/* Fresnel website. Same palette as the app: technical, dense, dark. */

:root {
  --bg: #0e1116;
  --bg-elev: #151a21;
  --bg-elev-2: #1b222b;
  --border: #262f3a;
  --border-strong: #34404e;
  --text: #d7dee7;
  --text-strong: #f2f5f8;
  --muted: #8a95a3;
  --accent: #3fa3ff;
  --accent-strong: #1f8bf0;
  --accent-soft: rgba(63, 163, 255, 0.14);
  --ok: #3ccf8e;
  --warn: #f0b429;
  --bad: #f25f5c;
  --radius: 8px;
  --font-ui: "Inter", "Segoe UI", "Cantarell", "Ubuntu", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "Cascadia Mono", "Fira Code", "Ubuntu Mono", Consolas, ui-monospace, monospace;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 72px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 var(--font-ui);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
code { font: 0.9em var(--font-mono); background: var(--bg-elev-2); padding: 1px 5px; border-radius: 4px; }
h1, h2, h3 { color: var(--text-strong); line-height: 1.2; margin: 0; }
h1 { font-size: clamp(32px, 5vw, 52px); letter-spacing: -0.02em; font-weight: 700; }
h2 { font-size: clamp(26px, 3.4vw, 36px); letter-spacing: -0.01em; font-weight: 700; }
h3 { font-size: 17px; font-weight: 600; }
p { margin: 0; }

.wrap { width: min(1160px, 100% - 32px); margin: 0 auto; }
.skip { position: absolute; left: -999px; top: 8px; background: var(--accent); color: #000; padding: 6px 10px; border-radius: 4px; z-index: 20; }
.skip:focus { left: 8px; }
.muted { color: var(--muted); }

/* ---- Nav ---- */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 60px; gap: 16px; }
.brand { color: var(--text-strong); font-weight: 700; font-size: 18px; display: flex; align-items: center; gap: 8px; }
.brand:hover { text-decoration: none; }
.brand-mark { color: var(--accent); }
.nav nav { display: flex; gap: 22px; font-size: 14px; }
.nav nav a { color: var(--muted); }
.nav nav a:hover { color: var(--text-strong); text-decoration: none; }
@media (max-width: 720px) {
  .nav nav a:not(:last-child):not([href="#download"]) { display: none; }
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 10px 18px; border-radius: var(--radius);
  border: 1px solid var(--border-strong); background: var(--bg-elev-2);
  color: var(--text-strong); font-weight: 600; font-size: 15px;
}
.btn:hover { text-decoration: none; border-color: var(--muted); }
.btn-primary { background: var(--accent-strong); border-color: var(--accent-strong); color: #fff; }
.btn-primary:hover { background: var(--accent); border-color: var(--accent); }
.btn:focus-visible, a:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---- Hero ---- */
.hero {
  padding: 72px 0 64px;
  background:
    radial-gradient(900px 420px at 85% 10%, rgba(63, 163, 255, 0.12), transparent 70%),
    radial-gradient(700px 360px at 10% 90%, rgba(60, 207, 142, 0.07), transparent 70%);
}
.hero-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: center; }
.eyebrow { color: var(--accent); font: 600 13px var(--font-mono); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 14px; }
.lede { font-size: 18px; color: var(--text); margin-top: 18px; max-width: 34em; }
.cta-row { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 28px; }
.hero-meta { margin-top: 16px; font-size: 14px; color: var(--muted); }
@media (max-width: 900px) {
  .hero { padding-top: 48px; }
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
}

/* ---- App window illustrations ---- */
.hero-visual, .mtr { margin: 0; }
.window {
  background: var(--bg-elev); border: 1px solid var(--border-strong); border-radius: 10px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.45); overflow: hidden;
}
.window-bar { display: flex; align-items: center; gap: 6px; padding: 9px 12px; border-bottom: 1px solid var(--border); background: var(--bg-elev-2); }
.window-bar span { width: 10px; height: 10px; border-radius: 50%; background: var(--border-strong); }
.window-bar em { font: 12px var(--font-mono); font-style: normal; color: var(--muted); margin-left: 8px; }
.plan { display: block; width: 100%; height: auto; background: #f4f5f7; }
.plan-floor { fill: #ffffff; stroke: #c9ced6; stroke-width: 2; }
.plan-walls path { fill: none; stroke: #4a5361; stroke-width: 4; stroke-linecap: square; }
.plan-points circle { fill: #1f6fd1; stroke: #fff; stroke-width: 2; }
.plan-aps rect { fill: #0e1116; stroke: #fff; stroke-width: 2; }
.plan-aps text { font: 600 12px var(--font-ui); fill: #0e1116; paint-order: stroke; stroke: #fff; stroke-width: 3px; }
.legend { display: flex; gap: 14px; flex-wrap: wrap; padding: 10px 12px; font: 12px var(--font-mono); color: var(--muted); }
.legend i { display: inline-block; width: 10px; height: 10px; border-radius: 2px; margin-right: 6px; vertical-align: -1px; }
figcaption { font-size: 12px; color: var(--muted); text-align: right; margin-top: 8px; }
.mtr figcaption { padding: 0 12px 10px; }

/* ---- Principles ---- */
.principles { border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); background: var(--bg-elev); }
.principles-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.principles-grid > div { padding: 26px 22px; border-left: 1px solid var(--border); }
.principles-grid > div:first-child { border-left: 0; padding-left: 0; }
.principles-grid strong { color: var(--text-strong); display: block; margin-bottom: 6px; }
.principles-grid p { font-size: 14px; color: var(--muted); }
@media (max-width: 900px) {
  .principles-grid { grid-template-columns: 1fr 1fr; }
  .principles-grid > div { padding: 20px 16px; border-left: 0; }
  .principles-grid > div:first-child { padding-left: 16px; }
}
@media (max-width: 520px) { .principles-grid { grid-template-columns: 1fr; } }

/* ---- Sections ---- */
.section { padding: 84px 0; }
.section-alt { background: var(--bg-elev); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-lede { color: var(--muted); font-size: 17px; margin-top: 10px; max-width: 40em; }

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 40px; }
.feature { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; }
.feature p { font-size: 15px; color: var(--muted); margin-top: 8px; }
.icon { width: 38px; height: 38px; border-radius: 8px; background: var(--accent-soft); display: grid; place-items: center; margin-bottom: 14px; }
.icon svg { width: 20px; height: 20px; fill: none; stroke: var(--accent); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
@media (max-width: 900px) { .feature-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .feature-grid { grid-template-columns: 1fr; } }

.steps { list-style: none; padding: 0; margin: 40px 0 0; display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; counter-reset: step; }
.steps li { display: flex; flex-direction: column; gap: 12px; padding: 20px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--bg); }
.steps p { font-size: 14px; color: var(--muted); margin-top: 6px; }
.step-n { width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--accent); color: var(--accent); display: grid; place-items: center; font: 600 14px var(--font-mono); }
@media (max-width: 1000px) { .steps { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .steps { grid-template-columns: 1fr; } .steps li { flex-direction: row; } }

.tools-grid { display: grid; grid-template-columns: 1fr 1.1fr; gap: 48px; align-items: center; }
.tool-list { list-style: none; padding: 0; margin: 28px 0 0; display: flex; flex-direction: column; gap: 12px; }
.tool-list li { color: var(--muted); font-size: 15px; padding-left: 16px; border-left: 2px solid var(--border-strong); }
.tool-list strong { color: var(--text-strong); display: block; }
.note { margin-top: 20px; font-size: 14px; color: var(--muted); }
.mtr table { width: 100%; border-collapse: collapse; font: 13px var(--font-mono); }
.mtr th { text-align: left; font: 600 11px var(--font-ui); text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); padding: 10px 12px; border-bottom: 1px solid var(--border); }
.mtr td { padding: 8px 12px; border-bottom: 1px solid var(--border); white-space: nowrap; }
.mtr td.dim { color: var(--muted); }
.mtr td.bad { color: var(--bad); }
.mtr .window-bar + table { margin: 0; }
@media (max-width: 900px) {
  .tools-grid { grid-template-columns: 1fr; }
  .mtr { overflow-x: auto; }
}

/* ---- Download ---- */
.release-note { margin-top: 18px; padding: 12px 16px; border: 1px solid color-mix(in srgb, var(--warn) 50%, transparent); background: color-mix(in srgb, var(--warn) 10%, transparent); border-radius: var(--radius); font-size: 14px; }
.download-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 32px; }
.download { display: flex; flex-direction: column; gap: 10px; padding: 24px; background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); }
.download.recommended { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent) inset; }
.download .btn { align-self: flex-start; margin-top: 6px; }
.asset-meta { font: 12px var(--font-mono); color: var(--muted); min-height: 1.2em; }
.small-list { margin: 6px 0 0; padding-left: 18px; font-size: 14px; color: var(--muted); display: flex; flex-direction: column; gap: 6px; }
.badge { display: inline-block; margin-left: 8px; padding: 1px 8px; border-radius: 10px; font: 600 11px var(--font-ui); background: var(--accent-soft); color: var(--accent); vertical-align: 2px; }
.checksums { margin-top: 24px; font-size: 14px; color: var(--muted); }
@media (max-width: 900px) { .download-grid { grid-template-columns: 1fr; } }

/* ---- FAQ ---- */
.faq { margin-top: 32px; display: flex; flex-direction: column; gap: 10px; max-width: 820px; }
.faq details { border: 1px solid var(--border); border-radius: var(--radius); background: var(--bg-elev); padding: 0 18px; }
.faq summary { cursor: pointer; padding: 16px 0; color: var(--text-strong); font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--muted); font: 18px var(--font-mono); }
.faq details[open] summary::after { content: "−"; }
.faq details p { padding: 0 0 16px; color: var(--muted); font-size: 15px; }

/* ---- Footer ---- */
.footer { border-top: 1px solid var(--border); padding: 28px 0; font-size: 14px; color: var(--muted); }
.footer-inner { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }