/* altffour.com — the app's Glass Keycap look: frosted glass panels, raised
   keycap buttons that sink when pressed, glowing LED type, cyan accent.
   Values follow apps/native/src/redesign/tokens.ts and ui/fx.ts. */

@font-face { font-family: "Chakra Petch"; src: url("fonts/ChakraPetch-500.woff2") format("woff2"); font-weight: 500; font-display: swap; }
@font-face { font-family: "Chakra Petch"; src: url("fonts/ChakraPetch-600.woff2") format("woff2"); font-weight: 600; font-display: swap; }
@font-face { font-family: "Chakra Petch"; src: url("fonts/ChakraPetch-700.woff2") format("woff2"); font-weight: 700; font-display: swap; }
@font-face { font-family: "JetBrains Mono"; src: url("fonts/JetBrainsMono.woff2") format("woff2"); font-weight: 500 700; font-display: swap; }

:root {
  color-scheme: dark;
  --bg: #0b0d12;
  --bg-raised: #10131a;
  --text: #eef2f7;
  --soft: #d6dce6;
  --muted: #aab3c1;
  --faint: #8a93a3;
  --line: rgba(255, 255, 255, 0.14);
  --line-strong: rgba(255, 255, 255, 0.2);
  --glass: rgba(16, 19, 26, 0.55);
  --glass-strong: rgba(16, 19, 26, 0.78);
  --well: rgba(6, 8, 12, 0.55);
  --accent: #00d2ff;
  --accent-deep: #007f9c;
  --accent-text: #00d2ff;
  --on-accent: #03151b;
  --glow: rgba(0, 210, 255, 0.28);
  --key-bg: rgba(22, 26, 34, 0.42);
  --key-fill: linear-gradient(180deg, rgba(255, 255, 255, 0.16), rgba(255, 255, 255, 0.06));
  --key-wall: #05070a;
  --key-sheen: rgba(255, 255, 255, 0.2);
  --aurora-a: rgba(0, 210, 255, 0.2);
  --aurora-b: rgba(157, 80, 187, 0.2);
  --aurora-c: rgba(57, 255, 159, 0.07);
  --shot-shadow: 0 30px 90px rgba(0, 0, 0, 0.55), 0 0 0 1px rgba(255, 255, 255, 0.08);
  --display: "Chakra Petch", ui-sans-serif, system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --radius: 22px;
  --page: 1180px;
  --gutter: 16px;
}

@media (prefers-color-scheme: light) {
  :root {
    color-scheme: light;
    --bg: #eef1f6;
    --bg-raised: #ffffff;
    --text: #0d1117;
    --soft: #1f2733;
    --muted: #4a5565;
    --faint: #5f6b7c;
    --line: rgba(13, 23, 40, 0.12);
    --line-strong: rgba(13, 23, 40, 0.2);
    --glass: rgba(255, 255, 255, 0.66);
    --glass-strong: rgba(255, 255, 255, 0.86);
    --well: rgba(13, 23, 40, 0.05);
    --accent: #00c2ec;
    --accent-deep: #0086a6;
    --accent-text: #006f8c;
    --on-accent: #03151b;
    --glow: rgba(0, 170, 210, 0.25);
    --key-bg: rgba(255, 255, 255, 0.8);
    --key-fill: linear-gradient(180deg, #ffffff, #eef1f5);
    --key-wall: #c4ccd7;
    --key-sheen: rgba(255, 255, 255, 0.9);
    --aurora-a: rgba(0, 194, 236, 0.18);
    --aurora-b: rgba(157, 80, 187, 0.12);
    --aurora-c: rgba(0, 200, 140, 0.06);
    --shot-shadow: 0 24px 70px rgba(13, 23, 40, 0.22), 0 0 0 1px rgba(13, 23, 40, 0.08);
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition: none !important; animation: none !important; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 500 17px/1.6 var(--display);
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent-text); text-underline-offset: 3px; }
h1, h2, h3 { font-weight: 700; line-height: 1.12; letter-spacing: -0.01em; margin: 0; }
p { margin: 0 0 14px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }

.skip { position: absolute; left: -9999px; top: 8px; z-index: 100; }
.skip:focus { left: 16px; }

/* The glow behind everything. */
.aurora { position: fixed; inset: -20vh -10vw auto; height: 120vh; z-index: -1; pointer-events: none;
  background:
    radial-gradient(40vw 34vh at 18% 12%, var(--aurora-a), transparent 70%),
    radial-gradient(38vw 36vh at 84% 6%, var(--aurora-b), transparent 70%),
    radial-gradient(50vw 30vh at 60% 60%, var(--aurora-c), transparent 70%);
  filter: blur(10px); }

.wrap { max-width: var(--page); margin: 0 auto; padding: 0 var(--gutter); }

/* ---------- Building blocks ---------- */

.glass {
  background: var(--glass);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  -webkit-backdrop-filter: blur(26px) saturate(1.2);
  backdrop-filter: blur(26px) saturate(1.2);
}

.key {
  --wall: 5px;
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 50px; padding: 0 22px; border-radius: 13px;
  font: 600 17px/1 var(--display); color: var(--text); text-decoration: none; white-space: nowrap;
  border: 1px solid var(--line-strong);
  background: var(--key-fill), var(--key-bg);
  box-shadow: 0 var(--wall) 0 var(--key-wall), inset 0 1px 0 var(--key-sheen);
  -webkit-backdrop-filter: blur(16px); backdrop-filter: blur(16px);
  transition: transform 90ms ease, box-shadow 90ms ease, filter 120ms ease;
  cursor: pointer; user-select: none; margin-bottom: var(--wall);
}
.key:hover { filter: brightness(1.12); }
.key:active { transform: translateY(calc(var(--wall) - 1px)); box-shadow: 0 1px 0 var(--key-wall), inset 0 1px 0 var(--key-sheen); }
.key svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.key-lit {
  background: var(--accent); color: var(--on-accent); border-color: transparent;
  box-shadow: 0 var(--wall) 0 var(--accent-deep), inset 0 1px 0 rgba(255, 255, 255, 0.5), 0 0 22px var(--glow);
}
.key-lit:active { box-shadow: 0 1px 0 var(--accent-deep), inset 0 1px 0 rgba(255, 255, 255, 0.5), 0 0 26px var(--glow); }
.key-sm { --wall: 4px; min-height: 40px; padding: 0 15px; font-size: 15px; border-radius: 11px; }

.led { font: 700 13px/1.3 var(--mono); letter-spacing: 0.14em; text-transform: uppercase; color: var(--accent-text); text-shadow: 0 0 12px var(--glow); }
.led-dot::before { content: ""; display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); margin-right: 10px; vertical-align: 1px; }

.chip { display: inline-flex; align-items: center; gap: 6px; padding: 5px 10px; border-radius: 9px; border: 1px solid var(--line-strong); background: var(--well); font: 700 12px/1.2 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--soft); }
.chip-accent { color: var(--accent-text); border-color: color-mix(in srgb, var(--accent) 45%, transparent); }

.icon { width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center; background: var(--well); border: 1px solid var(--line); color: var(--accent-text); flex: none; }
.icon svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

/* ---------- Header ---------- */

.top { position: sticky; top: 0; z-index: 50; padding: 12px var(--gutter) 0; }
.top-inner {
  max-width: var(--page); margin: 0 auto; display: flex; align-items: center; gap: 18px;
  padding: 10px 12px 10px 18px; border-radius: 18px;
  background: var(--glass-strong); border: 1px solid var(--line);
  -webkit-backdrop-filter: blur(26px) saturate(1.2); backdrop-filter: blur(26px) saturate(1.2);
}
.brand img { height: 42px; width: auto; }
.nav { display: flex; gap: 4px; margin-left: 10px; }
.nav a, .menu-panel a:not(.key) { color: var(--soft); text-decoration: none; font-weight: 600; padding: 8px 12px; border-radius: 10px; }
.nav a:hover, .menu-panel a:not(.key):hover { background: var(--well); color: var(--text); }
.nav a[aria-current="page"], .menu-panel a[aria-current="page"] { color: var(--accent-text); }
.top-actions { margin-left: auto; display: flex; gap: 10px; align-items: center; }
.top-actions .key { margin-bottom: 4px; }
.menu { display: none; margin-left: auto; position: relative; }
.menu summary { list-style: none; padding: 0 11px; }
.menu summary::-webkit-details-marker { display: none; }
.menu-panel { position: absolute; right: 0; top: calc(100% + 10px); width: min(280px, calc(100vw - 32px)); display: flex; flex-direction: column; gap: 4px; padding: 12px; background: var(--glass-strong); }
.menu-panel .key { margin-top: 8px; }

@media (max-width: 860px) {
  .nav, .top-actions { display: none; }
  .menu { display: block; }
  .brand img { height: 36px; }
}

/* ---------- Sections ---------- */

section { padding: 72px 0; }
.section-head { max-width: 760px; margin-bottom: 36px; }
.section-head h2 { font-size: clamp(30px, 4.2vw, 44px); margin: 10px 0 14px; }
.section-head p { color: var(--muted); font-size: 19px; }
.center { text-align: center; margin-left: auto; margin-right: auto; }

/* Hero */
.hero { padding: 64px 0 40px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.25fr); gap: 48px; align-items: center; }
.hero h1 { font-size: clamp(40px, 6vw, 68px); margin: 16px 0 18px; }
.hero h1 em { font-style: normal; color: var(--accent-text); text-shadow: 0 0 28px var(--glow); }
.hero .lede { font-size: 20px; color: var(--muted); max-width: 560px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 26px 0 18px; }
.stores { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; color: var(--faint); font-size: 15px; }
.store { display: inline-flex; align-items: center; gap: 10px; padding: 9px 14px; border-radius: 12px; border: 1px solid var(--line); background: var(--well); color: var(--soft); font-weight: 600; font-size: 15px; }
a.store { text-decoration: none; }
a.store:hover { border-color: color-mix(in srgb, var(--accent) 45%, transparent); color: var(--text); }
.store svg { width: 20px; height: 20px; fill: currentColor; }
.store .soon { font: 700 10px/1 var(--mono); letter-spacing: 0.12em; color: var(--accent-text); border: 1px solid color-mix(in srgb, var(--accent) 45%, transparent); padding: 3px 6px; border-radius: 6px; }

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero { padding-top: 40px; }
}

/* Screenshots: the app's own frame (dark glass edge), click to enlarge. */
.shot { position: relative; border-radius: 18px; overflow: hidden; box-shadow: var(--shot-shadow); background: #0b0d12; }
.shot img { width: 100%; cursor: zoom-in; }
.shot-phone { border-radius: 30px; border: 6px solid #12151c; box-shadow: var(--shot-shadow); max-width: 300px; }
.shot-pending { aspect-ratio: 16 / 10; display: grid; place-items: center; color: var(--faint); font: 600 14px var(--mono); }
.shot-phone.shot-pending { aspect-ratio: 390 / 844; }
.hero-shot { position: relative; }
.hero-shot .shot-phone { position: absolute; right: -10px; bottom: -40px; width: 30%; min-width: 120px; }
@media (max-width: 900px) { .hero-shot .shot-phone { right: 8px; bottom: -28px; } }
.caption { color: var(--faint); font-size: 14px; margin-top: 12px; }

/* Feature cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; }
.card { padding: 24px; display: flex; flex-direction: column; gap: 12px; }
.card h3 { font-size: 21px; }
.card p { color: var(--muted); margin: 0; }
.card .stock { margin-top: auto; padding-top: 12px; border-top: 1px dashed var(--line); font: 500 13px/1.5 var(--mono); color: var(--faint); }
.card .stock b { color: var(--soft); font-weight: 700; }

/* Alternating feature rows with a big screenshot */
.feature { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr); gap: 48px; align-items: center; padding: 40px 0; }
.feature:nth-of-type(even) .feature-text { order: 2; }
.feature h3 { font-size: clamp(26px, 3.2vw, 36px); margin: 10px 0 14px; }
.feature p { color: var(--muted); font-size: 18px; }
.ticks { list-style: none; padding: 0; margin: 16px 0 0; display: grid; gap: 10px; }
.ticks li { position: relative; padding-left: 30px; color: var(--soft); }
.ticks li::before { content: ""; position: absolute; left: 0; top: 0.42em; width: 16px; height: 16px; border-radius: 5px; background: var(--accent); box-shadow: 0 0 10px var(--glow); -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='M3 8.5l3.2 3L13 4.5' fill='none' stroke='black' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / contain no-repeat; mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='M3 8.5l3.2 3L13 4.5' fill='none' stroke='black' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / contain no-repeat; }
@media (max-width: 900px) {
  .feature { grid-template-columns: 1fr; gap: 24px; }
  .feature:nth-of-type(even) .feature-text { order: 0; }
}

.phones { display: flex; gap: 22px; justify-content: center; flex-wrap: wrap; }
.phones .shot-phone { width: 250px; }

/* Comparison table */
.compare-wrap { overflow-x: auto; border-radius: var(--radius); }
.compare { width: 100%; border-collapse: collapse; min-width: 620px; }
.compare th, .compare td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--line); vertical-align: top; }
.compare thead th { font: 700 13px var(--mono); letter-spacing: 0.1em; text-transform: uppercase; color: var(--faint); }
.compare tbody th { font-weight: 600; color: var(--text); width: 30%; }
.compare td { color: var(--muted); }
.compare td.yes { color: var(--soft); }
.compare td.yes::before { content: "● "; color: var(--accent); text-shadow: 0 0 8px var(--glow); }
.compare tr:last-child th, .compare tr:last-child td { border-bottom: 0; }

/* Feature groups on the Features page */
.group { padding: 56px 0; border-top: 1px solid var(--line); }
.group:first-of-type { border-top: 0; }
.group-head { display: flex; gap: 18px; align-items: flex-start; margin-bottom: 26px; }
.group-head h2 { font-size: clamp(28px, 3.6vw, 38px); margin-bottom: 8px; }
.group-head p { color: var(--muted); margin: 0; font-size: 18px; max-width: 720px; }
.group-body { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr); gap: 36px; align-items: start; }
.group-body.no-shot { grid-template-columns: 1fr; }
.list { display: grid; gap: 12px; }
.item { padding: 16px 18px; }
.item h3 { font-size: 18px; margin-bottom: 6px; }
.item p { color: var(--muted); margin: 0; font-size: 16px; }
.item .vs { display: block; margin-top: 8px; font: 500 13px/1.5 var(--mono); color: var(--faint); }
.shots { display: grid; gap: 16px; position: sticky; top: 100px; }
@media (max-width: 900px) { .group-body { grid-template-columns: 1fr; } .shots { position: static; } }

.toc { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }

/* Band */
.band { padding: 40px; display: grid; grid-template-columns: minmax(0, 1.4fr) auto; gap: 30px; align-items: center; }
.band h2 { font-size: clamp(26px, 3.4vw, 36px); margin-bottom: 10px; }
.band p { color: var(--muted); margin: 0; }
@media (max-width: 760px) { .band { grid-template-columns: 1fr; padding: 28px; } }

/* FAQ */
.faq { display: grid; gap: 12px; max-width: 860px; }
.faq details { padding: 4px 22px; }
.faq summary { cursor: pointer; padding: 16px 0; font-weight: 700; font-size: 18px; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--mono); color: var(--accent-text); }
.faq details[open] summary::after { content: "–"; }
.faq details p { color: var(--muted); }

/* Steps */
.steps { counter-reset: step; display: grid; gap: 14px; padding: 0; margin: 0; list-style: none; }
.steps li { counter-increment: step; position: relative; padding: 18px 20px 18px 70px; }
.steps li::before { content: counter(step, decimal-leading-zero); position: absolute; left: 20px; top: 16px; font: 700 20px var(--mono); color: var(--accent-text); text-shadow: 0 0 12px var(--glow); }
.copy-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-top: 10px; }
.copy-row code { flex: 1 1 260px; }

/* The APK's facts on the download page */
.facts { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: 8px 18px; margin: 16px 0 0; }
.facts dt { color: var(--faint); font: 600 13px/1.9 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; }
.facts dd { margin: 0; color: var(--soft); }
.facts dd code { padding: 2px 7px; font-size: 14px; }
@media (max-width: 600px) { .facts { grid-template-columns: 1fr; } .facts dd { margin-bottom: 8px; } }
code { font: 500 15px var(--mono); background: var(--well); border: 1px solid var(--line); border-radius: 9px; padding: 9px 12px; word-break: break-all; color: var(--soft); }
p code, li code { padding: 2px 7px; font-size: 14px; }

/* Page header for inner pages */
.page-head { padding: 64px 0 24px; }
.page-head h1 { font-size: clamp(38px, 5.4vw, 60px); margin: 14px 0 16px; }
.page-head p { color: var(--muted); font-size: 20px; max-width: 760px; }

/* Long text (legal pages) */
.prose { max-width: 780px; padding: 32px 36px; margin-bottom: 72px; }
.prose h2 { font-size: 24px; margin: 30px 0 10px; }
.prose h2:first-child { margin-top: 0; }
.prose p, .prose li { color: var(--soft); }
.prose ul { padding-left: 22px; margin: 0 0 14px; }
.prose li { margin: 6px 0; }
.prose .updated { color: var(--faint); font: 500 14px var(--mono); }
@media (max-width: 600px) { .prose { padding: 24px 20px; } }

/* Footer */
.foot { margin-top: 40px; border-top: 1px solid var(--line); background: color-mix(in srgb, var(--bg) 70%, transparent); }
.foot-inner { max-width: var(--page); margin: 0 auto; padding: 48px var(--gutter) 24px; display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 40px; }
.foot-brand img { height: 36px; width: auto; margin-bottom: 14px; }
.foot-brand p { color: var(--muted); max-width: 320px; }
.foot-links { display: grid; grid-template-columns: repeat(3, minmax(120px, auto)); gap: 32px; }
.foot-links h2 { font: 700 12px var(--mono); letter-spacing: 0.14em; text-transform: uppercase; color: var(--faint); margin-bottom: 12px; }
.foot-links a { display: block; color: var(--soft); text-decoration: none; padding: 4px 0; }
.foot-links a:hover { color: var(--accent-text); }
.foot-legal { max-width: var(--page); margin: 0 auto 14px; padding: 16px var(--gutter) 0; color: var(--muted); font-size: 14px; border-top: 1px solid var(--line); }
.foot-legal strong { color: var(--text); }
.foot-note { max-width: var(--page); margin: 0 auto; padding: 0 var(--gutter) 36px; color: var(--faint); font-size: 14px; }
@media (max-width: 760px) { .foot-inner { grid-template-columns: 1fr; } .foot-links { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

/* Lightbox */
.lightbox { border: 0; padding: 0; background: transparent; max-width: min(1400px, 96vw); max-height: 94vh; }
.lightbox::backdrop { background: rgba(5, 7, 10, 0.86); -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px); }
.lightbox img { max-height: 90vh; width: auto; border-radius: 14px; margin: 0 auto; }
.lightbox form { position: absolute; top: 10px; right: 10px; }

/* LED labels keep their look inside blocks that style their own paragraphs. */
.section-head .led, .page-head .led, .feature .led, .band .led, .group-head .led { color: var(--accent-text); font-size: 13px; margin-bottom: 0; }

/* Yes / partly / no marks in the comparison table */
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.compare-marks td { white-space: nowrap; }
.compare-marks td.note { white-space: normal; font-size: 15px; color: var(--faint); }
.compare-marks tbody th { width: auto; }
.mark { display: inline-grid; place-items: center; width: 28px; height: 28px; border-radius: 8px; font: 700 15px/1 var(--mono); }
.mark-yes { background: var(--accent); color: var(--on-accent); box-shadow: 0 0 12px var(--glow); }
.mark-part { border: 1px solid var(--line-strong); color: var(--soft); background: var(--well); }
.mark-no { border: 1px dashed var(--line-strong); color: var(--faint); }
.compact-compare .note { display: none; }
.compact-compare .compare { min-width: 0; }
@media (max-width: 640px) { .compare-marks .note { display: none; } .compare { min-width: 0; } .compare th, .compare td { padding: 12px 10px; } }
.mark-part::before { content: ""; width: 12px; height: 12px; border-radius: 50%; border: 2px solid currentColor; background: linear-gradient(90deg, currentColor 50%, transparent 50%); }
.marks-key .mark { width: 20px; height: 20px; font-size: 12px; vertical-align: -4px; margin: 0 2px 0 8px; }
.marks-key .mark:first-child { margin-left: 0; }
.marks-key .mark-part::before { width: 9px; height: 9px; }