/* SingularOS — singularos.net
   Static, build-free. Dark, governance-forward, AI-native. */
:root {
  --bg:        #0a0e14;
  --bg-alt:    #0e141f;
  --surface:   #131b29;
  --surface-2: #182030;
  --border:    #233047;
  --text:      #e8edf4;
  --muted:     #9fb0c8;
  --faint:     #6b7c96;
  --accent:    #5eead4;   /* teal */
  --accent-2:  #7c9cff;   /* indigo */
  --accent-ink:#04221c;
  --radius:    16px;
  --maxw:      1120px;
  --ease:      cubic-bezier(.22,.61,.36,1);
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
[lang="ua"] { --font: "Inter", -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.container--narrow { max-width: 760px; }

a { color: inherit; text-decoration: none; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: .5rem; font-weight: 600; font-size: .95rem; line-height: 1;
  padding: .85rem 1.4rem; border-radius: 999px; border: 1px solid transparent;
  cursor: pointer; transition: transform .18s var(--ease), box-shadow .18s var(--ease), background .18s, border-color .18s;
  white-space: nowrap;
}
.btn--sm { padding: .6rem 1rem; font-size: .85rem; }
.btn--lg { padding: 1rem 1.8rem; font-size: 1.05rem; }
.btn--primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: var(--accent-ink); box-shadow: 0 8px 30px -10px rgba(94,234,212,.5);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 14px 40px -10px rgba(94,234,212,.6); }
.btn--ghost { border-color: var(--border); color: var(--text); background: transparent; }
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }

/* ---------- nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(12px);
  background: rgba(10,14,20,.72);
  border-bottom: 1px solid var(--border);
}
.nav__inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.nav__brand { display: flex; align-items: center; gap: .6rem; font-weight: 700; font-size: 1.15rem; letter-spacing: -.01em; }
.nav__mark {
  width: 18px; height: 18px; border-radius: 6px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 18px -2px rgba(94,234,212,.6);
}
.nav__links { display: flex; gap: 2rem; }
.nav__links a { color: var(--muted); font-size: .95rem; transition: color .15s; }
.nav__links a:hover { color: var(--text); }
.nav__actions { display: flex; align-items: center; gap: .85rem; }
.lang-toggle {
  background: transparent; border: 1px solid var(--border); color: var(--muted);
  font-family: inherit; font-size: .82rem; font-weight: 600; padding: .5rem .8rem;
  border-radius: 999px; cursor: pointer; transition: all .15s;
}
.lang-toggle:hover { color: var(--text); border-color: var(--accent); }

/* ---------- eyebrow / headings ---------- */
.eyebrow {
  text-transform: uppercase; letter-spacing: .14em; font-size: .78rem; font-weight: 700;
  color: var(--accent); margin-bottom: 1rem;
}
.section__title { font-size: clamp(1.8rem, 3.4vw, 2.6rem); line-height: 1.15; letter-spacing: -.02em; max-width: 22ch; }
.section__title--center { margin-left: auto; margin-right: auto; }
.section__lead { color: var(--muted); font-size: 1.15rem; margin-top: 1rem; max-width: 62ch; }
.center { text-align: center; }
.center .eyebrow, .center .section__lead, .center .subline { margin-left: auto; margin-right: auto; }
.subline { color: var(--faint); font-size: 1.05rem; margin-top: 1rem; max-width: 56ch; font-style: italic; }
.closer { margin-top: 2rem; color: var(--text); font-size: 1.2rem; font-weight: 500; max-width: 60ch; }

/* checklists (cost / needed) */
.checklist { list-style: none; margin-top: 2rem; display: grid; gap: .9rem; max-width: 60ch; }
.checklist li { position: relative; padding-left: 2rem; color: var(--muted); font-size: 1.05rem; }
.checklist li::before {
  content: ""; position: absolute; left: 0; top: .55em; width: 9px; height: 9px; border-radius: 2px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}
.checklist--check li::before {
  content: "✓"; background: none; color: var(--accent); font-weight: 800; top: 0; width: auto; height: auto; font-size: 1.1rem;
}
.card__dot { display: block; width: 10px; height: 10px; border-radius: 50%; margin-bottom: 1rem; background: linear-gradient(135deg, var(--accent), var(--accent-2)); }

/* status badge */
.badge {
  display: inline-flex; align-items: center; gap: .5rem; font-size: .82rem; font-weight: 600;
  color: var(--accent); padding: .4rem .8rem; border: 1px solid var(--border); border-radius: 999px;
  background: rgba(94,234,212,.06);
}

/* ---------- hero ---------- */
.hero { position: relative; overflow: hidden; padding: clamp(4rem, 11vw, 9rem) 0 clamp(3.5rem, 8vw, 7rem); }
.hero__glow {
  position: absolute; inset: -30% 0 auto 0; height: 700px; pointer-events: none;
  background:
    radial-gradient(60% 60% at 25% 20%, rgba(124,156,255,.22), transparent 70%),
    radial-gradient(50% 50% at 80% 10%, rgba(94,234,212,.18), transparent 70%);
  filter: blur(8px);
}
.hero__inner { position: relative; }
.hero__title {
  font-size: clamp(2.4rem, 6.2vw, 4.4rem); line-height: 1.04; letter-spacing: -.03em;
  max-width: 17ch; margin-bottom: 1.4rem;
  background: linear-gradient(180deg, #fff, #c5d3e8);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero__sub { font-size: clamp(1.05rem, 1.8vw, 1.3rem); color: var(--muted); max-width: 60ch; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: 2.2rem; }
.hero__note { margin-top: 2rem; color: var(--faint); font-size: .9rem; display: flex; align-items: center; gap: .55rem; }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); flex: none; }

/* ---------- sections ---------- */
.section { padding: clamp(3.5rem, 8vw, 7rem) 0; }
.section--alt { background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.note-line { margin-top: 2rem; color: var(--faint); font-size: .92rem; display: flex; align-items: center; gap: .55rem; }

/* ---------- grids ---------- */
.grid { display: grid; gap: 1.25rem; margin-top: 2.6rem; }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

/* ---------- cards ---------- */
.card, .feature, .benefit {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 1.6rem; transition: transform .2s var(--ease), border-color .2s, background .2s;
}
.card:hover, .feature:hover, .benefit:hover { transform: translateY(-4px); border-color: var(--accent); background: var(--surface-2); }
.card h3, .feature h3, .benefit h3 { font-size: 1.12rem; margin-bottom: .55rem; letter-spacing: -.01em; }
.card p, .feature p, .benefit p { color: var(--muted); font-size: .98rem; }
.card--accent { position: relative; }
.card__num { display: block; font-size: .85rem; font-weight: 700; color: var(--accent); margin-bottom: .8rem; letter-spacing: .1em; }
.feature__icon {
  width: 44px; height: 44px; display: grid; place-items: center; border-radius: 12px;
  background: linear-gradient(135deg, rgba(94,234,212,.18), rgba(124,156,255,.18));
  color: var(--accent); font-size: 1.3rem; margin-bottom: 1rem; border: 1px solid var(--border);
}
.benefit { border-left: 3px solid var(--accent); }

/* ---------- flow (how it works) ---------- */
.flow { list-style: none; display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.25rem; margin-top: 2.6rem; counter-reset: step; }
.flow__step { position: relative; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.6rem; }
.flow__idx {
  display: grid; place-items: center; width: 38px; height: 38px; border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: var(--accent-ink);
  font-weight: 800; margin-bottom: 1rem;
}
.flow__step h3 { font-size: 1.1rem; margin-bottom: .5rem; }
.flow__step p { color: var(--muted); font-size: .96rem; }
.flow__step:not(:last-child)::after {
  content: "→"; position: absolute; right: -1.05rem; top: 2.4rem; color: var(--faint); font-size: 1.2rem; z-index: 2;
}

/* ---------- CTA ---------- */
.cta { position: relative; overflow: hidden; padding: clamp(4rem, 9vw, 7rem) 0; text-align: center; background: var(--bg-alt); border-top: 1px solid var(--border); }
.cta__glow { position: absolute; inset: auto 0 -40% 0; height: 500px; pointer-events: none;
  background: radial-gradient(50% 60% at 50% 100%, rgba(94,234,212,.2), transparent 70%); }
.cta__inner { position: relative; }
.cta__title { font-size: clamp(2rem, 4.4vw, 3rem); line-height: 1.1; letter-spacing: -.02em; margin: 0 auto 1.2rem; max-width: 20ch; }
.cta__body { color: var(--muted); font-size: 1.15rem; max-width: 52ch; margin: 0 auto 2.2rem; }

/* ---------- footer ---------- */
.footer { padding: 3rem 0; border-top: 1px solid var(--border); }
.footer__inner { display: flex; flex-direction: column; gap: .6rem; align-items: flex-start; }
.footer__top { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin-bottom: .4rem; }
.footer__brand { display: flex; align-items: center; gap: .6rem; font-weight: 700; }
.footer__tagline { color: var(--muted); max-width: 56ch; }
.footer__lang { color: var(--faint); font-size: .88rem; }
.footer__rights { color: var(--faint); font-size: .85rem; margin-top: .4rem; }

/* ---------- reveal animation ---------- */
.section, .hero__inner { }
[data-reveal] { opacity: 0; transform: translateY(18px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
[data-reveal].is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { [data-reveal] { opacity: 1; transform: none; transition: none; } html { scroll-behavior: auto; } }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .flow { grid-template-columns: repeat(2, 1fr); }
  .flow__step:not(:last-child)::after { display: none; }
  .nav__links { display: none; }
}
@media (max-width: 600px) {
  .grid--2, .grid--3, .grid--4, .flow { grid-template-columns: 1fr; }
  .container { padding: 0 18px; }
}