/* IFS Aachen – infrared fiber sensors
   Plain CSS, no external fonts or scripts (nothing loaded from third parties). */

:root {
  --red: #d40000;
  --red-dark: #a30000;
  --ink: #1a1a1a;
  --text: #333;
  --muted: #666;
  --line: #e2e2e2;
  --bg: #ffffff;
  --bg-soft: #f6f6f4;
  --max: 1080px;
  --radius: 6px;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color-scheme: light;
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-size: 1.0625rem;
  line-height: 1.65;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--red-dark); }
a:hover { color: var(--red); }

h1, h2, h3 { color: var(--ink); line-height: 1.25; margin: 0 0 .6em; }
h1 { font-size: clamp(1.8rem, 4vw, 2.6rem); letter-spacing: -.01em; }
h2 { font-size: clamp(1.35rem, 2.6vw, 1.75rem); margin-top: 2.2em; }
h3 { font-size: 1.15rem; margin-top: 1.8em; }
p { margin: 0 0 1em; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }

.skip { position: absolute; left: -9999px; }
.skip:focus { left: 12px; top: 12px; background: #fff; padding: 8px 12px; z-index: 10; }

/* ---------- Header ---------- */
.site-header {
  border-bottom: 1px solid var(--line);
  background: #fff;
  position: sticky; top: 0; z-index: 5;
}
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px; min-height: 72px;
}
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; color: var(--ink); }
.brand img { width: 96px; }
.brand span { font-weight: 600; font-size: .95rem; color: var(--muted); }

.nav ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 4px; }
.nav a {
  display: block; padding: 8px 12px; border-radius: var(--radius);
  text-decoration: none; color: var(--ink); font-weight: 500;
}
.nav a:hover { background: var(--bg-soft); color: var(--red-dark); }
.nav a[aria-current="page"] { color: var(--red); }

.nav-toggle { display: none; }

@media (max-width: 760px) {
  .brand span { display: none; }
  .nav-toggle {
    display: inline-flex; align-items: center; gap: 6px;
    background: none; border: 1px solid var(--line); border-radius: var(--radius);
    padding: 8px 12px; font: inherit; color: var(--ink); cursor: pointer;
  }
  .nav { display: none; position: absolute; left: 0; right: 0; top: 100%;
         background: #fff; border-bottom: 1px solid var(--line); }
  .nav.open { display: block; }
  .nav ul { flex-direction: column; padding: 8px 12px 12px; }
}

/* ---------- Hero ---------- */
.hero { background: var(--bg-soft); border-bottom: 1px solid var(--line); }
.hero .wrap {
  display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: center;
  padding-top: 56px; padding-bottom: 56px;
}
.hero .eyebrow { color: var(--red); font-weight: 700; text-transform: uppercase;
                 letter-spacing: .08em; font-size: .8rem; margin-bottom: .6em; }
.hero p.lead { font-size: 1.2rem; color: var(--text); }
.hero-img { border-radius: var(--radius); overflow: hidden; box-shadow: 0 8px 28px rgba(0,0,0,.12); }
.hero-img img { width: 100%; }
@media (max-width: 760px) {
  .hero .wrap { grid-template-columns: 1fr; padding-top: 36px; padding-bottom: 36px; }
}

.btn {
  display: inline-block; background: var(--red); color: #fff; text-decoration: none;
  padding: 11px 20px; border-radius: var(--radius); font-weight: 600; margin: 4px 8px 4px 0;
}
.btn:hover { background: var(--red-dark); color: #fff; }
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid #bbb; }
.btn.ghost:hover { border-color: var(--ink); color: var(--ink); }

/* ---------- Page layout ---------- */
.page-head { background: var(--bg-soft); border-bottom: 1px solid var(--line); padding: 40px 0 28px; }
.page-head h1 { margin: 0; }
.page-head p { margin: .5em 0 0; color: var(--muted); max-width: 60ch; }

main { padding-bottom: 64px; }
main .content > :first-child { margin-top: 1.6em; }

.prose { max-width: 72ch; }
.wrap.prose { max-width: var(--max); }
.wrap.prose > * { max-width: 72ch; }

/* Two-column block: text + images */
.split {
  display: grid; grid-template-columns: 1fr 1fr; gap: 32px; align-items: start;
  padding: 28px 0; border-bottom: 1px solid var(--line);
}
.split:last-child { border-bottom: 0; }
.split h2 { margin-top: 0; }
@media (max-width: 760px) { .split { grid-template-columns: 1fr; } }

.gallery { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 14px; }
.gallery.single { grid-template-columns: 1fr; }

figure { margin: 0; }
figure a { display: block; border-radius: var(--radius); overflow: hidden;
           border: 1px solid var(--line); background: #fff; }
figure img { margin: 0 auto; }
figcaption { font-size: .88rem; color: var(--muted); margin-top: 6px; }

ul.specs { padding-left: 1.2em; margin: 0 0 1em; }
ul.specs li { margin: .25em 0; }
ul.specs li::marker { color: var(--red); }

/* Features table */
.table-wrap { overflow-x: auto; margin: 1em 0 2em; }
table { border-collapse: collapse; width: 100%; font-size: .97rem; }
th, td { text-align: left; vertical-align: top; padding: 10px 14px; border-bottom: 1px solid var(--line); }
th { background: var(--bg-soft); color: var(--ink); }
td:first-child { font-weight: 600; color: var(--ink); width: 38%; }

/* Cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 18px; margin: 1.2em 0; }
.card { border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; background: #fff; }
.card h3 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }

.tags { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 1em 0; }
.tags li { background: var(--bg-soft); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; font-size: .92rem; }

/* Contact box */
.contact-box {
  border-left: 4px solid var(--red); background: var(--bg-soft);
  padding: 20px 24px; border-radius: 0 var(--radius) var(--radius) 0; margin: 1.5em 0;
}
.contact-box p { margin: .2em 0; }
dl.contact { display: grid; grid-template-columns: max-content 1fr; gap: 6px 18px; margin: 0; }
dl.contact dt { font-weight: 600; color: var(--ink); }
dl.contact dd { margin: 0; }

/* CTA band */
.cta { background: var(--ink); color: #eee; padding: 44px 0; }
.cta h2 { color: #fff; margin-top: 0; }
.cta a.btn.ghost { color: #fff; border-color: #777; }
.cta a.btn.ghost:hover { border-color: #fff; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); padding: 28px 0; font-size: .92rem; color: var(--muted); }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
.site-footer a { color: var(--muted); }
.site-footer nav a { margin-left: 16px; }
.site-footer nav a:first-child { margin-left: 0; }