Topographic signal

<!-- Original layout, SVG/CSS artwork and JavaScript © 2026 XXC Templates. MIT License.
Illustrative sample content and data; no real accounts, purchases or bookings. -->
<main>
  <header class="intro">
    <div>
      <div class="kicker">GENERATIVE / CONTOURS</div>
      <h1>Topographic signal</h1>
      <p>A quiet topography made from one family of spline curves.</p>
    </div>
  </header>
  <div class="stage">
    <svg
      id="terrain"
      viewBox="0 0 700 300"
      role="img"
      aria-label="Interactive contour line landscape"
    ></svg>
  </div>
  <div class="toolbar">
    <button id="reseed">Explore another terrain</button
    ><span class="badge">MOVE ACROSS THE MAP</span>
  </div>
  <output id="status" class="status" aria-live="polite"></output>
</main>

:root {
  --bg: #071c2a;
  --panel: #0c293b;
  --text: #e3f9fc;
  --muted: #92b8c8;
  --line: #245065;
  --accent: #64dfd7;
}
/* Original XXC Templates Studio collection. MIT; sample data only. */
* {
  box-sizing: border-box;
}
html {
  color-scheme: dark;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font:
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    -apple-system,
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  padding: clamp(18px, 4vw, 40px);
  min-height: 100vh;
}
h1,
h2,
h3,
p {
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h1 {
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  letter-spacing: -0.055em;
  font-weight: 650;
}
h2 {
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  letter-spacing: -0.025em;
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}
h3 {
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}
p {
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}
button,
input,
select {
  font: inherit;
}
button,
a,
input,
select,
summary {
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}
button {
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  background: var(--panel);
  border: 1px solid var(--line);
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  padding: 9px 14px;
  font-size: 12px;
}
button:hover {
  border-color: var(--accent);
}
button[aria-pressed="true"],
button.active {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}
button:disabled {
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button:focus-visible,
a:focus-visible,
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summary:focus-visible,
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a {
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input,
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input[type="range"] {
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}
input[type="checkbox"] {
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}
label {
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  font-size: 12px;
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}
svg {
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}
img {
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main {
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.kicker {
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.intro {
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.intro h1 {
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.panel {
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.primary {
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.grid {
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.muted {
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footer,
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}
.status {
  display: block;
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  margin-top: 10px;
  color: var(--accent);
  font-size: 12px;
}
.sr-only {
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}
[hidden] {
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.data-table {
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.data-table summary {
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.table-scroll {
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.legend {
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.legend i {
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dialog {
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  color: var(--text);
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  padding: 25px;
}
dialog::backdrop {
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}
dialog p {
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.media-credit {
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}
.stage {
  position: relative;
  min-height: 290px;
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  overflow: hidden;
  border: 1px solid var(--line);
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}
@media (max-width: 520px) {
  .intro {
    align-items: flex-start;
    flex-direction: column;
  }
  .grid {
    grid-template-columns: 1fr;
  }
  .panel {
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  .toolbar label {
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  }
  .stage {
    min-height: 270px;
  }
  h1 {
    font-size: 32px;
  }
  .intro p {
    font-size: 12px;
  }
}
@media (prefers-reduced-motion: reduce) {
  *,
  *:before,
  *:after {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
}
html {
  color-scheme: dark;
}
#terrain {
  width: 100%;
  height: 300px;
}
.stage {
  background: linear-gradient(140deg, #112b33, #081b25);
}

(() => {
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    status = (t) => {
      const el = $("#status");
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    clamp = (n, a, b) => Math.max(a, Math.min(b, n));
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  function table(headers, rows) {
    const t = $("#data-table");
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    const caption = document.createElement("caption");
    caption.textContent = "Illustrative sample data";
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    const head = t.createTHead().insertRow();
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      th.scope = "col";
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    draw();
    status("Terrain " + Math.round(offset / 1.4 + 1) + " generated.");
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  draw();
})();