@font-face {
  font-family: "D2Coding";
  src: url("fonts/D2Coding-Regular.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: "D2Coding";
  src: url("fonts/D2Coding-Bold.woff2") format("woff2");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

:root {
  --mono: "D2Coding", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;

  --bg: #fbfbf9;
  --surface: #ffffff;
  --surface-2: #f3f3f0;
  --text: #16181c;
  --muted: #656a72;
  --border: #e2e2dd;
  --accent: #03864a;
  --accent-soft: #03c75a1f;
  --warn: #b3541e;
  --shadow: 0 1px 2px rgba(20, 22, 26, .06), 0 8px 24px rgba(20, 22, 26, .05);
  --radius: 10px;
  --tok-kw: #8250df;
  --tok-str: #0a69da;
  --tok-fn: #953800;
  --tok-type: #b35900;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101216;
    --surface: #171a1f;
    --surface-2: #1e2229;
    --text: #e9eaec;
    --muted: #9aa1ab;
    --border: #2a2f38;
    --accent: #22d67f;
    --accent-soft: #03c75a24;
    --warn: #e39a5c;
    --shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .3);
    --tok-kw: #b794f6;
    --tok-str: #6cb6ff;
    --tok-fn: #f0883e;
    --tok-type: #e3b341;
  }
}

:root[data-theme="light"] {
  --bg: #fbfbf9;
  --surface: #ffffff;
  --surface-2: #f3f3f0;
  --text: #16181c;
  --muted: #656a72;
  --border: #e2e2dd;
  --accent: #03864a;
  --accent-soft: #03c75a1f;
  --warn: #b3541e;
  --shadow: 0 1px 2px rgba(20, 22, 26, .06), 0 8px 24px rgba(20, 22, 26, .05);
  --tok-kw: #8250df;
  --tok-str: #0a69da;
  --tok-fn: #953800;
  --tok-type: #b35900;
}

:root[data-theme="dark"] {
  --bg: #101216;
  --surface: #171a1f;
  --surface-2: #1e2229;
  --text: #e9eaec;
  --muted: #9aa1ab;
  --border: #2a2f38;
  --accent: #22d67f;
  --accent-soft: #03c75a24;
  --warn: #e39a5c;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .3);
  --tok-kw: #b794f6;
  --tok-str: #6cb6ff;
  --tok-fn: #f0883e;
  --tok-type: #e3b341;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}

a { color: inherit; text-decoration-color: color-mix(in srgb, currentColor 35%, transparent); text-underline-offset: 3px; }
a:hover { text-decoration-color: currentColor; }

code {
  font-family: var(--mono);
  font-size: .92em;
  background: var(--surface-2);
  border-radius: 4px;
  padding: .1em .35em;
}

.skip {
  position: absolute;
  left: -9999px;
}
.skip:focus {
  left: 1rem;
  top: 1rem;
  z-index: 10;
  background: var(--surface);
  padding: .5rem .9rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

/* ---------- layout ---------- */

.hero, .section, .footer {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2.5rem);
}

.section { padding-top: clamp(3rem, 7vw, 5.5rem); }

.section-head { max-width: 62ch; margin-bottom: 1.75rem; }
.section-head h2 {
  font-family: var(--mono);
  font-size: clamp(1.35rem, 3vw, 1.8rem);
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 0 0 .5rem;
}
.section-head p { margin: 0; color: var(--muted); }

.note { color: var(--muted); font-size: .93rem; max-width: 68ch; }

/* ---------- nav + hero ---------- */

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem 0;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.nav-mark { font-family: var(--mono); font-weight: 700; letter-spacing: -.02em; }
.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(.6rem, 2vw, 1.2rem);
  font-family: var(--mono);
  font-size: .84rem;
  flex-wrap: wrap;
}
.nav-links a { text-decoration: none; color: var(--muted); }
.nav-links a:hover { color: var(--text); }

.theme-toggle {
  font: inherit;
  font-family: var(--mono);
  color: var(--muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: .15rem .7rem;
  cursor: pointer;
  min-width: 5.2em;
}
.theme-toggle:hover { color: var(--text); }

.hero-body { padding: clamp(2.5rem, 8vw, 5rem) 0 0; }
.hero-title {
  font-family: var(--mono);
  font-weight: 700;
  font-size: clamp(2.6rem, 11vw, 7rem);
  line-height: 1;
  letter-spacing: -.04em;
  margin: 0 0 1.25rem;
}
.hero-sub {
  max-width: 56ch;
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  color: var(--muted);
  margin: 0 0 1.75rem;
}
.hero-actions { display: flex; gap: .6rem; flex-wrap: wrap; margin-bottom: 2.5rem; }

.btn {
  font-family: var(--mono);
  font-size: .88rem;
  text-decoration: none;
  padding: .55rem 1.05rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  transition: border-color .15s, background .15s;
}
.btn:hover { border-color: color-mix(in srgb, var(--accent) 55%, var(--border)); }
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: 700;
}
:root[data-theme="dark"] .btn-primary,
:root:not([data-theme="light"]) .btn-primary { color: #0b1a12; }
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .btn-primary { color: #fff; }
}
.btn-primary:hover { filter: brightness(1.06); }

.hero-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1px;
  margin: 0 0 1.75rem;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.hero-stats > div { background: var(--surface); padding: .9rem 1.1rem; }
.hero-stats dt { font-size: .74rem; text-transform: uppercase; letter-spacing: .09em; color: var(--muted); }
.hero-stats dd { font-family: var(--mono); font-size: 1.35rem; font-weight: 700; margin: .15rem 0 0; }

.hero-note { max-width: 64ch; color: var(--muted); font-size: .93rem; }

/* ---------- controls ---------- */

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 1.25rem 1.75rem;
  padding: 1.25rem 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 1rem;
}
.control { display: flex; flex-direction: column; gap: .5rem; }
.control-label {
  font-family: var(--mono);
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  gap: .5rem;
}
.control-label output { color: var(--text); text-transform: none; letter-spacing: 0; }

input[type="range"] { width: 100%; accent-color: var(--accent); }

.toggles { display: flex; flex-wrap: wrap; gap: .4rem .9rem; }
.switch {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  font-family: var(--mono);
  font-size: .82rem;
  cursor: pointer;
}
.switch input { accent-color: var(--accent); }

.samples { display: flex; flex-wrap: wrap; gap: .4rem; margin-bottom: 1rem; }
.chip {
  font-family: var(--mono);
  font-size: .8rem;
  padding: .35rem .8rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
  cursor: pointer;
}
.chip:hover { color: var(--text); }
.chip.is-active {
  background: var(--accent-soft);
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
  color: var(--text);
}

/* ---------- type surfaces ---------- */

.editor-wrap, .specimen, .report {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.editor, .specimen {
  font-family: var(--mono);
  font-size: var(--type-size, 15px);
  line-height: var(--type-leading, 1.55);
  letter-spacing: var(--type-tracking, 0);
  font-weight: var(--type-weight, 400);
  font-variant-ligatures: var(--type-liga, contextual);
  font-feature-settings: var(--type-features, "calt" 1);
  -webkit-font-smoothing: var(--type-smoothing, antialiased);
}

.editor {
  display: block;
  width: 100%;
  min-height: 22rem;
  resize: vertical;
  padding: 1.25rem 1.5rem;
  border: 0;
  background: transparent;
  color: inherit;
  tab-size: 4;
  white-space: pre;
  overflow: auto;
}
.editor:focus { outline: 2px solid color-mix(in srgb, var(--accent) 60%, transparent); outline-offset: -2px; }

.specimen {
  margin: 0;
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  white-space: pre;
}

.is-grid .editor, .is-grid .specimen {
  background-image:
    repeating-linear-gradient(to right,
      color-mix(in srgb, var(--accent) 22%, transparent) 0 1px,
      transparent 1px var(--cell, 1ch));
  background-position: 1.5rem 0;
  background-origin: content-box;
}

/* ---------- ligatures ---------- */

#lig-mixed-demo { margin-bottom: .85rem; }
#ligatures .note { margin: 0 0 2rem; }

.lig-groups { display: grid; gap: 1.75rem; }
.lig-group h3 {
  font-family: var(--mono);
  font-size: .8rem;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--muted);
  margin: 0 0 .75rem;
  font-weight: 400;
}
.lig-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(104px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.lig {
  background: var(--surface);
  padding: .85rem .5rem .6rem;
  text-align: center;
}
.lig b {
  display: block;
  font-family: var(--mono);
  font-weight: 400;
  font-size: 1.5rem;
  line-height: 1.3;
  font-variant-ligatures: contextual;
  font-feature-settings: "calt" 1;
}
.lig span {
  display: block;
  font-family: var(--mono);
  font-size: .72rem;
  color: var(--muted);
  font-variant-ligatures: none;
  font-feature-settings: "calt" 0;
  white-space: pre;
}

/* ---------- comparison table ---------- */

.compare {
  margin: 0 0 1.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow-x: auto;
}
.compare table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
}
.compare th, .compare td {
  padding: .5rem .95rem;
  border-top: 1px solid var(--border);
  text-align: left;
  vertical-align: middle;
}
.compare tr > * + * { border-left: 1px solid var(--border); }
.compare thead th {
  border-top: 0;
  font-family: var(--mono);
  font-weight: 400;
  font-size: .74rem;
  text-transform: uppercase;
  letter-spacing: .09em;
  color: var(--muted);
}
.compare tbody th {
  font-family: var(--mono);
  font-weight: 400;
  font-size: .8rem;
  color: var(--muted);
  white-space: nowrap;
}
.compare .compare-group {
  font-size: .74rem;
  text-transform: uppercase;
  letter-spacing: .09em;
}
.compare td {
  font-size: 1.4rem;
  line-height: 1.3;
  white-space: nowrap;
}
.compare .row-sans td { font-family: sans-serif; }
.compare .row-mono td { font-family: monospace; }
.compare .row-d2 td { font-family: "D2Coding", monospace; }
.compare .row-d2 { background: var(--accent-soft); }
.compare .row-d2 th { color: var(--text); }
.compare figcaption {
  padding: .8rem 1rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: .88rem;
}

/* ---------- confusables ---------- */

.confuse-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(215px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.confuse { background: var(--surface); padding: 1rem .9rem; }
.confuse b {
  display: block;
  font-family: var(--mono);
  font-weight: var(--type-weight, 400);
  font-size: min(calc(var(--type-size, 15px) * 2.2), 30px);
  line-height: 1.4;
  letter-spacing: .04em;
  white-space: nowrap;
  -webkit-font-smoothing: var(--type-smoothing, antialiased);
}
.confuse span { display: block; font-size: .78rem; color: var(--muted); margin-top: .35rem; }

/* ---------- highlighted code sample ---------- */

.code-figure { margin: 1.75rem 0 0; }
.code-sample { font-size: calc(var(--type-size, 15px) + 2px); }
.code-sample code {
  font: inherit;
  background: none;
  border-radius: 0;
  padding: 0;
}
.code-figure figcaption {
  color: var(--muted);
  font-size: .88rem;
  margin-top: .6rem;
}
.tok-cmt { color: var(--accent); }
.tok-kw { color: var(--tok-kw); }
.tok-str { color: var(--tok-str); }
.tok-fn { color: var(--tok-fn); }
.tok-type { color: var(--tok-type); }

/* ---------- verify tools ---------- */

.tool {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.4rem 1.5rem;
  margin-bottom: 1.25rem;
}
.tool h3 { font-family: var(--mono); font-size: 1.05rem; margin: 0 0 .35rem; }
.tool-note { color: var(--muted); font-size: .92rem; margin: 0 0 1rem; max-width: 70ch; }

.field { display: block; margin-bottom: 1rem; }
.field > span {
  display: block;
  font-family: var(--mono);
  font-size: .76rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  margin-bottom: .4rem;
}
.field input, .field textarea {
  width: 100%;
  font-family: var(--mono);
  font-size: .95rem;
  padding: .6rem .75rem;
  color: inherit;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  resize: vertical;
}
.field input:focus, .field textarea:focus {
  outline: 2px solid color-mix(in srgb, var(--accent) 60%, transparent);
  outline-offset: -1px;
}

.ladder {
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow-x: auto;
}
.ladder-row {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: .4rem .85rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
.ladder-row:last-child { border-bottom: 0; }
.ladder-row i {
  font-family: var(--mono);
  font-style: normal;
  font-size: .72rem;
  color: var(--muted);
  min-width: 3.2em;
  flex: none;
}
.ladder-row samp {
  font-family: var(--mono);
  font-weight: var(--type-weight, 400);
  font-variant-ligatures: var(--type-liga, contextual);
  font-feature-settings: var(--type-features, "calt" 1);
  -webkit-font-smoothing: var(--type-smoothing, antialiased);
}

.cov-result { font-size: .95rem; }
.cov-ok { color: var(--accent); font-family: var(--mono); font-size: .9rem; }
.cov-missing { color: var(--warn); font-family: var(--mono); font-size: .9rem; margin-bottom: .5rem; }
.cov-list { display: flex; flex-wrap: wrap; gap: .35rem; }
.cov-item {
  font-family: var(--mono);
  font-size: .8rem;
  border: 1px dashed color-mix(in srgb, var(--warn) 50%, var(--border));
  border-radius: 6px;
  padding: .2rem .5rem;
  color: var(--muted);
}
.cov-item b { color: var(--text); font-weight: 400; }

.report {
  font-family: var(--mono);
  font-size: .82rem;
  line-height: 1.6;
  padding: 1rem 1.15rem;
  margin: 0 0 1rem;
  overflow-x: auto;
  white-space: pre;
  background: var(--surface-2);
  box-shadow: none;
}

/* ---------- footer ---------- */

.footer {
  margin-top: clamp(3.5rem, 8vw, 6rem);
  padding-top: 2rem;
  padding-bottom: 3rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: .9rem;
}
.footer p { margin: .35rem 0; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}