radius: var(--dt-radius-sm);
  transition: all var(--dt-transition);
}

.dt-nav-toggle:hover {
  border-color: var(--dt-green);
  color: var(--dt-green);
}

@media (max-width: 720px) {
  .dt-nav-toggle { display: block; }
  .dt-nav-links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(5, 5, 8, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--dt-glass-border);
    padding: 12px 20px 16px;
    gap: 2px;
  }
  .dt-nav-links.open { display: flex; }
  .dt-nav-links a {
    width: 100%;
    padding: 14px 18px;
    font-size: 0.8rem;
  }
}

/* === GLASS CARDS === */
.dt-card {
  position: relative;
  background: var(--dt-glass);
  backdrop-filter: blur(16px) saturate(1.2);
  -webkit-backdrop-filter: blur(16px) saturate(1.2);
  border: 1px solid var(--dt-glass-border);
  border-radius: var(--dt-radius-lg);
  padding: 28px;
  transition: all 0.4s var(--dt-ease);
  overflow: hidden;
}

/* Subtle inner shine */
.dt-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.08), transparent);
}

.dt-card:hover {
  border-color: rgba(42, 127, 255, 0.2);
  box-shadow:
    0 8px 32px rgba(0, 0, 0, 0.3),
    0 0 0 1px rgba(42, 127, 255, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 0.04);
  transform: translateY(-2px);
}

/* Glowing variant */
.dt-card-glow {
  border-color: rgba(42, 255, 128, 0.15);
  box-shadow: 0 0 40px var(--dt-green-dim);
}

/* Gradient border card */
.dt-card-gradient {
  background: var(--dt-surface-solid);
  border: none;
  position: relative;
  z-index: 0;
}

.dt-card-gradient::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--dt-radius-lg);
  padding: 1px;
  background: linear-gradient(135deg, var(--dt-green), var(--dt-blue), var(--dt-cyan));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  z-index: -1;
  opacity: 0.4;
  transition: opacity 0.4s var(--dt-ease);
}

.dt-card-gradient:hover::after {
  opacity: 0.8;
}

/* === BUTTONS === */
.dt-btn {
  font-family: var(--dt-font-display);
  font-weight: 700;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 14px 28px;
  border: none;
  border-radius: var(--dt-radius);
  cursor: pointer;
  transition: all 0.35s var(--dt-ease);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  position: relative;
  overflow: hidden;
  text-decoration: none;
}

/* Shine sweep on hover */
.dt-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.15), transparent);
  transition: left 0.5s var(--dt-ease);
}

.dt-btn:hover::before { left: 100%; }

.dt-btn-primary {
  background: linear-gradient(135deg, var(--dt-green), var(--dt-green-mid));
  color: #000;
  box-shadow: 0 4px 20px var(--dt-green-dim);
}

.dt-btn-primary:hover {
  box-shadow: 0 6px 32px var(--dt-green-glow);
  transform: translateY(-2px);
}

.dt-btn-secondary {
  background: linear-gradient(135deg, var(--dt-blue), #1a5fcc);
  color: #fff;
  box-shadow: 0 4px 20px var(--dt-blue-dim);
}

.dt-btn-secondary:hover {
  box-shadow: 0 6px 32px var(--dt-blue-glow);
  transform: translateY(-2px);
}

.dt-btn-outline {
  background: transparent;
  color: var(--dt-text);
  border: 1px solid var(--dt-border-bright);
}

.dt-btn-outline:hover {
  border-color: var(--dt-green);
  color: var(--dt-green);
  background: var(--dt-green-dim);
  box-shadow: 0 0 20px var(--dt-green-dim);
}

.dt-btn-sm {
  padding: 10px 18px;
  font-size: 0.7rem;
}

.dt-btn-lg {
  padding: 18px 40px;
  font-size: 0.85rem;
  border-radius: var(--dt-radius-lg);
}

/* === INPUTS === */
.dt-input {
  font-family: var(--dt-font-body);
  font-size: 0.9rem;
  font-weight: 400;
  padding: 14px 18px;
  background: rgba(10, 11, 16, 0.6);
  color: var(--dt-text);
  border: 1px solid var(--dt-border-bright);
  border-radius: var(--dt-radius);
  outline: none;
  transition: all var(--dt-transition);
  width: 100%;
  backdrop-filter: blur(8px);
}

.dt-input:focus {
  border-color: var(--dt-blue);
  box-shadow: 0 0 0 3px var(--dt-blue-dim), 0 0 20px var(--dt-blue-dim);
  background: rgba(10, 11, 16, 0.8);
}

.dt-input::placeholder { color: var(--dt-text-muted); }

/* === BADGES === */
.dt-badge {
  font-family: var(--dt-font-display);
  font-weight: 700;
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 5px 12px;
  border-radius: 6px;
  display: inline-block;
}

.dt-badge-green {
  background: var(--dt-green-dim);
  color: var(--dt-green);
  border: 1px solid rgba(42, 255, 128, 0.2);
}

.dt-badge-blue {
  background: var(--dt-blue-dim);
  color: var(--dt-blue);
  border: 1px solid rgba(42, 127, 255, 0.2);
}

.dt-badge-red {
  background: rgba(255, 59, 59, 0.12);
  color: var(--dt-red);
  border: 1px solid rgba(255, 59, 59, 0.2);
}

/* === FOOTER === */
.dt-footer {
  border-top: 1px solid var(--dt-glass-border);
  padding: 28px 0;
  text-align: center;
  color: var(--dt-text-muted);
  font-size: 0.8rem;
  font-family: var(--dt-font-display);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.dt-footer a { color: var(--dt-text-dim); }
.dt-footer a:hover { color: var(--dt-green); }

/* === SECTION LABEL (e.g. "01 / FEATURES") === */
.dt-section-label {
  font-family: var(--dt-font-display);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--dt-text-muted);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.dt-section-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--dt-border-bright), transparent);
}

/* === DIVIDER === */
.dt-divider {
  border: none;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--dt-border-bright), transparent);
  margin: 40px 0;
}

/* === UTILITY === */
.dt-text-green { color: var(--dt-green); }
.dt-text-blue { color: var(--dt-blue); }
.dt-text-cyan { color: var(--dt-cyan); }
.dt-text-dim { color: var(--dt-text-dim); }
.dt-text-bright { color: var(--dt-text-bright); }
.dt-text-center { text-align: center; }
.dt-mt-1 { margin-top: 10px; }
.dt-mt-2 { margin-top: 20px; }
.dt-mt-3 { margin-top: 32px; }
.dt-mt-4 { margin-top: 48px; }
.dt-mb-1 { margin-bottom: 10px; }
.dt-mb-2 { margin-bottom: 20px; }
.dt-mb-3 { margin-bottom: 32px; }
.dt-flex { display: flex; }
.dt-flex-col { flex-direction: column; }
.dt-gap-1 { gap: 10px; }
.dt-gap-2 { gap: 16px; }
.dt-gap-3 { gap: 24px; }
.dt-wrap { flex-wrap: wrap; }
.dt-items-center { align-items: center; }
.dt-justify-center { justify-content: center; }

/* === ANIMATIONS === */
@keyframes dt-fade-up {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes dt-fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes dt-glow-pulse {
  0%, 100% { box-shadow: 0 0 15px var(--dt-green-dim); }
  50% { box-shadow: 0 0 35px var(--dt-green-glow); }
}

@keyframes dt-scan {
  0% { transform: translateY(-100%); }
  100% { transform: translateY(100vh); }
}

.dt-animate {
  opacity: 0;
  animation: dt-fade-up 0.7s var(--dt-ease) forwards;
}

.dt-delay-1 { animation-delay: 0.1s; }
.dt-delay-2 { animation-delay: 0.2s; }
.dt-delay-3 { animation-delay: 0.35s; }
.dt-delay-4 { animation-delay: 0.5s; }
.dt-delay-5 { animation-delay: 0.65s; }