/* ============================================================
   CustomA2DP — landing page
   tokens → base → components → sections → responsive
   ============================================================ */

/* ---------- tokens ---------- */
:root {
  --bg:          #070A12;
  --surface:     rgba(255, 255, 255, .032);
  --surface-2:   rgba(255, 255, 255, .055);
  --border:      rgba(255, 255, 255, .09);
  --border-str:  rgba(255, 255, 255, .16);

  --text:        #E9EEF8;
  --text-soft:   #B3BFD4;
  --muted:       #8494AE;

  --a1:          #22D3EE;
  --a2:          #3B82F6;
  --a3:          #8B5CF6;
  --grad:        linear-gradient(100deg, var(--a1), var(--a2) 48%, var(--a3));

  --ok:          #34D399;
  --bad:         #FB7185;
  --warn:        #FBBF24;

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

  --shell:       1180px;
  --pad:         clamp(18px, 4vw, 32px);

  --shadow-glow: 0 0 0 1px rgba(59, 130, 246, .22), 0 26px 70px -26px rgba(59, 130, 246, .55);

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI Variable Display", "Segoe UI",
          Inter, Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --mono: ui-monospace, "Cascadia Mono", "Cascadia Code", Consolas, "SF Mono", Menlo, monospace;

  --ease: cubic-bezier(.22, .61, .36, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 92px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; }

h1, h2, h3 {
  margin: 0;
  line-height: 1.14;
  letter-spacing: -.022em;
  font-weight: 700;
}

p { margin: 0; }
ul, ol, dl, dd { margin: 0; padding: 0; }
li { list-style: none; }
a { color: inherit; text-decoration: none; }

code, .mono {
  font-family: var(--mono);
  font-size: .88em;
  font-variant-ligatures: none;
}

code {
  padding: .12em .42em;
  border-radius: 6px;
  background: rgba(59, 130, 246, .13);
  border: 1px solid rgba(59, 130, 246, .2);
  color: #C7DBFE;
}

.mono--wrap { word-break: break-all; }

:focus-visible {
  outline: 2px solid var(--a1);
  outline-offset: 3px;
  border-radius: 6px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 12px;
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  background: var(--a2);
  color: #fff;
  font-weight: 600;
}
.skip-link:focus { left: 12px; }

.shell {
  width: min(100% - var(--pad) * 2, var(--shell));
  margin-inline: auto;
}
.shell--narrow { width: min(100% - var(--pad) * 2, 830px); }

/* ---------- background ---------- */
.bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

.bg__mesh {
  position: absolute;
  inset: -25%;
  background:
    radial-gradient(46rem 30rem at 18% 8%,  rgba(34, 211, 238, .16), transparent 62%),
    radial-gradient(42rem 30rem at 84% 2%,  rgba(139, 92, 246, .17), transparent 62%),
    radial-gradient(52rem 34rem at 62% 92%, rgba(59, 130, 246, .14), transparent 64%);
  filter: blur(12px);
  animation: drift 26s var(--ease) infinite alternate;
}

.bg__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .028) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .028) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(70% 55% at 50% 32%, #000 20%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 55% at 50% 32%, #000 20%, transparent 78%);
}

.bg__noise {
  position: absolute;
  inset: 0;
  opacity: .45;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.4'/%3E%3C/svg%3E");
}

@keyframes drift {
  from { transform: translate3d(-2%, -1%, 0) scale(1); }
  to   { transform: translate3d(2%, 2%, 0) scale(1.08); }
}

/* ---------- header ---------- */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid transparent;
  transition: background .3s var(--ease), border-color .3s var(--ease);
}

.header.is-stuck {
  background: rgba(7, 10, 18, .78);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom-color: var(--border);
}

.header__inner {
  display: flex;
  align-items: center;
  gap: 20px;
  height: 74px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  flex-shrink: 0;
}

.brand__mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  filter: drop-shadow(0 6px 16px rgba(59, 130, 246, .45));
}

.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-weight: 700; letter-spacing: -.02em; font-size: 1.02rem; }
.brand__ver { font-family: var(--mono); font-size: .69rem; color: var(--muted); }

.nav {
  display: flex;
  gap: 4px;
  margin-inline: auto;
}

.nav__link {
  padding: 8px 13px;
  border-radius: 9px;
  font-size: .93rem;
  color: var(--text-soft);
  transition: color .2s, background .2s;
}
.nav__link:hover { color: var(--text); background: var(--surface); }

.header__cta { display: flex; gap: 9px; flex-shrink: 0; }

.burger {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  margin-left: auto;
  border: 1px solid var(--border);
  border-radius: 11px;
  background: var(--surface);
  cursor: pointer;
}
.burger span {
  display: block;
  width: 17px;
  height: 1.8px;
  margin: 3.6px auto;
  border-radius: 2px;
  background: var(--text);
  transition: transform .25s var(--ease), opacity .2s;
}
.burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(5.4px) rotate(45deg); }
.burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-5.4px) rotate(-45deg); }

.mobile-nav {
  display: none;
  flex-direction: column;
  gap: 3px;
  padding: 10px var(--pad) 22px;
  background: rgba(7, 10, 18, .97);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}
.mobile-nav a {
  padding: 12px 14px;
  border-radius: 11px;
  color: var(--text-soft);
  font-weight: 500;
}
.mobile-nav a:hover { background: var(--surface); color: var(--text); }
.mobile-nav .btn { margin-top: 8px; justify-content: center; color: #04070F; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 12px 20px;
  border: 1px solid transparent;
  border-radius: 12px;
  font-size: .95rem;
  font-weight: 600;
  letter-spacing: -.01em;
  cursor: pointer;
  white-space: nowrap;
  transition: transform .18s var(--ease), box-shadow .25s var(--ease),
              background .25s var(--ease), border-color .25s var(--ease), color .2s;
}

.btn__icon {
  width: 17px;
  height: 17px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.btn--primary {
  color: #04070F;
  background: var(--grad);
  box-shadow: 0 10px 30px -12px rgba(59, 130, 246, .8);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 18px 44px -14px rgba(59, 130, 246, .95); }

.btn--outline {
  color: var(--text);
  border-color: var(--border-str);
  background: var(--surface);
}
.btn--outline:hover {
  transform: translateY(-2px);
  border-color: rgba(34, 211, 238, .55);
  background: var(--surface-2);
}

.btn--ghost { color: var(--text-soft); }
.btn--ghost:hover { color: var(--text); background: var(--surface); }

.btn--sm { padding: 9px 15px; font-size: .89rem; border-radius: 10px; }
.btn--lg { padding: 15px 27px; font-size: 1.02rem; border-radius: 14px; }