:root {
  --bg: #0b1210;
  --ink: #eef2ea;
  --ink-soft: rgba(238, 242, 234, .72);
  --ink-mute: rgba(238, 242, 234, .5);
  --glass: rgba(20, 30, 26, .45);
  --glass-soft: rgba(255, 255, 255, .06);
  --line: rgba(255, 255, 255, .12);
  --accent: #f2d36b;
  --accent-ink: #1a1a10;
  --leaf: #b9d98c;
  --radius: 28px;
  --serif: "DM Serif Display", Georgia, serif;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.6 var(--sans);
  min-height: 100vh;
  overflow-x: hidden;
}
a { color: inherit; }
h1, h2, h3 { margin: 0; font-weight: 400; }

/* ---------- Background scene ---------- */
.scene { position: fixed; inset: 0; z-index: -1; overflow: hidden; }
.sky {
  position: absolute; inset: 0;
  background:
    radial-gradient(60% 50% at 70% 20%, rgba(242, 211, 107, .14), transparent 70%),
    radial-gradient(70% 60% at 20% 30%, rgba(90, 140, 110, .35), transparent 70%),
    linear-gradient(180deg, #1c2b33 0%, #13201b 45%, #0b1210 100%);
}
.trees { position: absolute; left: 0; width: 100%; bottom: 0; }
.trees-back { height: 55%; fill: #16251f; opacity: .9; }
.trees-front { height: 35%; fill: #0a120f; }
.fireflies i {
  position: absolute; width: 4px; height: 4px; border-radius: 50%;
  background: #f6e7a1; box-shadow: 0 0 12px 3px rgba(246, 231, 161, .55);
  opacity: 0; animation: drift 14s ease-in-out infinite;
}
.fireflies i:nth-child(1) { left: 12%; top: 62%; animation-delay: 0s; }
.fireflies i:nth-child(2) { left: 28%; top: 72%; animation-delay: 3s; }
.fireflies i:nth-child(3) { left: 45%; top: 58%; animation-delay: 6s; }
.fireflies i:nth-child(4) { left: 63%; top: 70%; animation-delay: 2s; }
.fireflies i:nth-child(5) { left: 78%; top: 60%; animation-delay: 8s; }
.fireflies i:nth-child(6) { left: 88%; top: 75%; animation-delay: 5s; }
.fireflies i:nth-child(7) { left: 36%; top: 82%; animation-delay: 10s; }
.fireflies i:nth-child(8) { left: 70%; top: 85%; animation-delay: 12s; }
@keyframes drift {
  0%, 100% { opacity: 0; transform: translate(0, 0); }
  30% { opacity: .9; }
  60% { opacity: .5; transform: translate(30px, -40px); }
}
@media (prefers-reduced-motion: reduce) {
  .fireflies i { animation: none; opacity: .5; }
  html { scroll-behavior: auto; }
}

/* ---------- Glass ---------- */
.glass {
  background: var(--glass);
  border: 1px solid var(--line);
  -webkit-backdrop-filter: blur(22px) saturate(120%);
  backdrop-filter: blur(22px) saturate(120%);
}
.glass-soft {
  background: var(--glass-soft);
  border: 1px solid var(--line);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}

.frame {
  max-width: 1200px;
  margin: 32px auto;
  border-radius: var(--radius);
  padding: 28px 48px 32px;
  box-shadow: 0 30px 80px rgba(0, 0, 0, .45);
}

/* ---------- Nav ---------- */
.nav { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-family: var(--serif); font-size: 26px; text-decoration: none; letter-spacing: .01em; }
.pill { display: flex; gap: 4px; padding: 5px; border-radius: 999px; }
.pill a {
  text-decoration: none; font-size: 14px; font-weight: 500;
  padding: 8px 16px; border-radius: 999px; color: var(--ink-soft);
  transition: background .2s, color .2s;
}
.pill a:hover { background: rgba(255, 255, 255, .08); color: var(--ink); }
.pill a.pill-accent { background: var(--accent); color: var(--accent-ink); }

/* ---------- Hero ---------- */
.hero {
  display: grid; grid-template-columns: 1.3fr 1fr; gap: 48px;
  align-items: center; padding: 72px 0 56px;
}
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border-radius: 999px; font-size: 13px; color: var(--ink-soft); margin: 0 0 24px;
}
.dot { width: 7px; height: 7px; border-radius: 50%; background: var(--leaf); box-shadow: 0 0 8px var(--leaf); }
h1 { font-family: var(--serif); font-size: clamp(44px, 6.5vw, 84px); line-height: 1.02; letter-spacing: -.01em; }
.lead { font-size: 20px; color: var(--ink); margin: 24px 0 8px; }
.sub { color: var(--ink-soft); max-width: 46ch; margin: 0; }
.cta { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 32px; }

.btn {
  display: inline-block; text-decoration: none; font-weight: 600; font-size: 15px;
  padding: 14px 26px; border-radius: 999px; transition: transform .15s, background .2s;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--accent); color: var(--accent-ink); }
.btn-ghost { border: 1px solid var(--line); background: rgba(255, 255, 255, .04); }
.btn-ghost:hover { background: rgba(255, 255, 255, .1); }
.btn-sm { padding: 10px 18px; font-size: 14px; }

.hero-card { border-radius: 24px; padding: 28px; }
.card-kicker { margin: 0 0 18px; font-size: 13px; text-transform: uppercase; letter-spacing: .12em; color: var(--ink-mute); }
.layers { list-style: none; margin: 0; padding: 0; display: grid; gap: 16px; }
.layers li { display: grid; grid-template-columns: 116px 1fr 44px; align-items: center; gap: 12px; font-size: 15px; transition: opacity .2s; }
.layers li.is-off { opacity: .55; }
.layers label { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; }
.layer-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--c); box-shadow: 0 0 8px var(--c); flex: none; }
.layers output { text-align: right; font-variant-numeric: tabular-nums; font-size: 14px; color: var(--ink-soft); }

/* ---------- Mixer ---------- */
.mixer-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 18px; }
.mixer-head .card-kicker { margin: 0; }
.play {
  width: 56px; height: 56px; border-radius: 50%; border: 0; cursor: pointer;
  background: var(--accent); color: var(--accent-ink); display: grid; place-items: center;
  box-shadow: 0 0 0 6px rgba(242, 211, 107, .12); transition: transform .15s;
}
.play:hover { transform: scale(1.05); }
.play svg { width: 24px; height: 24px; fill: currentColor; }
.play .i-pause, .play.is-playing .i-play { display: none; }
.play.is-playing .i-pause { display: block; }
.play:focus-visible, .btn:focus-visible, select:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

input[type=range] {
  -webkit-appearance: none; appearance: none; width: 100%; height: 28px; margin: 0;
  background: transparent; cursor: pointer; touch-action: none;
}
input[type=range]::-webkit-slider-runnable-track {
  height: 6px; border-radius: 6px;
  background: linear-gradient(var(--c), var(--c)) 0 / calc(var(--v, .5) * 100%) 100% no-repeat, rgba(255, 255, 255, .12);
}
input[type=range]::-moz-range-track { height: 6px; border-radius: 6px; background: rgba(255, 255, 255, .12); }
input[type=range]::-moz-range-progress { height: 6px; border-radius: 6px; background: var(--c); }
input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none; width: 22px; height: 22px; border-radius: 50%; margin-top: -8px;
  background: #f6efd2; border: 0; box-shadow: 0 2px 8px rgba(0, 0, 0, .4);
}
input[type=range]::-moz-range-thumb { width: 22px; height: 22px; border-radius: 50%; background: #f6efd2; border: 0; }
input[type=range]:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; border-radius: 6px; }

.mixer-foot { margin-top: 22px; padding-top: 18px; border-top: 1px solid var(--line); }
.timer { display: flex; align-items: center; justify-content: space-between; gap: 12px; font-size: 15px; }
.timer select {
  font: inherit; color: var(--ink); background: rgba(255, 255, 255, .06);
  border: 1px solid var(--line); border-radius: 999px; padding: 8px 14px;
}
.timer select option { color: #111; }
.timer-status { min-height: 1.4em; margin: 10px 0 0; font-size: 14px; color: var(--leaf); }
.mixer-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 10px; }
.mixer-actions .btn { color: var(--ink); cursor: pointer; font-family: inherit; }
.card-note { margin: 22px 0 0; font-size: 14px; color: var(--ink-mute); }

/* ---------- Sections ---------- */
.section { padding: 48px 0; border-top: 1px solid var(--line); }
.section h2 { font-family: var(--serif); font-size: clamp(30px, 4vw, 42px); }
.section-sub { color: var(--ink-soft); margin: 8px 0 28px; }

.creators { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.creator { border-radius: 22px; padding: 28px; border-top: 3px solid var(--accent); }
.creator h3 { font-family: var(--serif); font-size: 28px; color: var(--accent); }
.creator p { color: var(--ink-soft); margin: 10px 0 16px; }
.tags { list-style: none; padding: 0; margin: 0 0 22px; display: flex; flex-wrap: wrap; gap: 8px; }
.tags li { font-size: 12px; padding: 4px 10px; border-radius: 999px; border: 1px solid var(--line); color: var(--ink-soft); }

.tips { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 28px; }
.tip { border-radius: 20px; padding: 24px; }
.tip h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
.tip p { margin: 0; color: var(--ink-soft); font-size: 15px; }

.support { border-radius: 24px; padding: 40px; margin: 48px 0 8px; border-top: 1px solid var(--line); text-align: center; }
.support p { max-width: 56ch; margin: 14px auto 0; color: var(--ink-soft); }
.letter { max-width: 58ch; margin: 18px auto 0; text-align: left; }
.letter p { margin: 12px 0 0; }
.letter .sign { font-family: var(--serif); font-size: 19px; color: var(--ink); }
.letter .sign span { display: block; color: var(--accent); }
.donate { margin-top: 28px; padding-top: 24px; border-top: 1px solid var(--line); }
.donate-label { font-size: 13px; text-transform: uppercase; letter-spacing: .12em; color: var(--ink-mute) !important; margin: 0 auto 14px !important; }
.amounts { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; }
.amounts .btn { min-width: 76px; text-align: center; }
.support .small { font-size: 13px; }
.supporters { margin-top: 28px; padding-top: 22px; border-top: 1px solid var(--line); }
.supporters ul { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 18px; color: var(--ink-soft); }
.muted { color: var(--ink-mute); font-size: 14px; }

/* ---------- Newsletter ---------- */
.newsletter { display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: 8px 16px; margin: 28px 0 0; }
.newsletter-text { margin: 0; font-size: 14px; color: var(--ink-mute); }
.newsletter .signup-form { gap: 8px; }
.newsletter .signup-form input { width: 220px; padding: 9px 16px; font-size: 14px; }
.newsletter .signup-form .btn { padding: 9px 18px; font-size: 14px; color: var(--ink); }
.newsletter .signup-msg { text-align: center; margin: 2px 0 0; font-size: 13px; }
.signup-form { display: flex; flex-wrap: wrap; gap: 10px; }
.signup-form input {
  flex: 1 1 220px; min-width: 0; font: inherit; color: var(--ink);
  background: rgba(255, 255, 255, .06); border: 1px solid var(--line);
  border-radius: 999px; padding: 13px 20px;
}
.signup-form input::placeholder { color: var(--ink-mute); }
.signup-form input:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.signup-form button { border: 0; cursor: pointer; font-family: inherit; }
.signup-form button[disabled] { opacity: .6; cursor: default; }
.signup-msg { flex-basis: 100%; min-height: 1.4em; margin: 4px 0 0 8px; font-size: 14px; color: var(--leaf); }
.signup-msg.is-error { color: #f0a08a; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- Footer ---------- */
.footer { border-top: 1px solid var(--line); margin-top: 40px; padding-top: 24px; text-align: center; }
.footer .links { display: flex; justify-content: center; gap: 28px; flex-wrap: wrap; }
.footer .links a { text-decoration: none; font-size: 13px; letter-spacing: .2em; text-transform: uppercase; color: var(--ink-soft); }
.disclaimer { font-size: 13px; color: var(--ink-mute); max-width: 60ch; margin: 18px auto 6px; }

/* ---------- Mobile ---------- */
@media (max-width: 860px) {
  .frame { margin: 0; border-radius: 0; padding: 20px 16px 28px; border-left: 0; border-right: 0; }
  .nav { flex-direction: column; align-items: stretch; }
  .brand { justify-content: center; }
  .pill { justify-content: center; flex-wrap: wrap; border-radius: 22px; }
  .pill a { padding: 7px 12px; font-size: 13px; white-space: nowrap; }
  .hero { grid-template-columns: 1fr; gap: 32px; padding: 40px 0 32px; }
  .tips { grid-template-columns: 1fr; }
  .support { padding: 28px 20px; }
  .newsletter .signup-form { justify-content: center; }
  .newsletter .signup-form input { width: 100%; max-width: 240px; flex: 1; }
}

/* ---------- Text pages ---------- */
.prose { max-width: 68ch; }
.prose h1 { font-family: var(--serif); font-size: clamp(36px, 5vw, 52px); }
.prose h2 { font-family: var(--sans); font-size: 18px; font-weight: 600; margin: 28px 0 6px; }
.prose p { color: var(--ink-soft); margin: 8px 0; }
.prose a:not(.btn) { color: var(--accent); }
.prose code { font-size: .9em; }
.footer .muted a { color: inherit; }

/* ---------- Mixer: chọn phiên bản âm ---------- */
.layers li .variant {
  grid-column: 2 / 4; justify-self: start; margin-top: -6px; max-width: 100%;
  font: inherit; font-size: 13px; color: var(--ink-soft);
  background: rgba(255, 255, 255, .05); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px;
}
.layers li .variant option { color: #111; }
.layers li .variant[hidden] { display: none; }