/* ==========================================================================
   Didi Studio Group — one-page site
   Fonts: Space Grotesk (display) + Inter (body)
   Palette: deep graphite base, ink text, electric indigo + signal cyan accents
   ========================================================================== */

:root{
  --bg: #0a0b0d;
  --bg-soft: #101215;
  --surface: #14161b;
  --surface-2: #191c22;
  --border: rgba(255,255,255,0.08);
  --border-soft: rgba(255,255,255,0.05);

  --text: #ecedef;
  --text-dim: #9ca0aa;
  --text-faint: #6b6f79;

  --accent: #5b6cff;
  --accent-2: #43e6c4;
  --accent-soft: rgba(91,108,255,0.14);

  --font-display: 'Space Grotesk', 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;

  --ease: cubic-bezier(.16,.8,.24,1);
}

*{ margin:0; padding:0; box-sizing:border-box; }
html{ scroll-behavior: smooth; }
body{
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a{ color: inherit; text-decoration: none; }
ul{ list-style: none; }
img{ max-width: 100%; display:block; }
h1,h2,h3{ font-family: var(--font-display); letter-spacing: -0.02em; font-weight: 600; line-height: 1.08; }
.eyebrow{ font-size: 0.8rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--accent-2); font-weight: 500; margin-bottom: 14px; }

.noise{
  position: fixed; inset: 0; pointer-events: none; z-index: 2; opacity: 0.035;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mix-blend-mode: overlay;
}
.cursor-glow{
  position: fixed; width: 420px; height: 420px; border-radius: 50%;
  background: radial-gradient(circle, rgba(91,108,255,0.10), transparent 70%);
  pointer-events: none; z-index: 1; transform: translate(-50%,-50%);
  transition: opacity .3s ease; opacity: 0;
}

.nav{
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  backdrop-filter: blur(14px) saturate(140%);
  background: rgba(10,11,13,0.55);
  border-bottom: 1px solid var(--border-soft);
  transition: background .3s var(--ease), border-color .3s var(--ease);
}
.nav-inner{ max-width: 1200px; margin: 0 auto; padding: 18px 32px; display: flex; align-items: center; justify-content: space-between; }
.brand{ display: flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 600; font-size: 1.02rem; }
.brand-mark{
  display: inline-flex; align-items: center; justify-content: center; width: 32px; height: 32px; border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #060608; font-size: 0.78rem; font-weight: 700; letter-spacing: -0.02em;
}
.nav-links{ display: flex; align-items: center; gap: 32px; font-size: 0.92rem; color: var(--text-dim); }
.nav-links a{ transition: color .25s var(--ease); position: relative; }
.nav-links a:hover{ color: var(--text); }
.nav-cta{ padding: 9px 18px; border-radius: 999px; background: var(--text); color: var(--bg) !important; font-weight: 500; }
.nav-cta:hover{ background: var(--accent-2); }
.nav-toggle{ display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; }
.nav-toggle span{ width: 22px; height: 2px; background: var(--text); }

.hero{ position: relative; min-height: 100vh; display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 140px 24px 80px; overflow: hidden; }
.hero-bg{ position: absolute; inset: 0; z-index: 0; }
.mesh{ position: absolute; border-radius: 50%; filter: blur(90px); opacity: 0.55; animation: drift 18s ease-in-out infinite alternate; }
.mesh-1{ width: 560px; height: 560px; background: radial-gradient(circle, var(--accent), transparent 70%); top: -140px; left: -100px; }
.mesh-2{ width: 480px; height: 480px; background: radial-gradient(circle, var(--accent-2), transparent 70%); bottom: -160px; right: -80px; animation-delay: -6s; }
@keyframes drift{ from{ transform: translate(0,0) scale(1); } to{ transform: translate(40px,-30px) scale(1.12); } }
.grid-overlay{
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, black 20%, transparent 80%);
}
.hero-content{ position: relative; z-index: 2; max-width: 880px; text-align: center; }
.hero-title{ font-size: clamp(2.6rem, 6.4vw, 4.6rem); margin-bottom: 26px; }
.hero-title .line{ display: block; }
.hero-sub{ font-size: 1.1rem; color: var(--text-dim); max-width: 560px; margin: 0 auto 40px; }
.hero-actions{ display: flex; gap: 16px; justify-content: center; margin-bottom: 64px; flex-wrap: wrap; }
.btn{ position: relative; display: inline-flex; align-items: center; justify-content: center; padding: 14px 28px; border-radius: 999px; font-weight: 500; font-size: 0.95rem; overflow: hidden; transition: transform .35s var(--ease), background .3s var(--ease), border-color .3s var(--ease); }
.btn span{ position: relative; z-index: 2; }
.btn-primary{ background: var(--text); color: var(--bg); }
.btn-primary:hover{ background: var(--accent-2); transform: translateY(-2px); }
.btn-ghost{ border: 1px solid var(--border); color: var(--text); background: transparent; }
.btn-ghost:hover{ border-color: var(--accent); background: var(--accent-soft); transform: translateY(-2px); }
.btn-lg{ padding: 18px 34px; font-size: 1rem; }
.hero-stats{ display: flex; gap: 48px; justify-content: center; flex-wrap: wrap; border-top: 1px solid var(--border-soft); padding-top: 32px; }
.stat{ display: flex; flex-direction: column; align-items: center; gap: 6px; max-width: 160px; }
.stat-num, .stat-suffix{ font-family: var(--font-display); font-size: 1.9rem; font-weight: 600; color: var(--text); }
.stat-label{ font-size: 0.8rem; color: var(--text-faint); text-align: center; }
.scroll-cue{ position: absolute; bottom: 32px; display: flex; flex-direction: column; align-items: center; gap: 8px; color: var(--text-faint); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; }
.scroll-cue span{ width: 1px; height: 30px; background: linear-gradient(to bottom, var(--accent-2), transparent); animation: scrollLine 1.8s ease-in-out infinite; }
@keyframes scrollLine{ 0%{ transform: scaleY(0.3); opacity: 0.4; } 50%{ transform: scaleY(1); opacity: 1; } 100%{ transform: scaleY(0.3); opacity: 0.4; } }

.trust-strip{ padding: 48px 24px; text-align: center; border-top: 1px solid var(--border-soft); border-bottom: 1px solid var(--border-soft); }
.trust-strip p{ color: var(--text-faint); font-size: 0.85rem; margin-bottom: 24px; }
.trust-row{ display: flex; gap: 40px; justify-content: center; flex-wrap: wrap; font-family: var(--font-display); font-size: 1rem; color: var(--text-dim); }

.section-head{ max-width: 720px; margin: 0 auto 56px; padding: 0 24px; text-align: center; }
.section-head h2{ font-size: clamp(1.8rem, 3.6vw, 2.6rem); }
section{ padding: 120px 24px; position: relative; }

.bento{ max-width: 1100px; margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card{ background: linear-gradient(160deg, var(--surface), var(--bg-soft)); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 32px; transition: transform .4s var(--ease), border-color .4s var(--ease), background .4s var(--ease); }
.card:hover{ transform: translateY(-6px); border-color: rgba(91,108,255,0.4); }
.card-lg{ grid-column: span 2; grid-row: span 2; }
.card-wide{ grid-column: span 2; }
.card-icon{ width: 44px; height: 44px; border-radius: 12px; background: var(--accent-soft); color: var(--accent-2); display: flex; align-items: center; justify-content: center; margin-bottom: 20px; }
.card-icon svg{ width: 22px; height: 22px; }
.card h3{ font-size: 1.2rem; margin-bottom: 10px; }
.card p{ color: var(--text-dim); font-size: 0.95rem; }
.card-list{ margin-top: 18px; display: grid; gap: 8px; }
.card-list li{ font-size: 0.88rem; color: var(--text-dim); padding-left: 18px; position: relative; }
.card-list li::before{ content: ''; position: absolute; left: 0; top: 8px; width: 6px; height: 6px; border-radius: 50%; background: var(--accent-2); }

.steps{ max-width: 1100px; margin: 0 auto; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.step{ padding: 28px 24px; border-top: 1px solid var(--border); position: relative; }
.step-num{ display: block; font-family: var(--font-display); font-size: 0.85rem; color: var(--accent-2); margin-bottom: 14px; }
.step h3{ font-size: 1.1rem; margin-bottom: 10px; }
.step p{ color: var(--text-dim); font-size: 0.9rem; }

.who-grid{ max-width: 1100px; margin: 0 auto; display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.who-card{ padding: 28px 22px; border-radius: var(--radius-md); background: var(--surface); border: 1px solid var(--border); transition: transform .35s var(--ease), border-color .35s var(--ease); }
.who-card:hover{ transform: translateY(-4px); border-color: rgba(67,230,196,0.35); }
.who-card h3{ font-size: 1.05rem; margin-bottom: 8px; }
.who-card p{ color: var(--text-dim); font-size: 0.88rem; }

.cta{ text-align: center; background: radial-gradient(ellipse at 50% 0%, rgba(91,108,255,0.14), transparent 60%); }
.cta-inner{ max-width: 640px; margin: 0 auto; }
.cta h2{ font-size: clamp(2rem, 4vw, 3rem); margin-bottom: 16px; }
.cta-sub{ color: var(--text-dim); margin-bottom: 40px; }

.footer{ border-top: 1px solid var(--border-soft); padding: 48px 24px; }
.footer-inner{ max-width: 1200px; margin: 0 auto; display: flex; flex-wrap: wrap; gap: 20px; align-items: center; justify-content: space-between; }
.footer-brand{ display: flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 600; }
.footer-legal{ font-size: 0.8rem; color: var(--text-faint); text-align: center; flex: 1; min-width: 260px; }
.footer-links{ display: flex; gap: 24px; font-size: 0.88rem; color: var(--text-dim); }
.footer-links a:hover{ color: var(--text); }

.reveal{ opacity: 0; transform: translateY(24px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.is-visible{ opacity: 1; transform: translateY(0); }
@supports (animation-timeline: view()) {
  .reveal{ opacity: 1; transform: none; animation: fadeUp linear both; animation-timeline: view(); animation-range: entry 0% cover 30%; }
}
@keyframes fadeUp{ from{ opacity: 0; transform: translateY(28px); } to{ opacity: 1; transform: translateY(0); } }

@media (max-width: 900px){
  .bento{ grid-template-columns: repeat(2, 1fr); }
  .card-lg{ grid-column: span 2; grid-row: span 1; }
  .steps{ grid-template-columns: repeat(2, 1fr); }
  .who-grid{ grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px){
  .nav-links{ display: none; }
  .nav-toggle{ display: flex; }
  .bento{ grid-template-columns: 1fr; }
  .card-lg, .card-wide{ grid-column: span 1; }
  .steps{ grid-template-columns: 1fr; }
  .who-grid{ grid-template-columns: 1fr; }
  .hero-stats{ gap: 28px; }
  section{ padding: 88px 20px; }
  .cursor-glow{ display: none; }
}