/* OpenNotch landing — palette lấy từ icon ứng dụng */
:root {
  --bg: #050507;
  --indigo-1: #23266b;
  --indigo-2: #15163a;
  --cyan: #38e1ff;
  --violet: #8b5cff;
  --pink: #ff4fb8;
  --text: #f4f4fa;
  --muted: #a6a8c4;
  --card: rgba(255, 255, 255, 0.045);
  --line: rgba(255, 255, 255, 0.1);
  --grad: linear-gradient(100deg, var(--cyan), var(--violet) 55%, var(--pink));
  --radius: 22px;
  --wrap: 1120px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0;
  background:
    radial-gradient(900px 520px at 50% -120px, rgba(139, 92, 255, 0.35), transparent 70%),
    radial-gradient(700px 480px at 0% 8%, rgba(56, 225, 255, 0.14), transparent 70%),
    radial-gradient(700px 480px at 100% 14%, rgba(255, 79, 184, 0.14), transparent 70%),
    var(--bg);
  background-repeat: no-repeat;
  color: var(--text);
  font: 400 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
img, video { max-width: 100%; display: block; }
a { color: inherit; }
h1, h2, h3 { margin: 0; line-height: 1.12; letter-spacing: -0.02em; }
p { margin: 0; }
em { font-style: normal; color: var(--text); font-weight: 600; }
.wrap { width: min(var(--wrap), 100% - 40px); margin-inline: auto; }
.grad { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }

:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; border-radius: 8px; }
.skip { position: absolute; left: -999px; top: 8px; z-index: 100; background: #fff; color: #000; padding: 8px 14px; border-radius: 8px; }
.skip:focus { left: 8px; }

/* ---------- Nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: saturate(160%) blur(18px);
  -webkit-backdrop-filter: saturate(160%) blur(18px);
  background: rgba(5, 5, 7, 0.62);
  border-bottom: 1px solid var(--line);
}
.nav-in { display: flex; align-items: center; gap: 24px; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; letter-spacing: -0.01em; text-decoration: none; }
.brand img { border-radius: 8px; }
.links { display: flex; gap: 6px; margin-left: auto; }
.links a { color: var(--muted); text-decoration: none; padding: 8px 12px; border-radius: 999px; font-size: 15px; transition: color .2s, background .2s; }
.links a:hover { color: var(--text); background: rgba(255, 255, 255, 0.07); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 48px; padding: 0 24px; border-radius: 999px;
  font: 600 16px/1 inherit; text-decoration: none; color: #07070c;
  background: var(--grad); border: 0; cursor: pointer;
  box-shadow: 0 10px 34px -8px rgba(139, 92, 255, 0.7);
  transition: transform .2s, box-shadow .2s, filter .2s;
}
.btn:hover { transform: translateY(-2px); filter: brightness(1.08); box-shadow: 0 16px 40px -8px rgba(255, 79, 184, 0.6); }
.btn svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.btn-sm { min-height: 40px; padding: 0 18px; font-size: 15px; }
.btn-ghost { color: var(--text); background: rgba(255, 255, 255, 0.07); box-shadow: inset 0 0 0 1px var(--line); }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.22); }

/* ---------- Hero ---------- */
.hero { padding: 56px 0 40px; text-align: center; }
.badge {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 7px 16px; border-radius: 999px; font-size: 14px; color: var(--muted);
  background: var(--card); border: 1px solid var(--line);
}
.badge .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 12px var(--cyan); }
.hero h1 { margin-top: 26px; font-size: clamp(44px, 8vw, 88px); font-weight: 800; letter-spacing: -0.035em; line-height: 1.02; }
.lead { margin: 26px auto 0; max-width: 680px; font-size: clamp(17px, 2.2vw, 20px); color: var(--muted); }
.cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; margin-top: 34px; }

/* ---------- Sections ---------- */
.sec { padding: 96px 0; }
.head { text-align: center; margin-bottom: 52px; }
.eyebrow { font-size: 14px; font-weight: 700; letter-spacing: .14em; text-transform: uppercase; color: var(--cyan); margin-bottom: 14px; }
.head h2 { font-size: clamp(32px, 5vw, 52px); font-weight: 800; }
.sub { max-width: 620px; margin: 18px auto 0; color: var(--muted); }

.video {
  margin: 44px auto 0; max-width: 980px; border-radius: 26px; overflow: hidden; background: #000;
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 40px 100px -30px rgba(139, 92, 255, 0.55), 0 0 0 1px rgba(56, 225, 255, 0.08);
}
.video video { width: 100%; height: auto; aspect-ratio: 16 / 9; background: #000; }

/* ---------- Feature grid ---------- */
.grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.card {
  position: relative; padding: 26px 24px 28px; border-radius: var(--radius);
  background: var(--card); border: 1px solid var(--line);
  transition: transform .25s, border-color .25s, background .25s;
}
.card::before {
  content: ""; position: absolute; inset: 0; border-radius: inherit; padding: 1px; opacity: 0; transition: opacity .25s;
  background: var(--grad);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude; pointer-events: none;
}
.card:hover { transform: translateY(-4px); background: rgba(255, 255, 255, 0.07); }
.card:hover::before { opacity: 1; }
.ic { box-sizing: content-box; width: 22px; height: 22px; padding: 11px; border-radius: 12px; margin-bottom: 18px; fill: none; stroke: var(--cyan); stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; background: rgba(139, 92, 255, 0.16); }
.card:nth-child(3n+2) .ic { stroke: var(--violet); }
.card:nth-child(3n) .ic { stroke: var(--pink); }
.card h3 { font-size: 19px; margin-bottom: 10px; }
.card p { font-size: 15px; line-height: 1.6; color: var(--muted); }

.priority {
  margin-top: 28px; padding: 34px 28px; text-align: center; border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(56, 225, 255, 0.08), rgba(139, 92, 255, 0.12), rgba(255, 79, 184, 0.1));
  border: 1px solid var(--line);
}
.priority h3 { font-size: clamp(20px, 3vw, 26px); }
.priority > p { margin-top: 16px; color: var(--muted); font-size: 15px; }
.chips { list-style: none; counter-reset: c; display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin: 22px 0 0; padding: 0; }
.chips li { counter-increment: c; display: inline-flex; align-items: center; gap: 10px; padding: 10px 18px; border-radius: 999px; background: rgba(0, 0, 0, 0.45); border: 1px solid var(--line); font-weight: 600; font-size: 15px; }
.chips li::before { content: counter(c); display: grid; place-items: center; width: 22px; height: 22px; border-radius: 50%; background: var(--grad); color: #07070c; font-size: 12px; font-weight: 800; }

/* ---------- Install ---------- */
.steps { list-style: none; margin: 0 auto; padding: 0; max-width: 820px; display: grid; grid-template-columns: minmax(0, 1fr); gap: 16px; }
.step { display: flex; gap: 22px; padding: 28px; border-radius: var(--radius); background: var(--card); border: 1px solid var(--line); }
.step .n { flex: none; display: grid; place-items: center; width: 44px; height: 44px; border-radius: 14px; font-weight: 800; font-size: 20px; color: #07070c; background: var(--grad); }
.step > div { flex: 1; min-width: 0; }
.step h3 { font-size: 21px; margin-bottom: 8px; }
.step p { color: var(--muted); font-size: 16px; }
.step p + p, .step p + .code, .step p + .btn { margin-top: 14px; }
.step .note { font-size: 14.5px; }
.code { display: flex; align-items: center; gap: 12px; min-width: 0; max-width: 100%; padding: 8px 8px 8px 16px; border-radius: 14px; background: #000; border: 1px solid var(--line); }
.code code { flex: 1; min-width: 0; overflow-x: auto; white-space: nowrap; font: 500 14px/1.5 ui-monospace, "SF Mono", Menlo, monospace; color: var(--cyan); }
.copy { appearance: none; flex: none; border: 0; cursor: pointer; min-height: 40px; padding: 0 16px; border-radius: 10px; font: 600 14px/1 inherit; color: var(--text); background: rgba(255, 255, 255, 0.1); transition: background .2s; }
.copy:hover { background: rgba(255, 255, 255, 0.18); }

.specs { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; max-width: 820px; margin: 28px auto 0; }
.specs > div { padding: 16px 20px; border-radius: 16px; background: var(--card); border: 1px solid var(--line); min-width: 0; }
.specs .wide { grid-column: 1 / -1; }
.specs dt { font-size: 13px; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.specs dd { margin: 4px 0 0; font-weight: 600; }
.specs code { display: block; overflow-wrap: anywhere; font: 500 12.5px/1.5 ui-monospace, "SF Mono", Menlo, monospace; color: var(--muted); }

/* ---------- Donate ---------- */
.donate {
  display: grid; grid-template-columns: minmax(0, 320px) minmax(0, 1fr); gap: 44px; align-items: center;
  max-width: 860px; margin: 0 auto; padding: 36px; border-radius: 28px;
  background: linear-gradient(135deg, rgba(56, 225, 255, 0.07), rgba(139, 92, 255, 0.1) 55%, rgba(255, 79, 184, 0.09));
  border: 1px solid var(--line);
}
.qr { padding: 3px; border-radius: 26px; background: var(--grad); box-shadow: 0 30px 70px -24px rgba(139, 92, 255, 0.7); }
.qr img { width: 100%; height: auto; border-radius: 4.4% / 3.9%; background: #fff; }
.dinfo h3 { font-size: 24px; margin-bottom: 10px; }
.dinfo > p { color: var(--muted); font-size: 16px; }
.bank { margin: 24px 0 0; display: grid; gap: 10px; }
.bank > div { padding: 12px 16px; border-radius: 14px; background: rgba(0, 0, 0, 0.4); border: 1px solid var(--line); min-width: 0; }
.bank dt { font-size: 12.5px; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.bank dd { margin: 3px 0 0; font-weight: 600; overflow-wrap: anywhere; }
.bank .acc { display: flex; align-items: center; justify-content: space-between; gap: 12px; font-size: 21px; letter-spacing: .04em; font-variant-numeric: tabular-nums; }
.bank .copy { min-height: 36px; padding: 0 14px; font-size: 13.5px; letter-spacing: 0; }

/* ---------- Footer ---------- */
.foot { border-top: 1px solid var(--line); padding: 36px 0 48px; }
.foot-in { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 18px; }
.foot p { max-width: 560px; font-size: 14px; color: var(--muted); }

/* ---------- Scroll reveal (chỉ bật khi có JS) ---------- */
.js .reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.js .reveal.in { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 1000px) { .grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 720px) {
  body { font-size: 16px; }
  .links { display: none; }
  .btn-sm { margin-left: auto; }
  .hero { padding-top: 48px; }
  .sec { padding: 68px 0; }
  .cta .btn { width: 100%; }
  .step { flex-direction: column; gap: 16px; padding: 22px; }
  .step .btn { width: 100%; white-space: nowrap; }
  .code { align-items: flex-start; }
  .code code { white-space: normal; overflow-wrap: anywhere; padding-top: 8px; }
  .specs { grid-template-columns: 1fr; }
  .donate { grid-template-columns: minmax(0, 1fr); gap: 28px; padding: 22px; }
  .qr { width: min(280px, 100%); margin-inline: auto; }
  .dinfo { text-align: center; }
  .bank { text-align: left; }
}
@media (max-width: 560px) { .grid { grid-template-columns: 1fr; } }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition-duration: .01ms !important; transition-delay: 0s !important; }
  .js .reveal { opacity: 1; transform: none; }
}