/* A.I. Holding GmbH — ai-holding.com
   Restrained, precise, legible. Conversion-first, no trading-floor clichés. */

:root {
  --ink: #0b1f33;
  --ink-soft: #33475c;
  --muted: #66798c;
  --line: #e2e8f0;
  --bg: #ffffff;
  --bg-soft: #f6f8fb;
  --accent: #1f6feb;
  --accent-ink: #0b3d91;
  --radius: 14px;
  --maxw: 1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-ink); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 20;
  background: rgba(255,255,255,.9);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--ink); }
.brand:hover { text-decoration: none; }
.brand .mark {
  width: 32px; height: 32px; border-radius: 8px;
  background: var(--ink); color: #fff;
  display: grid; place-items: center;
  font-weight: 700; font-size: 13px; letter-spacing: .04em;
}
.brand .name { font-weight: 650; letter-spacing: -.01em; }
.brand .name span { color: var(--muted); font-weight: 500; }

.nav { display: flex; align-items: center; gap: 28px; }
.nav a { color: var(--ink-soft); font-size: 15px; }
.nav a:hover { color: var(--ink); text-decoration: none; }
.nav .btn { margin-left: 4px; }

.btn {
  display: inline-block; padding: 11px 20px; border-radius: 999px;
  font-size: 15px; font-weight: 550; border: 1px solid transparent;
  transition: .15s ease; white-space: nowrap;
}
.btn-primary { background: var(--ink); color: #fff; }
.btn-primary:hover { background: #14304d; text-decoration: none; }
.btn-ghost { border-color: var(--line); color: var(--ink); }
.btn-ghost:hover { border-color: var(--ink); text-decoration: none; }
.btn-light { background: #fff; color: var(--ink); }
.btn-light:hover { background: #eef4ff; text-decoration: none; }
.btn-lg { padding: 14px 26px; font-size: 16px; }

.textlink { color: var(--ink-soft); font-size: 15px; font-weight: 550; padding: 14px 0; }
.textlink:hover { color: var(--ink); text-decoration: none; }

/* ---------- hero ---------- */
.hero { padding: 92px 0 64px; }
.hero .eyebrow { display: inline-block; font-size: 13px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; color: var(--accent); margin-bottom: 20px; }
.hero h1 { font-size: clamp(34px, 5vw, 54px); line-height: 1.08; letter-spacing: -.025em; margin: 0 0 22px; max-width: 17ch; }
.hero .lead { font-size: clamp(17px, 2vw, 20px); color: var(--ink-soft); max-width: 62ch; margin: 0 0 32px; }
.hero .actions { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 22px; }
.hero .trust { margin: 22px 0 0; font-size: 14px; color: var(--muted); }

/* ---------- trust bar ---------- */
.trustbar { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--bg-soft); }
.trustbar .wrap { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; padding-top: 22px; padding-bottom: 22px; }
.tb-item strong { display: block; font-size: 15px; color: var(--ink); }
.tb-item span { font-size: 13.5px; color: var(--muted); }

/* ---------- sections ---------- */
section { padding: 72px 0; }
section.soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 62ch; margin-bottom: 40px; }
.section-head h2 { font-size: clamp(24px, 3.2vw, 34px); letter-spacing: -.02em; line-height: 1.15; margin: 0 0 14px; }
.section-head p { color: var(--ink-soft); font-size: 17px; margin: 0; }

/* pain list */
.pains { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.pains li { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 24px; font-size: 15px; color: var(--ink-soft); }
.pains li strong { display: block; color: var(--ink); margin-bottom: 6px; }

/* process */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.step { border-top: 2px solid var(--ink); padding-top: 18px; }
.step .n { font-size: 13px; font-weight: 700; color: var(--accent); letter-spacing: .05em; }
.step h3 { font-size: 17px; margin: 8px 0 8px; letter-spacing: -.01em; }
.step p { font-size: 14.5px; color: var(--ink-soft); margin: 0; }

.principle { margin-top: 44px; padding: 26px 28px; border-left: 3px solid var(--accent); background: #fff; border-radius: 0 var(--radius) var(--radius) 0; font-size: 18px; color: var(--ink); }
.principle span { display: block; margin-top: 8px; font-size: 14px; color: var(--muted); }

/* services */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 28px 26px; display: flex; flex-direction: column; }
.card .tag { align-self: flex-start; font-size: 12.5px; font-weight: 600; color: var(--accent-ink); background: #eef4ff; border: 1px solid #dbe7ff; padding: 4px 10px; border-radius: 999px; margin-bottom: 16px; }
.card h3 { font-size: 19px; margin: 0 0 10px; letter-spacing: -.01em; }
.card p { font-size: 15px; color: var(--ink-soft); margin: 0; }
.card .out { margin-top: auto; padding-top: 16px; font-size: 14px; color: var(--muted); }

/* coverage */
.coverage { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px 32px; }
.coverage li { position: relative; padding-left: 28px; font-size: 15.5px; color: var(--ink-soft); }
.coverage li::before { content: "✓"; position: absolute; left: 0; top: 0; color: var(--accent); font-weight: 700; }

/* about */
.about { display: grid; grid-template-columns: 1.4fr 1fr; gap: 48px; align-items: start; }
.about p { color: var(--ink-soft); font-size: 16.5px; }
.about p:first-child { margin-top: 0; }
.cred { list-style: none; padding: 0; margin: 0; }
.cred li { padding: 16px 0; border-bottom: 1px solid var(--line); font-size: 15px; }
.cred li:first-child { border-top: 1px solid var(--line); }
.cred strong { display: block; color: var(--ink); font-weight: 600; }
.cred span { color: var(--muted); font-size: 14px; }

/* faq */
.faq { display: grid; gap: 0; border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; padding: 20px 0; font-size: 16.5px; font-weight: 550; color: var(--ink); list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--accent); font-size: 22px; font-weight: 400; line-height: 1; }
.faq details[open] summary::after { content: "–"; }
.faq details p { margin: 0 0 22px; color: var(--ink-soft); font-size: 15.5px; max-width: 70ch; }

/* cta band */
.cta-band { background: var(--ink); color: #fff; text-align: center; }
.cta-band h2 { font-size: clamp(24px, 3.2vw, 34px); letter-spacing: -.02em; margin: 0 auto 14px; max-width: 24ch; }
.cta-band p { color: #c9d6e4; max-width: 56ch; margin: 0 auto 30px; font-size: 17px; }
.cta-band .loc { margin-top: 22px; color: #9fb3c8; font-size: 14.5px; }
.cta-band .loc a { color: #c9d6e4; }

/* footer */
.site-footer { border-top: 1px solid var(--line); padding: 34px 0; font-size: 14px; color: var(--muted); background: var(--bg-soft); }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; align-items: center; }
.site-footer nav a { color: var(--ink-soft); margin-left: 18px; }
.site-footer nav a:first-child { margin-left: 0; }

/* legal pages */
.legal { padding: 56px 0 80px; }
.legal h1 { font-size: clamp(26px, 3.5vw, 36px); letter-spacing: -.02em; margin: 0 0 8px; }
.legal .sub { color: var(--muted); margin: 0 0 40px; }
.legal h2 { font-size: 19px; margin: 38px 0 10px; letter-spacing: -.01em; }
.legal p, .legal li { color: var(--ink-soft); font-size: 15.5px; }
.legal dl { display: grid; grid-template-columns: 240px 1fr; gap: 6px 20px; margin: 18px 0; }
.legal dt { color: var(--muted); }
.legal dd { margin: 0; color: var(--ink); }
.back { display: inline-block; margin-bottom: 28px; font-size: 14px; color: var(--muted); }

@media (max-width: 900px) {
  .trustbar .wrap { grid-template-columns: repeat(2, 1fr); gap: 16px 24px; }
  .pains, .steps { grid-template-columns: repeat(2, 1fr); }
  .cards { grid-template-columns: 1fr; }
  .about { grid-template-columns: 1fr; gap: 32px; }
  .coverage { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  .nav { gap: 16px; }
  .nav a:not(.btn) { display: none; }
  .trustbar .wrap { grid-template-columns: 1fr; }
  .pains, .steps { grid-template-columns: 1fr; }
  section { padding: 56px 0; }
  .hero { padding: 64px 0 48px; }
  .legal dl { grid-template-columns: 1fr; gap: 2px; }
  .legal dd { margin-bottom: 12px; }
}