/* Базовые переменные темы */
:root {
  --bg-primary: #0a0a0a;
  --bg-secondary: #141414;
  --glass-bg: rgba(255,255,255,.03);
  --glass-border: rgba(255,255,255,.08);
  --bg-hover: rgba(255,255,255,.05);

  --text-primary: #fff;
  --text-secondary: rgba(255,255,255,.75);
  --text-tertiary: rgba(255,255,255,.55);

  --accent-primary: #7c3aed;
  --accent-secondary: #ec4899;
  --accent-gradient: linear-gradient(135deg, #7c3aed, #ec4899);

  --shadow-color: rgba(124, 58, 237, .18);
  --header-h: 72px;
  --footer-h: 60px;

  /* Fluid type scale */
  --fs-0: clamp(15px, 0.9vw + 12px, 18px);     /* base */
  --fs-1: clamp(1rem, 1.2vw + .8rem, 1.25rem);  /* body lg / buttons */
  --fs-2: clamp(1.25rem, 1.6vw + .9rem, 1.6rem);/* h3 */
  --fs-3: clamp(1.6rem, 2.2vw + 1rem, 2.2rem);  /* h2 */
  --fs-4: clamp(2rem, 3vw + 1.2rem, 3rem);      /* h1 */
}

.light {
  --bg-primary:#fff; --bg-secondary:#f5f5f5;
  --glass-bg: rgba(245,245,245,.8);
  --glass-border: rgba(0,0,0,.06);
  --bg-hover: rgba(0,0,0,.06);
  --text-primary:#0a0a0a;
  --text-secondary: rgba(0,0,0,.75);
  --text-tertiary: rgba(0,0,0,.55);
  --shadow-color: rgba(124, 58, 237, .15);
}

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

html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  margin: 0;
  font-size: var(--fs-0);
  line-height: 1.55;
  min-height: 100dvh;
  display: grid;
  grid-template-rows: var(--header-h) 1fr var(--footer-h);
}

/* Сервисные элементы */
.skip-link {
  position:absolute; left:-9999px; top:auto; width:1px; height:1px; overflow:hidden;
}
.skip-link:focus {
  position:fixed; left:1rem; top:1rem; width:auto; height:auto;
  background: var(--glass-bg);
  border:1px solid var(--glass-border);
  padding:.5rem .75rem; border-radius:.5rem; z-index:10000;
}

/* Canvas на заднем плане */
#particle-canvas {
  position: fixed; inset: 0;
  width: 100vw; height: 100vh;
  z-index: -1; opacity: .85;
  pointer-events: none;
}

/* Header */
header {
  position: sticky; top: 0; z-index: 1000;
  height: var(--header-h);
  display:flex; align-items:center;
  background: var(--glass-bg);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom:1px solid var(--glass-border);
  padding: 0 1.25rem;
}
.header-content {
  max-width: 1200px; margin-inline:auto;
  display:flex; align-items:center; justify-content:space-between;
  width:100%;
}
.logo {
  font-weight: 800; letter-spacing:.2px;
  background: var(--accent-gradient);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
  font-size: var(--fs-2);
}
.nav-buttons { display:flex; gap:.75rem; }
.nav-button {
  width:44px; height:44px; border-radius:12px;
  background:var(--glass-bg);
  border:1px solid var(--glass-border);
  display:grid; place-items:center;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
  color: var(--text-primary);
}
.nav-button:hover {
  transform: translateY(-2px);
  border-color: var(--accent-primary);
  box-shadow:0 10px 20px var(--shadow-color);
}
.nav-button svg { width:24px; height:24px; }

/* Main */
.main {
  text-align:center;
  padding: 2rem 1rem;
  display:grid; place-items:center;
}
h1 { font-size: var(--fs-4); font-weight: 800; line-height: 1.15;
     background: var(--accent-gradient);
     -webkit-background-clip: text; background-clip: text;
     -webkit-text-fill-color: transparent; }

.yin {
  width: clamp(120px, 22vw, 200px);
  margin: 1rem auto 1.25rem;
  filter: drop-shadow(0 0 30px rgba(124,58,237,.5));
}
@media (prefers-reduced-motion: no-preference) {
  .yin { animation: spin 22s linear infinite; }
  @keyframes spin { to { transform: rotate(360deg); } }
}

.cta-container {
  display:grid;
  grid-template-columns: repeat(5, minmax(0,1fr));
  gap: .8rem; max-width: 720px; width: 100%;
}
.cta {
  padding: .9rem 1.2rem;
  font-size: var(--fs-1);
  font-weight: 600;
  color: var(--text-primary);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  text-decoration: none; text-align:center;
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
  backdrop-filter: blur(10px);
}
.cta:hover {
  transform: translateY(-2px);
  border-color: var(--accent-primary);
  box-shadow: 0 12px 24px var(--shadow-color);
}

/* Footer */
.footer {
  position: sticky; bottom: 0; z-index: 1000;
  background: var(--glass-bg);
  border-top:1px solid var(--glass-border);
  display:grid; place-items:center;
}
.footer-content {
  max-width: 1200px; margin-inline:auto;
  padding: .75rem 1rem;
  display:grid; gap:.4rem; place-items:center;
}
.footer-links {
  display:flex; gap:1.25rem; flex-wrap:wrap; justify-content:center;
}
.footer-links a {
  color: var(--text-secondary);
  font-size: .95rem; text-decoration:none; position:relative;
}
.footer-links a:hover { color: var(--accent-primary); }

/* Cookie banner */
.cookie {
  position: fixed; left:50%; transform: translateX(-50%);
  bottom: calc(var(--footer-h) + 8px);
  background: rgba(0,0,0,.7); color:#fff;
  border-radius: 12px; padding: .75rem 1rem; display:flex; gap: .75rem;
  align-items:center; z-index: 1100; max-width: 640px;
}
.light .cookie { background: rgba(255,255,255,.92); color:#000; }
.cookie button {
  padding: .7rem 1.2rem; border-radius: 12px; border:0; font-weight:700;
  background: var(--accent-gradient); color:#fff; cursor:pointer;
}

/* Модалка формы */
.feedback-form-container {
  position: fixed; inset: 0; display: grid; place-items: center; z-index: 1200;
  background: rgba(0,0,0,.6);
  backdrop-filter: blur(10px);
}
.feedback-form {
  background: var(--bg-secondary);
  border:1px solid var(--glass-border);
  border-radius: 18px; padding: 1.5rem; width:min(92vw, 480px);
  box-shadow: 0 22px 48px rgba(0,0,0,.45); position: relative;
}
.feedback-form h2 {
  font-size: var(--fs-3);
  margin-bottom: 1rem;
  background: var(--accent-gradient);
  -webkit-background-clip:text; background-clip:text;
  -webkit-text-fill-color: transparent;
}
.feedback-form input,
.feedback-form textarea {
  width:100%; margin-bottom:.8rem; padding: .9rem 1rem;
  border-radius: 12px; border:1px solid var(--glass-border);
  background: var(--glass-bg); color: var(--text-primary);
  font-size: 1rem;
}
.feedback-form input:focus,
.feedback-form textarea:focus {
  outline: none; border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px var(--shadow-color);
}
.feedback-form textarea { min-height: 120px; resize: vertical; }
.hp { display:none !important; }

.close-button {
  position:absolute; right:.75rem; top:.75rem; width:40px; height:40px;
  border-radius:50%; border:0; background:transparent; color:var(--text-secondary);
  font-size: 1.8rem; cursor: pointer;
}
.close-button:hover { background: var(--bg-hover); color: var(--accent-primary); }

.form-message {
  margin-top:.5rem; font-size:.95rem; padding:.6rem .75rem;
  border-radius: 8px; opacity:1; transform: none;
}
.form-message.success { background: rgba(34,197,94,.1); color:#22c55e; border:1px solid rgba(34,197,94,.25); }
.form-message.error   { background: rgba(239,68,68,.1); color:#ef4444; border:1px solid rgba(239,68,68,.25); }

/* Мобильная адаптация */
@media (max-width: 768px) {
  :root { --header-h: 60px; }
  .cta-container { grid-template-columns: 1fr; }
}

/* Доступность и анимации */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}