/* Bé Tập Đàn site: bright, rounded, the seven note colours of the app. */
:root {
  --ink: #1d2340;
  --muted: #5a6180;
  --line: #dfe5f2;
  --bg: #f4f8ff;
  --card: #ffffff;
  --primary: #c8326a;
  --do: #f0524a; --re: #f7902b; --mi: #f7c631; --fa: #4cbf6b;
  --sol: #3aa7e8; --la: #5965e0; --si: #a160e8;
  --do-soft: #fde4e2; --re-soft: #feecd9; --mi-soft: #fef6d6; --fa-soft: #e0f4e6;
  --sol-soft: #ddf0fc; --la-soft: #e4e6fb; --si-soft: #f0e5fc;
  --radius: 26px;
  --display: "Baloo 2", "Nunito", system-ui, sans-serif;
  --body: "Nunito", system-ui, -apple-system, "Segoe UI", sans-serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 18px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--primary); font-weight: 700; }
a:hover { text-decoration-thickness: 2px; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 20px; }
h1, h2, h3 { font-family: var(--display); line-height: 1.15; letter-spacing: -0.01em; }

/* Rainbow bar on top of every page */
.rainbow { height: 8px; background: linear-gradient(90deg, var(--do), var(--re), var(--mi), var(--fa), var(--sol), var(--la), var(--si)); }

/* Header */
.nav { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 18px 0; }
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; color: var(--ink); }
.brand img { width: 48px; height: 48px; border-radius: 12px; box-shadow: 0 3px 10px rgba(29, 35, 64, 0.15); }
.brand span { font-family: var(--display); font-size: 1.5rem; font-weight: 800; }
.nav ul { display: flex; gap: 22px; list-style: none; }
.nav ul a { color: var(--ink); text-decoration: none; font-weight: 700; }
.nav ul a:hover { color: var(--primary); }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 14px 26px; border-radius: 999px;
  background: var(--primary); color: #fff; text-decoration: none;
  font-family: var(--display); font-size: 1.15rem; font-weight: 700;
  box-shadow: 0 5px 0 #8f1f4a; transition: transform .12s, box-shadow .12s;
}
.btn:hover { transform: translateY(2px); box-shadow: 0 3px 0 #8f1f4a; }
.btn.ghost { background: #fff; color: var(--ink); box-shadow: 0 5px 0 var(--line); border: 2px solid var(--line); }
.appstore { display: inline-flex; align-items: center; gap: 12px; background: #111; color: #fff; text-decoration: none;
  padding: 10px 22px; border-radius: 14px; font-weight: 700; }
.appstore svg { width: 28px; height: 28px; fill: #fff; }
.appstore small { display: block; font-size: .72rem; font-weight: 600; opacity: .8; line-height: 1.1; }
.appstore b { display: block; font-size: 1.2rem; line-height: 1.1; }
.appstore[aria-disabled="true"] { opacity: .85; cursor: default; }

/* Footer */
footer { margin-top: 80px; background: var(--ink); color: #c9cde0; padding: 44px 0 36px; font-size: .95rem; }
footer .cols { display: flex; flex-wrap: wrap; gap: 28px; justify-content: space-between; align-items: flex-start; }
footer a { color: #fff; }
footer nav { display: flex; gap: 18px; flex-wrap: wrap; }

/* ---------- Legal documents (privacy, terms) ---------- */
.doc-hero { background: linear-gradient(135deg, #e9f4ff 0%, #f3ecff 55%, #fff4e3 100%); border-bottom: 1px solid var(--line); }
.doc-hero .wrap { display: flex; align-items: center; gap: 28px; padding-top: 44px; padding-bottom: 44px; }
.doc-hero img { width: 92px; height: 92px; border-radius: 22px; box-shadow: 0 10px 24px rgba(29,35,64,.18); flex: none; }
.doc-hero .crumb { font-size: .9rem; font-weight: 700; color: var(--muted); }
.doc-hero .crumb a { color: var(--muted); text-decoration: none; }
.doc-hero h1 { font-size: clamp(2.1rem, 4.6vw, 3.1rem); margin: 4px 0 12px; }
.meta { display: flex; flex-wrap: wrap; gap: 8px; }
.meta span { display: inline-flex; align-items: center; gap: 6px; background: rgba(255,255,255,.8); border: 1px solid var(--line);
  border-radius: 999px; padding: 4px 12px; font-size: .88rem; font-weight: 700; color: #3a4166; }
.meta svg { width: 15px; height: 15px; }

.glance { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin: 36px 0 8px; }
.glance div { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 18px 18px 16px; }
.glance .ic { width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center; margin-bottom: 10px; }
.glance .ic svg { width: 22px; height: 22px; }
.glance b { display: block; font-size: 1.02rem; margin-bottom: 2px; }
.glance span { font-size: .92rem; color: var(--muted); line-height: 1.5; display: block; }

.doc { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 56px; align-items: start; padding-top: 28px; }
.doc nav.toc { position: sticky; top: 24px; }
.doc nav.toc p { font-size: .78rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 10px; }
.doc nav.toc ol { list-style: none; border-left: 2px solid var(--line); }
.doc nav.toc a { display: block; padding: 6px 0 6px 16px; margin-left: -2px; border-left: 2px solid transparent;
  color: var(--muted); text-decoration: none; font-weight: 600; font-size: .95rem; line-height: 1.4; }
.doc nav.toc a:hover { color: var(--ink); }
.doc nav.toc a.on { color: var(--primary); border-left-color: var(--primary); font-weight: 800; }

.doc .body { max-width: 720px; }
.doc .body section { padding: 0 0 34px; margin-bottom: 34px; border-bottom: 1px solid var(--line); scroll-margin-top: 20px; }
.doc .body section:last-of-type { border-bottom: 0; }
.doc h2 { display: flex; align-items: center; gap: 12px; font-size: 1.55rem; margin-bottom: 14px; }
.doc h2 .n { flex: none; width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center;
  font-size: 1rem; color: #fff; background: var(--ink); }
.doc .body section:nth-of-type(7n+1) .n { background: var(--do); } .doc .body section:nth-of-type(7n+2) .n { background: var(--re); }
.doc .body section:nth-of-type(7n+3) .n { background: #d9a400; } .doc .body section:nth-of-type(7n+4) .n { background: var(--fa); }
.doc .body section:nth-of-type(7n+5) .n { background: var(--sol); } .doc .body section:nth-of-type(7n+6) .n { background: var(--la); }
.doc .body section:nth-of-type(7n+7) .n { background: var(--si); }
.doc p, .doc li { color: #343b5c; font-size: 1.02rem; }
.doc p { margin-bottom: 12px; }
.doc ul { margin: 4px 0 14px 0; list-style: none; }
.doc ul li { position: relative; padding-left: 22px; margin-bottom: 8px; }
.doc ul li::before { content: ""; position: absolute; left: 4px; top: .65em; width: 7px; height: 7px; border-radius: 50%; background: var(--sol); }
.doc strong { color: var(--ink); }

.table { width: 100%; border-collapse: separate; border-spacing: 0; margin: 8px 0 16px; border: 1px solid var(--line); border-radius: 16px; overflow: hidden; font-size: .95rem; }
.table th { background: #f2f5fc; text-align: left; font-weight: 800; padding: 12px 14px; color: var(--ink); }
.table td { padding: 12px 14px; border-top: 1px solid var(--line); vertical-align: top; color: #343b5c; }
.table td:first-child { font-weight: 800; color: var(--ink); white-space: nowrap; }

.note { display: flex; gap: 12px; background: #f2f9f4; border: 1px solid #cfe9d7; border-radius: 16px; padding: 14px 16px; margin: 8px 0 14px; }
.note.warn { background: #fff7e8; border-color: #f4dfb0; }
.note svg { flex: none; width: 22px; height: 22px; margin-top: 3px; }
.note p { margin: 0; }

.plans { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin: 8px 0 16px; }
.plans div { border: 1px solid var(--line); border-radius: 14px; padding: 12px; background: #fff; }
.plans b { display: block; font-size: .95rem; }
.plans em { display: block; font-style: normal; font-family: var(--display); font-size: 1.35rem; color: var(--primary); line-height: 1.2; }
.plans span { font-size: .82rem; color: var(--muted); font-weight: 700; }

ol.howto { list-style: none; counter-reset: s; margin: 6px 0 14px; }
ol.howto li { counter-increment: s; position: relative; padding: 2px 0 10px 44px; }
ol.howto li::before { content: counter(s); position: absolute; left: 0; top: 0; width: 30px; height: 30px; border-radius: 50%;
  background: var(--sol-soft); color: #0b6293; font-weight: 800; display: grid; place-items: center; }

.contact { display: flex; align-items: center; gap: 18px; background: var(--ink); color: #fff; border-radius: 22px; padding: 22px 24px; margin: 6px 0 34px; }
.contact svg { width: 40px; height: 40px; flex: none; }
.contact b { display: block; font-family: var(--display); font-size: 1.3rem; }
.contact span { color: #c9cde0; }
.contact a { color: #fff; }

.en-card { background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 26px 28px; }
.en-card h2 { font-size: 1.3rem; }
.en-card .lang { display: inline-block; font-size: .75rem; font-weight: 800; letter-spacing: .1em; background: #f2f5fc; border-radius: 6px; padding: 2px 8px; margin-bottom: 8px; color: var(--muted); }

@media (max-width: 960px) {
  .doc { grid-template-columns: 1fr; gap: 0; }
  .doc nav.toc { position: static; background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 16px 18px; margin-bottom: 28px; }
  .glance { grid-template-columns: 1fr 1fr; }
  .plans { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px) {
  .doc-hero .wrap { flex-direction: column; align-items: flex-start; gap: 16px; padding-top: 28px; padding-bottom: 28px; }
  .doc-hero img { width: 68px; height: 68px; border-radius: 16px; }
  .glance { grid-template-columns: 1fr; }
  .table td:first-child { white-space: normal; }
}

@media (max-width: 720px) {
  body { font-size: 17px; }
  .nav ul { display: none; }
}

/* ---------- Landing ---------- */
section { padding: 64px 0; }
.eyebrow { display: inline-block; font-weight: 800; font-size: .85rem; letter-spacing: .08em; text-transform: uppercase;
  color: var(--primary); background: var(--do-soft); padding: 4px 12px; border-radius: 999px; margin-bottom: 12px; }
.section-title { font-size: clamp(1.9rem, 4.2vw, 2.8rem); margin-bottom: 12px; }
.lead { font-size: 1.2rem; color: var(--muted); max-width: 720px; }
.center { text-align: center; }
.center .lead { margin: 0 auto; }

.hero { padding: 28px 0 56px; position: relative; overflow: hidden;
  background: radial-gradient(1200px 500px at 70% 0%, #dff1ff 0%, transparent 60%), radial-gradient(800px 400px at 0% 100%, #fff3d6 0%, transparent 60%); }
.hero .grid { display: grid; grid-template-columns: 1.02fr 1.2fr; gap: 40px; align-items: center; }
.hero h1 { font-size: clamp(2.8rem, 7vw, 4.6rem); line-height: 1.02; }
.hero h1 .rb span:nth-child(1) { color: var(--do); } .hero h1 .rb span:nth-child(2) { color: var(--re); }
.hero h1 .rb span:nth-child(3) { color: #d9a400; } .hero h1 .rb span:nth-child(4) { color: var(--fa); }
.hero h1 .rb span:nth-child(5) { color: var(--sol); } .hero h1 .rb span:nth-child(6) { color: var(--la); }
.hero h1 .rb span:nth-child(7) { color: var(--si); }
.hero p.tag { font-size: 1.35rem; font-weight: 700; margin: 14px 0 10px; }
.hero p.sub { color: var(--muted); margin-bottom: 26px; }
.hero .ctas { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.hero .note { margin-top: 14px; font-size: .95rem; color: var(--muted); }
.device { background: #1d2340; border-radius: 34px; padding: 16px; box-shadow: 0 30px 60px rgba(29, 35, 64, .25); transform: rotate(1.5deg); }
.device img { border-radius: 20px; }
.hero .art { position: relative; }
.float { position: absolute; width: 120px; filter: drop-shadow(0 10px 14px rgba(29,35,64,.25)); animation: bob 3.2s ease-in-out infinite; }
.float.a { left: -46px; bottom: -30px; width: 130px; }
.float.b { right: -26px; top: -46px; width: 110px; animation-delay: -1.2s; }
@keyframes bob { 50% { transform: translateY(-12px) rotate(-3deg); } }
@media (prefers-reduced-motion: reduce) { .float { animation: none; } }

.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 8px; }
.stat { background: #fff; border: 2px solid var(--line); border-radius: 22px; padding: 18px; text-align: center; }
.stat b { display: block; font-family: var(--display); font-size: 2.4rem; line-height: 1; }
.stat span { color: var(--muted); font-weight: 700; }
.stat:nth-child(1) b { color: var(--do); } .stat:nth-child(2) b { color: var(--fa); }
.stat:nth-child(3) b { color: var(--sol); } .stat:nth-child(4) b { color: var(--si); }

.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 36px; }
.step { background: #fff; border-radius: var(--radius); border: 2px solid var(--line); overflow: hidden; display: flex; flex-direction: column; }
.step img { border-bottom: 2px solid var(--line); }
.step .txt { padding: 20px 22px 24px; }
.step h3 { font-size: 1.45rem; margin-bottom: 6px; }
.step .n { display: inline-grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; color: #fff; font-family: var(--display); font-size: 1.2rem; margin-right: 8px; }
.step p { color: var(--muted); }

.lands { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 18px; margin-top: 36px; }
.land { border-radius: var(--radius); padding: 20px 20px 22px; position: relative; overflow: hidden; border: 2px solid rgba(29,35,64,.06); }
.land img { width: 84px; height: 84px; object-fit: contain; position: absolute; right: 10px; top: 10px; }
.land .k { font-weight: 800; font-size: .85rem; opacity: .75; padding-right: 84px; }
.land h3 { font-size: 1.45rem; margin: 2px 0 10px; padding-right: 84px; min-height: 2.4em; display: flex; align-items: flex-end; }
.land p { font-size: .98rem; }
.land .songs { margin-top: 10px; display: flex; flex-wrap: wrap; gap: 6px; }
.land .songs span { background: rgba(255,255,255,.75); border-radius: 999px; padding: 2px 10px; font-size: .85rem; font-weight: 700; }

.split { display: grid; grid-template-columns: 1fr 1.15fr; gap: 44px; align-items: center; }
.split.rev { grid-template-columns: 1.15fr 1fr; }
.shot { border-radius: 22px; border: 6px solid #fff; box-shadow: 0 18px 40px rgba(29,35,64,.16); }
.ticks { list-style: none; margin-top: 18px; }
.ticks li { padding-left: 36px; position: relative; margin-bottom: 12px; font-weight: 600; }
.ticks li::before { content: "♪"; position: absolute; left: 0; top: -2px; width: 26px; height: 26px; border-radius: 50%;
  background: var(--fa-soft); color: #1b7a3d; display: grid; place-items: center; font-weight: 800; }

.stickers { display: grid; grid-template-columns: repeat(7, 1fr); gap: 10px; margin-top: 30px; }
.stickers img { width: 100%; transition: transform .2s; }
.stickers img:nth-child(odd) { transform: rotate(-5deg); } .stickers img:nth-child(even) { transform: rotate(4deg); }
.stickers img:hover { transform: scale(1.12) rotate(0); }

.cards3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 34px; }
.card { background: #fff; border-radius: var(--radius); border: 2px solid var(--line); padding: 24px; }
.card .ic { width: 56px; height: 56px; border-radius: 18px; display: grid; place-items: center; font-size: 1.8rem; margin-bottom: 12px; }
.card h3 { font-size: 1.35rem; margin-bottom: 6px; }
.card p { color: var(--muted); }

.parent { background: var(--ink); color: #fff; border-radius: 34px; padding: 44px clamp(22px, 5vw, 52px); }
.parent .section-title { color: #fff; }
.parent .lead { color: #c9cde0; }
.parent .grid4 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px 30px; margin-top: 26px; }
.parent .grid4 div { padding-left: 46px; position: relative; }
.parent .grid4 b { display: block; font-family: var(--display); font-size: 1.25rem; }
.parent .grid4 span { color: #c9cde0; }
.parent .grid4 i { position: absolute; left: 0; top: 2px; font-style: normal; font-size: 1.6rem; }
.safe { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 28px; }
.safe span { background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.2); border-radius: 999px; padding: 6px 14px; font-weight: 700; }

.prices { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 34px; }
.price { background: #fff; border: 2px solid var(--line); border-radius: var(--radius); padding: 22px; display: flex; flex-direction: column; }
.price.best { border: 4px solid var(--ink); }
.price .tag { display: inline-block; align-self: flex-start; font-size: .78rem; font-weight: 800; padding: 3px 10px; border-radius: 999px; background: var(--mi); margin-bottom: 8px; }
.price h3 { font-size: 1.35rem; }
.price s { color: var(--muted); font-weight: 700; }
.price .amt { font-family: var(--display); font-size: 2.1rem; color: var(--primary); line-height: 1.1; }
.price .per { color: var(--muted); font-weight: 700; }
.price ul { margin: 12px 0 0 18px; color: var(--muted); font-size: .95rem; }
.price.free .amt { color: var(--fa); }
.small { font-size: .9rem; color: var(--muted); margin-top: 16px; }

.faq { max-width: 820px; margin: 30px auto 0; }
.faq details { background: #fff; border: 2px solid var(--line); border-radius: 20px; padding: 16px 22px; margin-bottom: 12px; }
.faq summary { cursor: pointer; font-weight: 800; font-size: 1.08rem; list-style: none; }
.faq summary::after { content: "+"; float: right; font-family: var(--display); font-size: 1.4rem; line-height: 1; color: var(--primary); }
.faq details[open] summary::after { content: "–"; }
.faq p { margin-top: 10px; color: var(--muted); }

.final { text-align: center; background: linear-gradient(135deg, var(--sol-soft), var(--si-soft)); border-radius: 34px; padding: 48px 24px; }
.final img { width: 110px; height: 110px; border-radius: 26px; margin: 0 auto 16px; box-shadow: 0 10px 24px rgba(29,35,64,.2); }

@media (max-width: 900px) {
  .hero .grid, .split, .split.rev { grid-template-columns: 1fr; }
  .split.rev .shot { order: -1; }
  .steps, .cards3 { grid-template-columns: 1fr; }
  .prices { grid-template-columns: 1fr 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .stickers { grid-template-columns: repeat(4, 1fr); }
  .parent .grid4 { grid-template-columns: 1fr; }
  .float.a { left: -10px; } .float.b { right: -6px; }
}
@media (max-width: 520px) { .prices { grid-template-columns: 1fr; } }