/* The coming-soon page and the style guide share this sheet.
   Graph paper is the page. Plots are instruments set on a clean well. */

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

[hidden] { display: none !important; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(to right, var(--grid-10) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-10) 1px, transparent 1px),
    linear-gradient(to right, var(--grid-5) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-5) 1px, transparent 1px),
    linear-gradient(to right, var(--grid-1) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-1) 1px, transparent 1px);
  background-size: 10mm 10mm, 10mm 10mm, 5mm 5mm, 5mm 5mm, 1mm 1mm, 1mm 1mm;
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.55;
  font-optical-sizing: auto;
}

::selection {
  background: rgba(226, 74, 27, 0.22);
  color: var(--ink);
}

:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 5;
  background: var(--well);
  color: var(--ink);
  border: 1px solid var(--ink);
  padding: 0.4rem 0.7rem;
  font-family: var(--font-sans);
}

.skip:focus { top: 1rem; }

.wrap {
  width: min(var(--wrap), calc(100% - 2 * var(--pad)));
  margin-inline: auto;
}

h1, h2, h3, .sans, .display-lock {
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 0.96;
}

h1, h2, h3 { margin: 0; }

a { color: inherit; }

.sr {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.mast {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1.15rem 0 0.4rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  text-decoration: none;
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: -0.03em;
  font-size: 1.15rem;
}

.brand svg { width: 36px; height: 36px; display: block; }

.mast-meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.hero { padding: 1.2rem 0 0.4rem; }

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(280px, 0.72fr);
  grid-template-areas:
    "copy card"
    "index index";
  gap: 1.15rem 2.25rem;
  align-items: start;
}

.copy { grid-area: copy; }
.firm-language { color: var(--orange); }
.seat-card { grid-area: card; align-self: stretch; }
.index { grid-area: index; }

.kicker {
  margin: 0 0 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.hero h1,
.hero .display-lock {
  font-size: clamp(3.15rem, 6.6vw, 5.5rem);
  letter-spacing: -0.05em;
  line-height: 0.86;
  margin: 0 0 0.9rem;
}

.hero h1 .line,
.hero .display-lock .line { display: block; }

.hero h1 .big,
.hero .display-lock .big {
  color: var(--orange);
  font-size: 1.16em;
  letter-spacing: -0.055em;
}

.subhead, .lede {
  max-width: 38rem;
  margin: 0;
  font-size: 1.22rem;
  line-height: 1.45;
}

.seat-card {
  display: flex;
  flex-direction: column;
  background: var(--well);
  border: 1px solid var(--ink);
  box-shadow: 7px 7px 0 var(--ink);
  padding: 1.25rem 1.2rem 1.1rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.field label { font-size: 1.2rem; line-height: 1.35; }

.field input[type="email"],
.specimen-input {
  width: 100%;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 1rem;
  padding: 0.75rem 0.7rem;
}

.button {
  margin-top: 0.75rem;
  width: 100%;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--well);
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: -0.02em;
  font-size: 1rem;
  padding: 0.8rem 1rem;
  cursor: pointer;
}

.button:hover {
  background: var(--well);
  color: var(--ink);
  border-color: var(--orange);
}

.form-error {
  margin: 0.4rem 0 0;
  color: var(--orange-ink);
  font-size: 0.98rem;
}

.success-title {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1.7rem;
  letter-spacing: -0.04em;
  color: var(--green-ink);
}

.hp {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.countdown { margin-top: auto; padding-top: 1.2rem; }

.countdown-label { margin: 0; font-size: 1.05rem; }

.countdown-zone {
  margin: 0.28rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.countdown-status {
  margin: 0.35rem 0 0;
  min-height: 1.2rem;
  font-family: var(--font-sans);
  font-weight: 600;
  color: var(--green-ink);
}

.countdown-axis {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: 0.8rem;
}

.countdown-axis::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 1.7rem;
  border-top: 1px solid var(--ink);
}

.tick { text-align: center; }

.tick span {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.55rem;
  letter-spacing: -0.04em;
  line-height: 1;
}

.tick small {
  display: block;
  margin-top: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.plot {
  height: 340px;
  background: var(--well);
  border: 1px solid var(--ink);
}

.hero-plot .plot { height: 420px; }

.plot canvas {
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
  cursor: crosshair;
}

.caption, .readout, .hint, .slider-row label, .slider-row output, .value {
  font-family: var(--font-mono);
}

.caption, .readout {
  margin: 0.45rem 0 0;
  font-size: 0.82rem;
}

.hint {
  margin: 0.35rem 0 0;
  font-size: 0.72rem;
  letter-spacing: 0.02em;
  color: var(--muted);
}

.slider-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.15rem 1rem;
  align-items: center;
  margin-top: 0.75rem;
}

.slider-row label {
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.slider-row output, .value { font-size: 0.85rem; }

.slider-row input[type="range"] { grid-column: 1 / -1; }

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 1.7rem;
  margin: 0;
  background: transparent;
  cursor: pointer;
}

input[type="range"]:focus-visible { outline: none; }

input[type="range"]::-webkit-slider-runnable-track {
  height: 1px;
  background: var(--ink);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  margin-top: -7px;
  border-radius: 50%;
  background: var(--well);
  border: 2px solid var(--orange);
}

input[type="range"]:focus-visible::-webkit-slider-thumb {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
}

input[type="range"]::-moz-range-track {
  height: 1px;
  background: var(--ink);
  border: 0;
}

input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border: 2px solid var(--orange);
  border-radius: 50%;
  background: var(--well);
}

.index {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.2rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.index a {
  text-decoration: none;
  border-bottom: 1px solid var(--rule);
}

.index a:hover { border-bottom-color: var(--orange); color: var(--orange-ink); }

.chapter {
  margin-top: 4.2rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--rule);
}

.chapter h2 {
  font-size: clamp(2rem, 4vw, 3.15rem);
  margin: 0.15rem 0 0.7rem;
}

.chapter[data-accent="orange"] .kicker { color: var(--orange-ink); }
.chapter[data-accent="green"] .kicker { color: var(--green-ink); }

.formula {
  margin: 0.8rem 0 0.2rem;
  font-size: 1.25rem;
  overflow-x: auto;
}

.term, .term-inline {
  cursor: help;
  border-bottom: 1px dotted rgba(16, 36, 63, 0.4);
}

.term-inline {
  font: inherit;
  color: inherit;
  background: none;
  padding: 0;
  border-width: 0 0 1px;
  border-style: dotted;
  border-color: rgba(16, 36, 63, 0.4);
}

.term:hover, .term:focus-visible,
.term-inline:hover, .term-inline:focus-visible {
  background: rgba(226, 74, 27, 0.14);
  border-bottom-color: var(--orange);
}

.pair {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 6.5rem minmax(0, 1fr);
  gap: 0.75rem;
  align-items: stretch;
  margin-top: 1rem;
}

.gutter {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.3rem;
  border-inline: 1px solid var(--rule);
}

.gutter-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--orange-ink);
}

.gutter-value {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1.5rem;
  letter-spacing: -0.04em;
  color: var(--orange);
}

.switch {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.2rem;
  margin: 0.9rem 0 0.2rem;
}

.switch button {
  background: none;
  border: 0;
  border-bottom: 2px solid transparent;
  padding: 0.15rem 0;
  font-family: var(--font-sans);
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
}

.switch button[aria-checked="true"],
.switch button[aria-selected="true"] { border-bottom-color: var(--orange); }

.text-button {
  margin-top: 0.7rem;
  background: none;
  border: 0;
  border-bottom: 1px solid var(--rule);
  padding: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink);
  cursor: pointer;
}

.text-button:hover { border-bottom-color: var(--orange); color: var(--orange-ink); }

.toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

#delta-state.is-holding { color: var(--green-ink); }

.proof-sheet {
  margin-top: 0.8rem;
  background: var(--well);
  border: 1px solid var(--ink);
  padding: 0.4rem 1rem 0.2rem;
}

.step {
  display: grid;
  grid-template-columns: 2rem minmax(0, 1fr);
  gap: 0.55rem;
  padding: 0.75rem 0;
  border-top: 1px solid var(--rule);
}

.step:first-child { border-top: 0; }

.step.is-current {
  box-shadow: inset 3px 0 0 var(--orange);
  padding-left: 0.55rem;
}

.step-num {
  font-family: var(--font-mono);
  color: var(--orange-ink);
}

.step p { margin: 0; }

.step .formula { font-size: 1.15rem; }

.proof-controls {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin-top: 0.8rem;
}

.proof-controls .button { width: auto; margin-top: 0; padding-inline: 1.1rem; }

.popover {
  position: fixed;
  z-index: 30;
  width: min(280px, calc(100vw - 24px));
  padding: 0.75rem 0.85rem 0.85rem;
  background: var(--well);
  border: 1px solid var(--ink);
  box-shadow: 4px 4px 0 var(--ink);
  pointer-events: none;
}

.popover.is-static {
  position: relative;
  left: auto !important;
  top: auto !important;
  display: block;
  margin-top: 0.6rem;
}

.popover-symbol, .popover-name, .popover-text { margin: 0; }

.popover-symbol {
  font-family: var(--font-mono);
  color: var(--orange-ink);
}

.popover-name {
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: -0.03em;
  margin-top: 0.1rem;
}

.popover-text {
  margin-top: 0.35rem;
  font-size: 0.98rem;
  line-height: 1.4;
}

.foot {
  margin: 4rem 0 2rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--ink);
}

.countdown.compact { margin-top: 0; padding-top: 0; }

.countdown.compact .tick span { font-size: 1.15rem; }

.countdown.compact .countdown-axis::before { top: 1.35rem; }

.foot-note, .foot-links {
  margin: 0.9rem 0 0;
  font-size: 1rem;
}

.foot-links {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.foot-links a { text-decoration: none; border-bottom: 1px solid var(--rule); }

.noscript {
  margin-top: 1rem;
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.guide h1 {
  font-size: clamp(2.8rem, 6vw, 4.6rem);
  margin: 0.2rem 0 0.7rem;
}

.swatches {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 0.75rem;
  margin-top: 1rem;
}

.swatch {
  min-height: 8.5rem;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  border: 1px solid var(--ink);
  background: var(--swatch, var(--paper));
  padding: 0.7rem 0.7rem 0;
}

.swatch .meta {
  background: var(--paper);
  color: var(--ink);
  margin: 0.55rem -0.7rem 0;
  padding: 0.45rem 0.7rem 0.55rem;
}

.swatch strong, .swatch span { display: block; }

.swatch strong {
  font-family: var(--font-sans);
  letter-spacing: -0.03em;
}

.swatch span {
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.sample-orange { color: var(--orange-ink); font-family: var(--font-sans); font-weight: 600; }
.sample-green { color: var(--green-ink); font-family: var(--font-sans); font-weight: 600; }

.code {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  background: var(--well);
  border: 1px solid var(--ink);
  padding: 0.8rem 1rem;
  overflow-x: auto;
}

.rules { padding-left: 1.1rem; }
.rules li { margin: 0.25rem 0; }

.motion-list {
  display: grid;
  grid-template-columns: 14rem 1fr;
  gap: 0.35rem 1rem;
  margin: 0.8rem 0 0;
}

.motion-list dt {
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.motion-list dd { margin: 0; }

.guide .plot { height: 280px; margin-top: 0.8rem; }

@media (max-width: 860px) {
  .hero-grid {
    grid-template-columns: 1fr;
    grid-template-areas: "copy" "card" "index";
  }

  .hero h1 { font-size: clamp(2.7rem, 14vw, 4rem); }
  .hero-plot .plot, .plot { height: 280px; }
  .pair { grid-template-columns: 1fr; }
  .gutter {
    flex-direction: row;
    justify-content: space-between;
    min-height: 3rem;
    padding-inline: 0.4rem;
    border-inline: 0;
    border-block: 1px solid var(--rule);
  }
  .motion-list { grid-template-columns: 1fr; }
  .tick span { font-size: 1.25rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}