:root {
  --paper: #f4f1e8;
  --line: #c9d4e8;
  --navy: #1c3a6e;
  --navy-2: #2a4a82;
  --brass: #b08a4a;
  --ink: #1a2430;
  --mute: #5a6570;
  --ok: #2d6a4f;
  --warn: #a45c2a;
  --serif: "Noto Serif SC", "Songti SC", serif;
  --sans: "Noto Sans SC", "PingFang SC", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, monospace;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

section[id] {
  scroll-margin-top: 80px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

.app-link {
  color: var(--navy);
  text-decoration: underline;
  text-underline-offset: 3px;
}

button {
  font-family: inherit;
  cursor: pointer;
}

code {
  font-family: var(--mono);
  background: rgba(28, 58, 110, 0.08);
  padding: 0.05em 0.35em;
}

.grid-paper {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 1;
  opacity: 0.35;
  background-image: url("images/texture.webp");
  background-size: 280px auto;
}

.skip {
  position: absolute;
  left: -999px;
}

.skip:focus {
  left: 12px;
  top: 10px;
  z-index: 70;
  background: var(--navy);
  color: #fff;
  padding: 8px 12px;
}

.box-bar {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 24px;
  background: rgba(244, 241, 232, 0.94);
  border-bottom: 2px solid var(--navy);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--serif);
  font-weight: 700;
}

.brand small {
  display: block;
  font-family: var(--mono);
  font-weight: 400;
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--mute);
}

.key {
  width: 34px;
  height: 28px;
  border: 2px solid var(--navy);
  color: var(--navy);
  display: grid;
  place-items: center;
  font-size: 13px;
  background: #fff;
}

.nav-toggle {
  display: none;
  background: #fff;
  border: 2px solid var(--navy);
  color: var(--navy);
  padding: 6px 12px;
}

.box-nav {
  display: flex;
  gap: 14px;
  font-size: 14px;
  align-items: center;
}

.box-nav a {
  color: var(--mute);
}

.box-nav a.is-active,
.box-nav a:hover {
  color: var(--navy);
}

.box-nav .live {
  color: #fff;
  background: var(--navy);
  padding: 6px 12px;
}

.hero {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  min-height: 88vh;
  border-bottom: 2px solid var(--navy);
}

.hero-copy {
  padding: 8vh 6vw;
}

.kicker,
.vlabel {
  font-family: var(--mono);
  letter-spacing: 0.14em;
  font-size: 12px;
  color: var(--navy);
  margin: 0 0 12px;
}

h1,
h2,
h3 {
  font-family: var(--serif);
  font-weight: 700;
  line-height: 1.12;
  margin: 0 0 14px;
}

h1 {
  font-size: clamp(32px, 5vw, 60px);
}

h2 {
  font-size: clamp(24px, 3vw, 36px);
}

h3 {
  font-size: 20px;
}

.lead {
  color: var(--mute);
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 18px 0;
}

.chip {
  font-family: var(--mono);
  font-size: 11px;
  padding: 3px 8px;
  border: 1px solid var(--line);
  background: #fff;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  display: inline-flex;
  padding: 10px 16px;
  border: 2px solid var(--navy);
  font-size: 14px;
}

.btn-fill {
  background: var(--navy);
  color: #fff;
}

.btn-ghost {
  background: #fff;
}

.hero figure {
  margin: 0;
  background: var(--navy);
}

.hero figure img {
  width: 100%;
  height: 88vh;
  object-fit: cover;
}

.hero figcaption {
  font-family: var(--mono);
  font-size: 12px;
  color: #dce4f0;
  padding: 10px 14px;
}

.note {
  width: min(1080px, calc(100% - 48px));
  margin: 0 auto;
  padding: 80px 0;
}

.note-head {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 20px;
  margin-bottom: 32px;
}

.note-head p:last-child {
  margin: 0;
  color: var(--mute);
}

.three,
.six {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.three article,
.six article {
  background: #fff;
  padding: 18px;
  border-left: 4px solid var(--navy);
}

.three ul,
.io ul,
.rule-list {
  margin: 0;
  padding-left: 1.1em;
}

.ruled {
  background: #ece6d8;
}

.step {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  margin-bottom: 48px;
}

.step.rev {
  direction: rtl;
}

.step.rev > * {
  direction: ltr;
}

.idx {
  font-family: var(--mono);
  color: var(--navy);
  font-size: 12px;
}

.step figure {
  margin: 0;
  border: 2px solid var(--navy);
}

.step figure img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.step figcaption {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--mute);
  padding: 8px 10px;
  background: #fff;
}

.dial {
  margin-top: 12px;
  padding: 12px;
  border: 2px dashed var(--navy);
  background: #fff;
}

.dial-label {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--mute);
}

.slider {
  display: grid;
  grid-template-columns: 24px 1fr 40px;
  gap: 8px;
  align-items: center;
  font-size: 13px;
}

.slider input {
  width: 100%;
  accent-color: var(--navy);
}

.tri-state {
  margin: 8px 0 0;
  font-family: var(--mono);
  font-size: 13px;
}

.tri-state.ok {
  color: var(--ok);
}

.tri-state.warn {
  color: var(--warn);
}

.tri-state.late {
  color: #8a2a1a;
}

.rule-list {
  max-width: 46em;
}

.io {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.io > div {
  background: #fff;
  padding: 18px;
}

footer {
  padding: 24px 28px 36px;
  font-size: 13px;
  color: var(--mute);
  border-top: 2px solid var(--navy);
}

@media (max-width: 920px) {
  .hero,
  .note-head,
  .three,
  .six,
  .step,
  .io {
    grid-template-columns: 1fr;
  }

  .step.rev {
    direction: ltr;
  }

  .hero figure img {
    height: 42vh;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .box-nav {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    flex-direction: column;
    background: #fff;
    padding: 12px 20px 20px;
    gap: 10px;
  }

  .box-nav.open {
    display: flex;
  }
}