/* caisson site — the page is the emblem: sky, bridge, water, bedrock.
   Theming: day/night variables set below; night applies either through
   the system preference (no override stored, or no JS) or through
   html[data-theme="dark"] set by the toggle. */

:root {
  --iron: #43464B;
  --iron-soft: #5C6167;
  --fog-light: #D8DBDE;
  --fog-lighter: #E4E6E9;
  --deep-water: #27394E;
  --bedrock: #1B2635;
  --nix-blue: #5277C3;
  --nix-sky: #7EBAE4;
  --gold: #C9A227;
  --violet: #7F5AB6;

  /* day theme */
  --t-bg: var(--fog-light);
  --t-text: var(--iron);
  --t-link: var(--nix-blue);
  --t-sky-hi: var(--fog-lighter);
  --t-sky-lo: var(--fog-light);
  --t-muted: var(--iron-soft);
  --t-ghost-text: var(--iron);
  --t-ghost-border: var(--iron-soft);
  --t-pre-bg: var(--bedrock);
  --t-pre-text: #D5DCE4;
  --t-comment: #8A97A6;
  --t-water-bg: var(--deep-water);
  --t-h2: #E4E6E9;
  --t-bedrock-bg: var(--bedrock);
  --bb-struct: var(--iron);
  --bb-struct-op: 0.8;
  --bb-susp-disp: initial;
  --bb-led-disp: none;
  --bb-embellish-disp: none;
  --bb-waterline: var(--bedrock);
  --bb-caisson: #2E4158;
  --bb-violet-op: 0.18;
  --toggle-glyph: "\263E"; /* offer the moon by day */
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --t-bg: #151B24;
    --t-text: #C7CCD3;
    --t-link: var(--nix-sky);
    --t-sky-hi: #171D27;
    --t-sky-lo: #131820;
    --t-muted: #93A0AE;
    --t-ghost-text: #C7CCD3;
    --t-ghost-border: #93A0AE;
    --t-pre-bg: #090E15;
    --t-pre-text: #C7CCD3;
    --t-comment: #6C7886;
    --t-water-bg: #0E141D;
    --t-h2: #D8DBDE;
    --t-bedrock-bg: #090E15;
    --bb-struct: #39414C;
    --bb-struct-op: 0.9;
    --bb-susp-disp: none;
    --bb-led-disp: initial;
    --bb-embellish-disp: initial;
    --bb-waterline: #05080C;
    --bb-caisson: #1C2836;
    --bb-violet-op: 0.25;
    --toggle-glyph: "\2600"; /* offer the sun by night */
  }
}

:root[data-theme="dark"] {
  --t-bg: #151B24;
  --t-text: #C7CCD3;
  --t-link: var(--nix-sky);
  --t-sky-hi: #171D27;
  --t-sky-lo: #131820;
  --t-muted: #93A0AE;
  --t-ghost-text: #C7CCD3;
  --t-ghost-border: #93A0AE;
  --t-pre-bg: #090E15;
  --t-pre-text: #C7CCD3;
  --t-comment: #6C7886;
  --t-water-bg: #0E141D;
  --t-h2: #D8DBDE;
  --t-bedrock-bg: #090E15;
  --bb-struct: #39414C;
  --bb-struct-op: 0.9;
  --bb-susp-disp: none;
  --bb-led-disp: initial;
  --bb-embellish-disp: initial;
  --bb-waterline: #05080C;
  --bb-caisson: #1C2836;
  --bb-violet-op: 0.25;
  --toggle-glyph: "\2600";
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: Inter, "IBM Plex Sans", system-ui, sans-serif;
  line-height: 1.6;
  color: var(--t-text);
  background: var(--t-bg);
}

::selection { background: var(--violet); color: #fff; }

a { color: var(--t-link); text-decoration: none; }
a:hover { text-decoration: underline; }

/* --- sky --- */

.sky {
  background: linear-gradient(var(--t-sky-hi), var(--t-sky-lo));
  padding: 0 1.5rem;
}

nav {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1.25rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  font-weight: 600;
  letter-spacing: -0.02em;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.brand img { border-radius: 6px; }

.links { display: inline-flex; align-items: center; gap: 1.25rem; }

.links a { color: var(--t-muted); }

.theme-toggle {
  background: none;
  border: none;
  padding: 0.1rem 0.3rem;
  cursor: pointer;
  font-size: 1.05rem;
  line-height: 1;
  color: var(--t-muted);
}

.theme-toggle::after { content: var(--toggle-glyph); }

.theme-toggle:hover { color: var(--t-text); }

/* the hero sits in the valley of the cables */

.hero-scene {
  position: relative;
  background: var(--t-sky-lo);
  /* past the width where the text-driven height would squash the scene,
     grow with the viewport at the scene's own aspect ratio */
  min-height: 48.4375vw;
}

/* the text drives the container height; the scene is a backdrop that
   covers it, so the deck always clears the reserved bottom band */
.hero {
  position: relative;
  z-index: 1;
  padding: 2.25rem 1.5rem 400px;
  text-align: center;
}

.hero h1 {
  font-size: clamp(2.5rem, 5.5vw, 4.25rem);
  font-weight: 500;
  letter-spacing: -0.03em;
  margin: 0;
}

.tagline {
  font-size: clamp(1rem, 1.9vw, 1.35rem);
  color: var(--t-muted);
  margin: 0.25rem 0 1.25rem;
}

.lede {
  max-width: 38rem;
  margin: 0 auto;
}

.hero-actions { margin: 1.5rem 0 0; }

@media (max-width: 900px) {
  .hero {
    text-align: left;
    max-width: 46rem;
    margin: 0 auto;
    padding: 2.5rem 1.5rem 1rem;
  }
  .lede { margin: 0; }
}

.button {
  display: inline-block;
  padding: 0.55rem 1.2rem;
  border-radius: 8px;
  background: var(--nix-blue);
  color: #fff;
  font-weight: 500;
  margin-right: 0.75rem;
}

.button:hover { text-decoration: none; filter: brightness(1.08); }

.button.ghost {
  background: var(--t-sky-lo);
  color: var(--t-ghost-text);
  border: 1px solid var(--t-ghost-border);
}

/* --- the bridge band --- */

.bridge-band {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

@media (max-width: 900px) {
  .bridge-band {
    position: static;
    height: 380px;
  }
}

.bb-sky { fill: var(--t-sky-lo); }
.bb-water { fill: var(--t-water-bg); }
.bb-structure { stroke: var(--bb-struct); opacity: var(--bb-struct-op); }
.bb-susp { display: var(--bb-susp-disp); }
.bb-led { stroke: #E8ECF2; display: var(--bb-led-disp); }
.bb-cover { display: var(--bb-embellish-disp); stroke: var(--t-sky-lo); }
.bb-bloom { display: var(--bb-embellish-disp); stroke: #E8ECF2; }
.bb-anchorage { fill: var(--bb-struct); }
.bb-waterline { stroke: var(--bb-waterline); }
.bb-caisson { fill: var(--bb-caisson); stroke: var(--nix-sky); }
.bb-walls { stroke: var(--nix-blue); }
.bb-violet { fill: var(--violet); fill-opacity: var(--bb-violet-op); }
.bb-lambda { stroke: var(--nix-blue); }
.bb-rivet { fill: var(--gold); }

/* --- water --- */

.water {
  background: var(--t-water-bg);
  color: #C9CDD2;
  padding: 3rem 1.5rem 4rem;
}

.water a { color: var(--nix-sky); }

.water h2 {
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--t-h2);
}

.water pre code { background: none; }

.water code {
  background: rgba(126, 186, 228, 0.12);
  padding: 0.1em 0.35em;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: "JetBrains Mono", "Fira Code", ui-monospace, monospace;
}

pre {
  background: var(--t-pre-bg);
  color: var(--t-pre-text);
  padding: 1.1rem 1.3rem;
  border-radius: 10px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
  border-bottom: 3px solid var(--nix-blue);
  margin: 0;
}

pre code { background: none; padding: 0; font-size: inherit; }

pre .c { color: var(--t-comment); }

.features {
  max-width: 62rem;
  margin: 0 auto;
  display: grid;
  gap: 2.5rem;
}

.feature {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 2rem;
  align-items: center;
}

.feature:nth-child(even) pre { order: -1; }

@media (max-width: 46rem) {
  .feature { grid-template-columns: 1fr; }
  .feature:nth-child(even) pre { order: 0; }
}

.get-started, .design, .integrations {
  max-width: 46rem;
  margin: 3.5rem auto 0;
}

.steps { padding-left: 1.25rem; }
.steps li { margin-bottom: 0.5rem; }
.get-started pre { margin: 1.25rem 0; }

.design h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--t-h2);
  margin-top: 2rem;
}

.design pre { margin: 1.25rem 0; }

.where {
  border-collapse: collapse;
  width: 100%;
  margin: 1.25rem 0;
  font-size: 0.95rem;
}

.where th {
  text-align: left;
  color: var(--t-h2);
  border-bottom: 2px solid var(--nix-blue);
  padding: 0.4rem 0.75rem 0.4rem 0;
}

.where td {
  vertical-align: top;
  border-bottom: 1px solid rgba(126, 186, 228, 0.18);
  padding: 0.55rem 0.75rem 0.55rem 0;
}

/* --- bedrock --- */

.bedrock {
  background: var(--t-bedrock-bg);
  color: #8A97A6;
  text-align: center;
  padding: 1.5rem;
  font-size: 0.9rem;
}

.bedrock a { color: #A9B4C0; }

.colophon { font-size: 0.8rem; opacity: 0.8; margin-bottom: 0; }