:root {
  --bg: #ffffff;
  --ink: #111111;
  --mute: #6f6f6f;
  --faint: #a8a8a8;
  --rule: #ececec;
  --soft: #f6f6f4;
  --serif: 'Instrument Serif', Georgia, serif;
  --sans: 'Geist', system-ui, -apple-system, sans-serif;
  --mono: 'Geist Mono', ui-monospace, Menlo, monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 16px/1.6 var(--sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; }
b { font-weight: 500; }
.mono { font-family: var(--mono); font-feature-settings: 'tnum'; letter-spacing: -0.01em; }
.serif { font-family: var(--serif); font-weight: 400; }
.wrap { width: 100%; max-width: 1040px; margin: 0 auto; padding: 0 24px; }

/* header */
.top { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.mark { font: 400 26px/1 var(--serif); text-decoration: none; letter-spacing: 0.02em; }
nav { display: flex; gap: 28px; align-items: center; font-size: 14px; }
nav a { text-decoration: none; color: var(--mute); transition: color .15s; }
nav a:hover { color: var(--ink); }
nav .buy { color: var(--ink); border: 1px solid var(--ink); padding: 7px 14px; border-radius: 999px; }
nav .buy:hover { background: var(--ink); color: var(--bg); }

/* hero */
.hero { padding-top: 72px; padding-bottom: 96px; }
.eyebrow { display: flex; align-items: center; gap: 10px; color: var(--mute); font-size: 14px; margin: 0 0 28px; }
.dot { width: 7px; height: 7px; border-radius: 50%; background: var(--ink); animation: breathe 2.4s ease-in-out infinite; }
@keyframes breathe { 0%, 100% { opacity: 1; } 50% { opacity: .15; } }
h1 {
  font: 400 clamp(46px, 8vw, 100px)/1 var(--serif);
  letter-spacing: -0.02em;
  margin: 0 0 36px;
}
.lede { max-width: 580px; font-size: 18px; color: #333; margin: 0 0 18px; }
.lede:last-of-type { margin-bottom: 56px; }

.clock { display: flex; gap: 72px; padding: 28px 0; border-top: 1px solid var(--ink); border-bottom: 1px solid var(--rule); margin-bottom: 28px; flex-wrap: wrap; }
.clock > div { display: flex; flex-direction: column; gap: 6px; }
.label { font-size: 12px; color: var(--mute); text-transform: uppercase; letter-spacing: .08em; }
.big { font-size: clamp(36px, 5vw, 52px); line-height: 1; font-weight: 400; }
.sub { font-size: 13px; color: var(--mute); }

.ca {
  display: inline-flex; align-items: center; gap: 14px; max-width: 100%;
  background: var(--soft); border: 1px solid var(--rule); border-radius: 10px;
  padding: 12px 16px; font-size: 14px; color: var(--ink); cursor: pointer;
}
.ca:hover { border-color: var(--faint); }
.ca .label { margin: 0; }
#ca-text { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.copy { color: var(--mute); font-size: 12px; }

/* sections */
section { scroll-margin-top: 24px; }
.kicker {
  font: 500 12px/1 var(--sans); text-transform: uppercase; letter-spacing: .1em; color: var(--mute);
  margin: 0 0 40px; padding-top: 20px; border-top: 1px solid var(--rule);
}
.math, .how, .live, .check { padding-bottom: 120px; }

.facts { display: grid; grid-template-columns: repeat(3, 1fr); gap: 48px; margin-bottom: 72px; }
.fact .num { display: block; font-size: clamp(48px, 6vw, 72px); line-height: 1; margin-bottom: 16px; letter-spacing: -0.02em; }
.fact p { margin: 0; color: #444; font-size: 15px; max-width: 290px; }
.src { display: block; margin-top: 10px; font-size: 12px; color: var(--faint); text-decoration: none; }
a.src:hover { color: var(--ink); }

.day { margin: 0; }
.grid { display: grid; grid-template-columns: repeat(60, 1fr); gap: 3px; max-width: 660px; }
.grid i { display: block; aspect-ratio: 1; border-radius: 50%; background: #e4e4e1; }
.grid i.on { background: var(--ink); animation: breathe 2.4s ease-in-out infinite; }
.grid i.past { background: #cfcfcb; }
.day figcaption { margin-top: 28px; max-width: 560px; color: #444; font-size: 17px; }
.day figcaption b { display: block; margin-top: 8px; font: 400 32px/1.15 var(--serif); color: var(--ink); }

.steps { list-style: none; margin: 0; padding: 0; }
.steps li { display: grid; grid-template-columns: 80px 1fr; padding: 28px 0; border-bottom: 1px solid var(--rule); }
.steps li:first-child { padding-top: 0; }
.steps .n { color: var(--faint); font-size: 14px; padding-top: 6px; }
.steps h3 { font: 400 30px/1.15 var(--serif); margin: 0 0 8px; }
.steps p { margin: 0; color: #444; max-width: 620px; }
.fine { color: var(--mute); font-size: 13px; max-width: 620px; margin: 28px 0 0 80px; }

.rules { padding-bottom: 120px; }
.rulelist { margin: 0; border-top: 1px solid var(--ink); }
.rulelist > div { display: grid; grid-template-columns: 240px 1fr; gap: 24px; padding: 18px 0; border-bottom: 1px solid var(--rule); }
.rulelist dt { color: var(--mute); font-size: 14px; }
.rulelist dd { margin: 0; color: #222; max-width: 640px; }
.addr { text-decoration: none; word-break: break-all; font-size: 14px; border-bottom: 1px solid var(--rule); }
.addr:hover { border-color: var(--ink); }

.hint { color: var(--faint); font-weight: 400; }
.tbl tr.pick { cursor: pointer; }
.tbl tr.pick:hover td { background: var(--soft); }
.tbl tr.sel td { background: var(--soft); }
.round { margin-top: 48px; }
.round .headline { font: 400 28px/1.2 var(--serif); margin: 0 0 6px; }
.round .meta { color: var(--mute); font-size: 14px; margin: 0 0 20px; }
.round .scroll { max-height: 560px; overflow: auto; border-bottom: 1px solid var(--rule); }
.txs-h { margin-top: 64px; }

.stats { display: grid; grid-template-columns: repeat(5, 1fr); border-top: 1px solid var(--ink); margin-bottom: 64px; }
.stats > div { padding: 22px 20px 22px 0; display: flex; flex-direction: column; gap: 10px; border-bottom: 1px solid var(--rule); }
.stats > div + div { padding-left: 20px; border-left: 1px solid var(--rule); }
.val { font-size: 26px; line-height: 1.1; }

.cols { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; }
.small { font: 500 14px/1 var(--sans); margin: 0 0 16px; }
.tbl { width: 100%; border-collapse: collapse; font-size: 14px; }
.tbl th { text-align: left; font-weight: 400; color: var(--mute); font-size: 12px; padding: 0 0 10px; border-bottom: 1px solid var(--ink); }
.tbl td { padding: 11px 0; border-bottom: 1px solid var(--rule); font-family: var(--mono); font-size: 13px; }
.tbl .r { text-align: right; }
.tbl td.empty { font-family: var(--sans); color: var(--faint); }
.tbl a { text-decoration: none; border-bottom: 1px solid var(--rule); }
.tbl a:hover { border-color: var(--ink); }

#check-form { display: flex; gap: 10px; max-width: 640px; }
#check-input {
  flex: 1; min-width: 0; font-size: 15px; padding: 14px 16px; border: 1px solid var(--rule); border-radius: 10px;
  background: var(--bg); color: var(--ink); outline: none;
}
#check-input:focus { border-color: var(--ink); }
#check-form button {
  font: 500 15px var(--sans); padding: 0 24px; border-radius: 10px; border: 1px solid var(--ink);
  background: var(--ink); color: var(--bg); cursor: pointer;
}
.result { max-width: 640px; margin-top: 28px; }
.result .headline { font: 400 32px/1.2 var(--serif); margin: 0 0 20px; }
.result dl { display: grid; grid-template-columns: 1fr 1fr; margin: 0; border-top: 1px solid var(--ink); }
.result dl > div { padding: 14px 0; border-bottom: 1px solid var(--rule); }
.result dt { font-size: 12px; color: var(--mute); text-transform: uppercase; letter-spacing: .08em; margin-bottom: 4px; }
.result dd { margin: 0; font-family: var(--mono); font-size: 16px; }
.result .err { color: var(--mute); }

.foot { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding-top: 28px; padding-bottom: 48px; border-top: 1px solid var(--rule); font-size: 13px; color: var(--mute); }
.foot a { text-decoration: none; word-break: break-all; }
.foot a:hover { color: var(--ink); }

@media (max-width: 820px) {
  .facts { grid-template-columns: 1fr; gap: 40px; }
  .stats { grid-template-columns: 1fr 1fr; }
  .stats > div:nth-child(3) { padding-left: 0; border-left: 0; }
  .cols { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .wrap { padding: 0 16px; }
  nav { gap: 16px; }
  nav a:not(.buy) { display: none; }
  .hero { padding-top: 40px; padding-bottom: 72px; }
  .lede { font-size: 16px; }
  .clock { gap: 32px; }
  .grid { gap: 2px; }
  .steps li { grid-template-columns: 44px 1fr; }
  .steps h3 { font-size: 25px; }
  .rulelist > div { grid-template-columns: 1fr; gap: 4px; }
  .rules { padding-bottom: 88px; }
  .val { font-size: 21px; }
  .math, .how, .live, .check { padding-bottom: 88px; }
  .result dl { grid-template-columns: 1fr; }
}