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

html {
  overflow-x: clip;
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
  background: var(--color-paper);
  color-scheme: dark;
}

body {
  margin: 0;
  min-height: 100dvh;
  overflow-x: clip;
  background: var(--color-paper);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-md);
  font-weight: 500;
  line-height: 1.55;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--color-accent); color: var(--color-accent-ink); }
* { scrollbar-color: var(--color-rule) var(--color-paper-3); }
body { caret-color: var(--color-accent); }

h1, h2, h3, h4 {
  margin: 0;
  min-width: 0;
  overflow-wrap: break-word;
  font-family: var(--font-display);
  font-weight: var(--display-weight);
  letter-spacing: var(--tracking-display);
  line-height: 1.04;
  text-wrap: balance;
}
h1 { font-size: var(--text-display); line-height: 0.98; max-width: 14ch; }
h2 { font-size: var(--text-section); max-width: 24ch; }
h3 { font-size: var(--text-title); max-width: 32ch; line-height: 1.15; }
p { margin: 0; text-wrap: pretty; }
ul, ol { margin: 0; padding: 0; }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
a:hover { text-decoration-color: var(--color-accent); }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
img, svg { display: block; max-width: 100%; }
img { height: auto; }
strong, b { font-weight: 700; }

:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
}
#main:focus, #main:focus-visible { outline: none; }

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

.section { padding-block: var(--section-gap); }
.section--tight { padding-block: var(--section-gap-s); }
.band {
  padding-block: var(--section-gap-s);
  background: var(--color-paper-2);
  color: var(--color-ink);
}
.section-head {
  display: grid;
  gap: var(--space-md);
  max-width: 62ch;
  margin-bottom: var(--space-2xl);
}
.lead {
  max-width: 60ch;
  color: var(--color-muted);
  font-size: var(--text-lead);
  line-height: 1.45;
}
.small { color: var(--color-muted); font-size: var(--text-sm); line-height: 1.5; }
.mono-num { font-variant-numeric: tabular-nums lining-nums; }

.skip {
  position: absolute;
  inset-inline-start: var(--space-md);
  top: calc(var(--space-3xl) * -1);
  z-index: var(--z-toast);
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--radius-control);
  background: var(--color-ink);
  color: var(--color-paper);
  font-weight: 700;
  text-decoration: none;
}
.skip:focus-visible { top: var(--space-md); }

.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon {
  width: 20px;
  height: 20px;
  flex: 0 0 auto;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.icon--small { width: 16px; height: 16px; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  min-height: 48px;
  padding: 0 var(--space-lg);
  border: var(--rule-bar) solid var(--color-ink);
  border-radius: var(--radius-control);
  background: transparent;
  color: var(--color-ink);
  font: 700 var(--text-md)/1.2 var(--font-body);
  white-space: nowrap;
  text-decoration: none;
  transition: background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out), transform var(--dur-micro) var(--ease-out);
}
.btn:hover { background: var(--color-paper-2); }
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 2px; }
.btn:disabled, .btn[aria-disabled="true"] { opacity: 0.55; cursor: not-allowed; transform: none; }
.btn[aria-busy="true"] { cursor: progress; }
.btn--primary {
  border-color: var(--color-accent);
  background: var(--color-accent);
  color: var(--color-accent-ink);
}
.btn--primary:hover { border-color: var(--color-accent-2); background: var(--color-accent-2); }
.btn--quiet { border-color: transparent; }
.btn--quiet:hover { background: var(--color-paper-2); }
.btn--wide { width: 100%; }
.btn--small { min-height: 40px; padding-inline: var(--space-md); font-size: var(--text-sm); }

.text-action {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  min-height: 44px;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--color-ink);
  font: 700 var(--text-sm)/1.2 var(--font-body);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
  transition: color var(--dur-micro) var(--ease-out), text-decoration-color var(--dur-micro) var(--ease-out);
}
.text-action:hover { color: var(--color-accent); text-decoration-color: var(--color-accent); }
.text-action:active { transform: translateY(1px); }
.text-action:disabled { opacity: 0.55; cursor: not-allowed; }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 0;
  border-radius: var(--radius-control);
  background: transparent;
  color: var(--color-ink);
  transition: background-color var(--dur-short) var(--ease-out);
}
.icon-btn:hover { background: var(--color-paper-3); }
.icon-btn:active { transform: translateY(1px); }

.meter {
  display: block;
  width: 100%;
  height: 6px;
  overflow: hidden;
  border-radius: var(--radius-pill);
  background: var(--color-paper-3);
}
.meter__fill {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--color-accent);
}

.tile {
  border-radius: var(--radius-card);
  background: var(--color-paper-2);
  padding: var(--space-xl);
}
.well {
  border-radius: var(--radius-card);
  background: var(--color-paper-3);
  padding: var(--space-xl);
}
.rule { height: var(--rule-hair); background: var(--color-rule); border: 0; }

.plain-list {
  display: grid;
  gap: 0;
  list-style: none;
  border-top: var(--rule-hair) solid var(--color-rule);
}
.plain-list li {
  padding-block: var(--space-sm);
  border-bottom: var(--rule-hair) solid var(--color-rule);
  color: var(--color-muted);
}
.steps {
  counter-reset: step;
  display: grid;
  gap: var(--space-md);
  list-style: none;
}
.steps li {
  counter-increment: step;
  display: grid;
  grid-template-columns: 2.2rem minmax(0, 1fr);
  gap: var(--space-sm);
  color: var(--color-muted);
}
.steps li::before {
  content: counter(step);
  color: var(--color-accent);
  font-family: var(--font-display);
  font-size: var(--text-title);
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}
.steps--small li { grid-template-columns: 1.6rem minmax(0, 1fr); gap: var(--space-xs); }
.steps--small li::before { font-size: var(--text-md); }

.status-line {
  min-height: 1lh;
  color: var(--color-muted);
  font-size: var(--text-sm);
}
.status-line[data-tone="error"] { color: var(--color-error); }
.status-line[data-tone="ok"] { color: var(--color-accent); }

.field {
  display: grid;
  gap: var(--space-2xs);
  color: var(--color-muted);
  font-size: var(--text-sm);
  font-weight: 700;
}
.field select,
.field input {
  width: 100%;
  min-height: 48px;
  padding: 0 var(--space-md);
  border: var(--rule-bar) solid var(--color-muted);
  border-radius: var(--radius-input);
  background: var(--color-paper-3);
  color: var(--color-ink);
  font-size: var(--text-md);
  font-weight: 500;
  outline: 2px solid transparent;
  outline-offset: -3px;
}
.field select:focus-visible,
.field input:focus-visible { outline-color: var(--color-focus); }
.field select:disabled { opacity: 0.55; cursor: not-allowed; }
.check {
  display: flex;
  align-items: flex-start;
  gap: var(--space-xs);
  min-height: 44px;
  color: var(--color-muted);
  font-size: var(--text-sm);
}
.check input {
  width: 20px;
  height: 20px;
  margin: 0;
  accent-color: var(--color-accent);
  flex: 0 0 auto;
}

.dialog {
  width: min(calc(100% - var(--gutter) * 2), 560px);
  max-height: calc(100dvh - var(--space-xl));
  padding: 0;
  border: 0;
  border-radius: var(--radius-card);
  background: var(--color-paper-2);
  color: var(--color-ink);
  box-shadow: var(--shadow-card);
}
.dialog::backdrop { background: var(--color-scrim); }
.dialog__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-lg) var(--space-lg) var(--space-sm);
}
.dialog__head h2 { font-size: var(--text-title); max-width: 20ch; }
.dialog__lead { padding-inline: var(--space-lg); color: var(--color-muted); }
.dialog__body {
  display: grid;
  gap: var(--space-md);
  padding: var(--space-lg);
}
.dialog .small { color: var(--color-muted); }

.details {
  border-top: var(--rule-hair) solid var(--color-rule);
  border-bottom: var(--rule-hair) solid var(--color-rule);
  padding-block: var(--space-sm);
}
.details summary {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  min-height: 44px;
  cursor: pointer;
  font-weight: 700;
}
.details summary::marker { color: var(--color-accent); }
.details[open] summary { margin-bottom: var(--space-sm); }

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

@media (max-width: 60rem) {
  :root {
    --gutter: 24px;
    --gap-columns: 24px;
    --section-gap-s: 80px;
    --section-gap: 96px;
    --section-gap-l: 120px;
  }
  .section { padding-block: var(--section-gap); }
}

@media (max-width: 40rem) {
  :root {
    --gutter: 16px;
    --gap-columns: 16px;
    --section-gap-s: 56px;
    --section-gap: 72px;
    --section-gap-l: 96px;
    --text-display: clamp(2.35rem, 12vw, 3.5rem);
    --text-display-s: clamp(2rem, 9vw, 2.8rem);
    --text-section: clamp(1.75rem, 8vw, 2.45rem);
    --text-lead: 1.0625rem;
  }
  h1 { max-width: 12ch; }
  .btn { min-height: 48px; }
  .tile, .well { padding: var(--space-lg); }
  .dialog { width: calc(100% - var(--space-lg) * 2); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

abbr[title] { text-decoration: none; cursor: help; }
.instrument__hint kbd {
  display: inline-grid;
  place-items: center;
  min-width: 20px;
  min-height: 20px;
  padding: 0 var(--space-3xs);
  border: 1px solid var(--color-rule);
  border-radius: 4px;
  font: 700 0.6875rem/1 var(--font-body);
  color: var(--color-ink);
}