/* The app's "Hairline" palette (ios/Dialler/App/Theme.swift): near-white
   ground, near-black ink, hairline rules, outlined circles. The only colour
   that is not ink is the end-call red. */
:root {
  --ground: #FBFBFC;
  --ink: #0B0D12;
  --secondary: #5A606C;
  --tertiary: #6B717D;
  --hairline: #ECEEF1;
  --ring: #E2E5EA;
  --fill: #EEF0F3;
  --raised: #FFFFFF;
  --end: #E5484D;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --ground: #0A0B0F;
    --ink: #F4F5F7;
    --secondary: #9AA0AB;
    --tertiary: #7C828E;
    --hairline: #1C1F26;
    --ring: #2A2D36;
    --fill: #16181E;
    --raised: #2A2D36;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --ground: #0A0B0F;
  --ink: #F4F5F7;
  --secondary: #9AA0AB;
  --tertiary: #7C828E;
  --hairline: #1C1F26;
  --ring: #2A2D36;
  --fill: #16181E;
  --raised: #2A2D36;
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 24px; }
@media (max-width: 600px) { .wrap { padding: 0 16px; } }

/* ---- top bar ---- */
header {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--ground) 82%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(20px); backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--hairline);
}
@supports not (background: color-mix(in srgb, red 50%, transparent)) { header { background: var(--ground); } }
section[id] { scroll-margin-top: 60px; }
header .wrap { display: flex; align-items: center; gap: 28px; height: 60px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 500; letter-spacing: -.01em; text-decoration: none; }
.mark { width: 26px; height: 26px; fill: currentColor; display: block; }
nav { display: flex; gap: 24px; margin-left: auto; font-size: 14px; }
nav a { color: var(--secondary); text-decoration: none; }
nav a:hover { color: var(--ink); }
.theme {
  width: 34px; height: 34px; border-radius: 50%;
  border: 1px solid var(--ring); background: transparent; color: var(--ink);
  display: grid; place-items: center; cursor: pointer; padding: 0; flex: none;
}
.theme:hover { background: var(--fill); }
.theme svg { width: 16px; height: 16px; }
.theme .sun { display: none; }
:root[data-theme="dark"] .theme .sun { display: block; }
:root[data-theme="dark"] .theme .moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme .sun { display: block; }
  :root:not([data-theme="light"]) .theme .moon { display: none; }
}
@media (max-width: 720px) { nav { display: none; } .theme { margin-left: auto; } }

/* ---- type ---- */
.label {
  font-size: 11px; font-weight: 500; letter-spacing: .16em; text-transform: uppercase;
  color: var(--secondary); margin: 0 0 20px;
}
h1 {
  font-size: clamp(38px, 5.4vw, 60px); line-height: 1.06; font-weight: 400;
  letter-spacing: -.035em; margin: 0 0 22px;
}
h2 {
  font-size: clamp(28px, 3.6vw, 36px); line-height: 1.12; font-weight: 400;
  letter-spacing: -.03em; margin: 0 0 14px;
}
h3 { font-size: 17px; font-weight: 500; letter-spacing: -.01em; margin: 0 0 4px; }
p { margin: 0 0 12px; }
h1, h2 { text-wrap: balance; }
h1 span { display: block; color: var(--tertiary); }
.meta { font-size: 14px; color: var(--tertiary); margin-top: 22px; }
.lede { font-size: 19px; color: var(--secondary); max-width: 34em; }
.muted { color: var(--secondary); }
code, pre { font: 13.5px/1.6 ui-monospace, "SF Mono", Menlo, Consolas, monospace; }

section { padding: 88px 0; border-top: 1px solid var(--hairline); }
section.hero { border-top: 0; padding: 72px 0 96px; }
.intro { max-width: 36em; margin-bottom: 44px; }
@media (max-width: 600px) { section { padding: 64px 0; } section.hero { padding: 44px 0 64px; } }

/* ---- hero ---- */
.hero .wrap { display: grid; grid-template-columns: 1fr 330px; gap: 56px; align-items: center; }
@media (max-width: 860px) { .hero .wrap { grid-template-columns: minmax(0, 1fr); gap: 56px; } }

/* An iPhone in the app's in-call screen: titanium band, black bezel,
   Dynamic Island. The screen is drawn in the page's colours, so it follows
   the theme; its proportions follow the App Store screenshot (1320 × 2868). */
.iphone {
  position: relative; width: 312px; max-width: 100%; margin: 8px auto; padding: 3px; border-radius: 58px;
  background: linear-gradient(135deg, #e6e7e9 0%, #8e9095 20%, #d8d9dc 46%, #7a7c81 72%, #c7c8cb 100%);
  box-shadow: 0 40px 80px -32px rgba(10, 12, 18, .38), 0 16px 32px -16px rgba(10, 12, 18, .22);
}
.iphone .bezel { padding: 9px; border-radius: 55px; background: #050506; box-shadow: inset 0 0 0 1px #1d1e21; }
.iphone .screen {
  position: relative; overflow: hidden; border-radius: 46px; aspect-ratio: 1320 / 2868;
  background: var(--ground); color: var(--ink);
  display: flex; flex-direction: column; align-items: center; padding: 0 16px 36px;
}
.iphone .screen > * { flex: none; }
.iphone .island { position: absolute; top: 11px; left: 50%; transform: translateX(-50%); width: 88px; height: 26px; border-radius: 13px; background: #000; }
.iphone .status {
  position: absolute; top: 0; left: 0; right: 0; height: 49px; padding: 2px 22px 0 34px;
  display: flex; align-items: center; justify-content: space-between;
  font-size: 14px; font-weight: 600; letter-spacing: -.01em;
}
.iphone .status .icons { display: flex; align-items: center; gap: 5px; }
.iphone .status svg { display: block; fill: currentColor; }
.iphone .home { position: absolute; bottom: 8px; left: 50%; transform: translateX(-50%); width: 104px; height: 4px; border-radius: 2px; background: var(--ink); }
.iphone .btn { position: absolute; width: 3px; border-radius: 2px; background: linear-gradient(90deg, #6d6f74, #cfd0d3); }
.iphone .btn.action { left: -2px; top: 112px; height: 28px; }
.iphone .btn.up { left: -2px; top: 158px; height: 48px; }
.iphone .btn.down { left: -2px; top: 214px; height: 48px; }
.iphone .btn.side { right: -2px; top: 176px; height: 76px; border-radius: 2px; background: linear-gradient(270deg, #6d6f74, #cfd0d3); }
.rings { position: relative; width: 150px; height: 150px; margin-top: 128px; display: grid; place-items: center; }
.rings i {
  position: absolute; inset: 0; border: 1px solid var(--ink); border-radius: 50%;
  opacity: 0; transform: scale(.34);
  animation: pulse 4.2s linear infinite;
}
.rings i:nth-child(2) { animation-delay: -1.4s; }
.rings i:nth-child(3) { animation-delay: -2.8s; }
@keyframes pulse {
  0% { transform: scale(.46); opacity: 0; }
  12% { opacity: .26; }
  100% { transform: scale(1); opacity: 0; }
}
@media (prefers-reduced-motion: reduce) {
  .rings i { animation: none; }
  .rings i:nth-child(1) { transform: scale(.6); opacity: .14; }
  .rings i:nth-child(2) { transform: scale(.8); opacity: .09; }
  .rings i:nth-child(3) { transform: scale(1); opacity: .05; }
}
.monogram {
  position: relative; width: 68px; height: 68px; border-radius: 50%;
  border: 1.25px solid var(--ink); display: grid; place-items: center;
  font-size: 23px; letter-spacing: .01em;
}
.iphone .who { font-size: 25px; letter-spacing: -.03em; margin: 22px 0 0; }
.iphone .time { color: var(--secondary); font-size: 15px; font-variant-numeric: tabular-nums; }
.controls { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-top: auto; width: 100%; }
.controls div { display: flex; flex-direction: column; align-items: center; gap: 7px; font-size: 10px; color: var(--secondary); }
.controls span {
  width: 48px; height: 48px; border-radius: 50%; border: 1px solid var(--ring);
  display: grid; place-items: center; color: var(--ink);
}
.controls svg, .end svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.end { width: 56px; height: 56px; border-radius: 50%; background: var(--end); color: #fff; display: grid; place-items: center; margin-top: 26px; flex: none; }
.end svg { width: 24px; height: 24px; fill: currentColor; stroke: none; }

/* ---- spec lists ---- */
table.spec td:first-child { width: 200px; color: var(--ink); }
table.spec tr:last-child td { border-bottom: 1px solid var(--hairline); }
@media (max-width: 600px) {
  table.spec tr { display: block; padding: 12px 0; border-top: 1px solid var(--hairline); }
  table.spec td { display: block; width: auto; padding: 0; border: 0; }
  table.spec td:first-child { width: auto; font-weight: 500; }
  table.spec tr:last-child { border-bottom: 1px solid var(--hairline); }
  table.spec tr:last-child td { border-bottom: 0; }
}
.note { margin-top: 44px; color: var(--secondary); }

/* ---- how it works ---- */
.diagram { display: grid; grid-template-columns: 1fr 1.1fr 1fr 1.1fr 1fr; align-items: start; margin: 8px 0 56px; }
.node { text-align: center; }
.node .circle {
  width: 84px; height: 84px; border-radius: 50%; border: 1px solid var(--ring);
  display: grid; place-items: center; margin: 0 auto 14px;
}
.node.core .circle { border: 1.25px solid var(--ink); }
.node .circle svg { width: 30px; height: 30px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; stroke-linejoin: round; }
.node .circle svg.mark { width: 34px; height: 34px; fill: currentColor; stroke: none; }
.node h3 { font-size: 15px; }
.node p { font-size: 13px; color: var(--secondary); margin: 0; }
.link { position: relative; height: 84px; padding-top: 8px; text-align: center; font-size: 12px; line-height: 1.4; color: var(--secondary); }
.link::after { content: ""; position: absolute; left: 4px; right: 4px; top: 42px; border-top: 1px solid var(--ink); }
.link b { display: block; font-weight: 500; color: var(--ink); font-size: 12px; }
@media (max-width: 760px) {
  .diagram { grid-template-columns: 1fr; gap: 0; max-width: 320px; margin-left: auto; margin-right: auto; }
  .link { height: auto; min-height: 72px; padding: 18px 0 18px 58%; margin: 8px 0; text-align: left; }
  .link::after { left: 50%; right: auto; top: 0; bottom: 0; border-top: 0; border-left: 1px solid var(--ink); }
}

.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; counter-reset: step; }
.steps li { counter-increment: step; }
.steps li::before {
  content: counter(step); display: grid; place-items: center;
  width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--ring);
  font-size: 13px; margin-bottom: 16px;
}
.steps p { color: var(--secondary); margin: 0; }
@media (max-width: 760px) { .steps { grid-template-columns: 1fr; gap: 28px; } }

/* ---- set-up ---- */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.split > * { min-width: 0; }
@media (max-width: 860px) { .split { grid-template-columns: 1fr; gap: 36px; } }
pre {
  margin: 0 0 14px; padding: 18px 20px; background: var(--fill); border-radius: 12px;
  overflow-x: auto; color: var(--ink);
}
pre .c { color: var(--tertiary); }
.caption { font-size: 13px; color: var(--secondary); margin: -4px 0 22px; }
table { width: 100%; border-collapse: collapse; font-size: 15px; }
td { padding: 11px 0; border-top: 1px solid var(--hairline); vertical-align: top; }
td:first-child { width: 42%; font-variant-numeric: tabular-nums; }
td code { font-size: 14px; }
td + td { color: var(--secondary); }
td a { color: var(--ink); text-decoration: underline; text-decoration-color: var(--ring); text-underline-offset: 3px; }
td a:hover { text-decoration-color: var(--ink); }


footer { border-top: 1px solid var(--hairline); padding: 28px 0 40px; font-size: 13px; color: var(--secondary); }
footer .wrap { display: flex; align-items: center; gap: 10px; }
footer .mark { width: 18px; height: 18px; }
footer .right { margin-left: auto; display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 6px 22px; }
footer a { color: var(--secondary); text-decoration: none; }
footer a:hover { color: var(--ink); }
@media (max-width: 600px) { footer .wrap { flex-wrap: wrap; } footer .right { margin-left: 0; width: 100%; justify-content: flex-start; } }

/* ---- privacy policy ---- */
.policy { padding-top: 72px; padding-bottom: 96px; }
.policy h1 { font-size: clamp(34px, 4.6vw, 48px); margin-bottom: 10px; }
.policy .updated { color: var(--tertiary); font-size: 14px; margin-bottom: 44px; }
.policy h2 { font-size: 22px; letter-spacing: -.02em; margin: 52px 0 14px; scroll-margin-top: 76px; }
.policy h3 { font-size: 16px; margin: 28px 0 8px; }
.policy p, .policy li { color: var(--secondary); }
.policy strong { color: var(--ink); font-weight: 500; }
.policy ul { margin: 0 0 14px; padding-left: 20px; }
.policy li { margin-bottom: 6px; }
.policy li::marker { color: var(--tertiary); }
.policy a { color: var(--ink); text-decoration: underline; text-decoration-color: var(--ring); text-underline-offset: 3px; }
.policy a:hover { text-decoration-color: var(--ink); }
.policy address { font-style: normal; color: var(--secondary); margin-bottom: 12px; }
@media (max-width: 600px) { .policy { padding-top: 44px; padding-bottom: 64px; } }