/* BillBox website — calm, large type, lots of air (Apple-style product pages). */
:root {
  --ink: #1d1d1f; --muted: #6e6e73; --line: #d2d2d7; --bg: #ffffff; --alt: #f5f5f7; --brand: #4f46e5; --brand2: #7c3aed;
  --link: #0066cc; --card: #ffffff; --nav: rgba(255, 255, 255, .72); --dark: #000; --dark-ink: #f5f5f7;
  --radius: 22px; --max: 1080px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --ink: #f5f5f7; --muted: #a1a1a6; --line: #424245; --bg: #000; --alt: #161617; --card: #1d1d1f; --nav: rgba(22, 22, 23, .72); --link: #2997ff; }
}
:root[data-theme="dark"] { --ink: #f5f5f7; --muted: #a1a1a6; --line: #424245; --bg: #000; --alt: #161617; --card: #1d1d1f; --nav: rgba(22, 22, 23, .72); --link: #2997ff; }
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 17px/1.47 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; letter-spacing: -.022em; overflow-x: hidden; }
a { color: var(--link); text-decoration: none; } a:hover { text-decoration: underline; }
img, video { max-width: 100%; display: block; }
.wrap { max-width: var(--max); margin: 0 auto; padding: 0 22px; }

/* nav */
.nav { position: sticky; top: 0; z-index: 50; background: var(--nav); backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px); border-bottom: 1px solid color-mix(in srgb, var(--line) 50%, transparent); }
.nav .wrap { display: flex; align-items: center; height: 48px; gap: 22px; font-size: 13px; }
.nav .brand { display: flex; align-items: center; gap: 8px; font-weight: 600; color: var(--ink); font-size: 15px; }
.nav .brand img { width: 22px; height: 22px; border-radius: 6px; }
.nav .links { display: flex; gap: 22px; flex: 1; justify-content: center; }
.nav .links a { color: var(--ink); opacity: .85; } .nav .links a:hover { opacity: 1; text-decoration: none; }
.nav .cta { background: var(--brand); color: #fff; border-radius: 980px; padding: 5px 13px; font-weight: 500; }
.nav .cta:hover { text-decoration: none; filter: brightness(1.08); }
.menu-btn { display: none; background: none; border: 0; color: var(--ink); font-size: 20px; }
@media (max-width: 760px) {
  .nav .links { display: none; position: absolute; top: 48px; left: 0; right: 0; flex-direction: column; gap: 0; background: var(--bg); border-bottom: 1px solid var(--line); padding: 8px 22px 16px; }
  .nav .links.open { display: flex; } .nav .links a { padding: 10px 0; font-size: 17px; border-bottom: 1px solid var(--line); }
  .menu-btn { display: block; margin-left: auto; } .nav .cta { display: none; }
}

/* sections */
section { padding: 96px 0; }
section.alt { background: var(--alt); }
section.dark { background: var(--dark); color: var(--dark-ink); }
.eyebrow { color: var(--brand); font-weight: 600; font-size: 17px; margin: 0 0 8px; letter-spacing: -.01em; }
h1, h2, h3 { letter-spacing: -.03em; line-height: 1.07; margin: 0; }
h1 { font-size: clamp(44px, 8vw, 80px); font-weight: 700; }
h2 { font-size: clamp(32px, 5.4vw, 56px); font-weight: 700; }
h3 { font-size: clamp(21px, 2.6vw, 28px); font-weight: 600; line-height: 1.14; }
.lead { font-size: clamp(19px, 2.4vw, 26px); line-height: 1.32; color: var(--muted); margin: 18px auto 0; max-width: 760px; font-weight: 500; letter-spacing: -.015em; }
.center { text-align: center; }
.grad { background: linear-gradient(90deg, var(--brand), var(--brand2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.btns { display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; margin-top: 28px; align-items: center; }
.btn { display: inline-block; background: var(--brand); color: #fff; border-radius: 980px; padding: 12px 24px; font-size: 17px; font-weight: 500; border: 0; cursor: pointer; }
.btn:hover { text-decoration: none; filter: brightness(1.08); }
.btn.ghost { background: transparent; color: var(--link); padding: 12px 6px; }
.btn.ghost::after { content: " ›"; }
.btn[disabled] { opacity: .5; cursor: default; }

.hero { padding: 76px 0 40px; text-align: center; overflow: hidden; }
.hero .video { margin: 48px auto 0; max-width: 1000px; border-radius: 26px; overflow: hidden; box-shadow: 0 40px 80px -40px rgba(30, 27, 75, .45); background: #eef0ff; aspect-ratio: 16/9; }
.hero .video video { width: 100%; height: 100%; object-fit: cover; }

.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; margin-top: 48px; }
.tile { background: var(--card); border-radius: var(--radius); padding: 34px 30px; position: relative; overflow: hidden; }
section:not(.alt) .tile { background: var(--alt); }
.tile .ic { width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center; background: linear-gradient(135deg, var(--brand), var(--brand2)); color: #fff; font-size: 22px; margin-bottom: 18px; }
.tile p { color: var(--muted); margin: 10px 0 0; }
.tile ul { margin: 12px 0 0; padding-left: 18px; color: var(--muted); } .tile li { margin: 4px 0; }

.platforms { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; margin-top: 44px; }
.plat { background: var(--card); border-radius: var(--radius); padding: 26px 22px; text-align: center; color: var(--ink); transition: transform .25s ease, box-shadow .25s ease; }
.plat:hover { text-decoration: none; transform: translateY(-4px); box-shadow: 0 24px 40px -24px rgba(0, 0, 0, .25); }
.plat .glyph { font-size: 40px; height: 52px; }
.plat b { display: block; font-size: 21px; margin-top: 8px; } .plat span { color: var(--muted); font-size: 14px; } .plat i { display: block; font-style: normal; color: var(--link); margin-top: 10px; font-size: 15px; }

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.split.rev > :first-child { order: 2; }
@media (max-width: 860px) { .split { grid-template-columns: 1fr; } .split.rev > :first-child { order: 0; } }
.split video, .split img { border-radius: var(--radius); box-shadow: 0 30px 60px -36px rgba(0, 0, 0, .4); }
.checks { list-style: none; padding: 0; margin: 22px 0 0; }
.checks li { padding: 10px 0 10px 32px; position: relative; border-bottom: 1px solid var(--line); }
.checks li::before { content: "✓"; position: absolute; left: 0; top: 9px; width: 22px; height: 22px; border-radius: 50%; background: color-mix(in srgb, var(--brand) 14%, transparent); color: var(--brand); font-size: 13px; display: grid; place-items: center; font-weight: 700; }
.checks li.soon::before { content: "…"; background: var(--alt); color: var(--muted); }
.checks li b { font-weight: 600; } .checks li span { color: var(--muted); }

.specs { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 0; margin-top: 36px; border-top: 1px solid var(--line); }
.specs div { padding: 20px 16px 20px 0; border-bottom: 1px solid var(--line); }
.specs b { display: block; font-size: 14px; color: var(--muted); font-weight: 500; } .specs span { font-size: 19px; font-weight: 600; }

/* pricing */
.prices { display: grid; grid-template-columns: repeat(auto-fit, minmax(270px, 1fr)); gap: 20px; margin-top: 48px; }
.price { background: var(--card); border-radius: var(--radius); padding: 34px 30px; border: 1px solid var(--line); display: flex; flex-direction: column; }
.price.best { border: 2px solid var(--brand); }
.price .tag { font-size: 12px; font-weight: 600; color: var(--brand); text-transform: uppercase; letter-spacing: .04em; min-height: 18px; }
.price h3 { margin-top: 6px; } .price .amt { font-size: 48px; font-weight: 700; letter-spacing: -.03em; margin: 14px 0 0; } .price .amt small { font-size: 17px; color: var(--muted); font-weight: 500; }
.price ul { list-style: none; padding: 0; margin: 18px 0 24px; color: var(--muted); flex: 1; } .price li { padding: 6px 0; border-bottom: 1px solid var(--line); font-size: 15px; }
.price .btn { text-align: center; }

/* forms (buy) */
.card { text-align: left; background: var(--card); border-radius: var(--radius); padding: 30px; border: 1px solid var(--line); }
label { display: block; font-size: 14px; color: var(--muted); margin: 14px 0 6px; }
input, select { width: 100%; font: inherit; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--line); background: var(--bg); color: var(--ink); }
input:focus, select:focus { outline: 2px solid var(--brand); outline-offset: 1px; }
.choices { display: grid; gap: 10px; margin-top: 8px; }
.choice { display: flex; gap: 12px; align-items: center; border: 1px solid var(--line); border-radius: 14px; padding: 14px 16px; cursor: pointer; }
.choice input { width: auto; } .choice b { flex: 1; } .choice span { color: var(--muted); }
.choice:has(input:checked) { border-color: var(--brand); box-shadow: 0 0 0 1px var(--brand); }
.notice { border-radius: 14px; padding: 14px 16px; background: color-mix(in srgb, var(--brand) 10%, transparent); margin-top: 16px; font-size: 15px; }
.notice.warn { background: #fff4e5; color: #8a4b00; } .notice.err { background: #ffe9e9; color: #a40000; }
.keybox { font: 13px/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; word-break: break-all; background: var(--alt); border-radius: 12px; padding: 14px; margin-top: 10px; user-select: all; }
#qr { background: #fff; padding: 12px; border-radius: 14px; display: inline-block; margin-top: 12px; }

/* faq, footer, legal */
details { border-bottom: 1px solid var(--line); padding: 18px 0; } details summary { cursor: pointer; font-weight: 600; font-size: 19px; list-style: none; }
details summary::after { content: "+"; float: right; color: var(--muted); } details[open] summary::after { content: "–"; }
details p { color: var(--muted); margin: 10px 0 0; }
.legal h1 { font-size: 44px; } .legal h2 { font-size: 24px; margin: 34px 0 8px; } .legal p, .legal li { color: var(--muted); }
footer { background: var(--alt); color: var(--muted); font-size: 12px; padding: 34px 0 40px; }
footer .cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 22px; padding-bottom: 22px; border-bottom: 1px solid var(--line); }
footer h4 { color: var(--ink); font-size: 12px; margin: 0 0 8px; font-weight: 600; } footer a { color: var(--muted); display: block; padding: 3px 0; } footer a:hover { color: var(--ink); }
footer .bottom { padding-top: 16px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

/* reveal on scroll */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .8s ease, transform .8s cubic-bezier(.2, .7, .2, 1); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; transition: none; } html { scroll-behavior: auto; } }
@media (max-width: 600px) { br.d { display: none; } }