:root {
  --bg: #0d1117;
  --card: #161b22;
  --line: #30363d;
  --ink: #f0f6fc;
  --mut: #8b949e;
  --acc: #58a6ff;
  --ok: #7ee787;
  --bad: #ff7b72;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--acc); text-decoration: none; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 16px; }
header.nav { display: flex; align-items: center; justify-content: space-between; padding: 18px 0; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; color: var(--ink); }
.logo img { width: 28px; height: 28px; }
.btn {
  display: inline-block; padding: 12px 22px; border-radius: 10px; font-weight: 600;
  background: var(--acc); color: #04122a; border: 1px solid var(--acc); cursor: pointer; font-size: 16px;
}
.btn:hover { filter: brightness(1.1); }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.hero {
  background: linear-gradient(180deg, rgba(13,17,23,.55), var(--bg)), url("/img/bg-grid.webp") center/cover no-repeat;
  border-bottom: 1px solid var(--line);
}
.hero .inner { padding: 64px 0 56px; text-align: center; }
.eyebrow { color: var(--acc); font-weight: 600; letter-spacing: .08em; text-transform: uppercase; font-size: 13px; }
h1 { font-size: clamp(32px, 6vw, 56px); line-height: 1.1; margin: 12px auto 16px; max-width: 800px; }
.lead { color: #c9d1d9; max-width: 640px; margin: 0 auto 28px; font-size: 18px; }
.cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.diagram { margin: 44px auto 0; max-width: 840px; border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.diagram img { display: block; width: 100%; height: auto; }
section { padding: 64px 0; }
h2 { font-size: clamp(24px, 4vw, 34px); margin: 0 0 8px; }
.sub { color: var(--mut); margin: 0 0 32px; max-width: 640px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.chip { border: 1px solid var(--line); background: var(--card); border-radius: 999px; padding: 4px 12px; font-size: 14px; color: #c9d1d9; }
.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 20px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--mut); font-size: 15px; }
.step-n { color: var(--acc); font-weight: 700; font-size: 13px; letter-spacing: .08em; }
.band { background: var(--card); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.final { text-align: center; }
footer { padding: 32px 0 48px; color: var(--mut); font-size: 14px; border-top: 1px solid var(--line); }
form { display: grid; gap: 16px; }
.row { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
label { display: grid; gap: 6px; font-size: 14px; color: #c9d1d9; font-weight: 600; }
input, select, textarea {
  width: 100%; background: var(--bg); color: var(--ink); border: 1px solid var(--line);
  border-radius: 8px; padding: 10px 12px; font: inherit; font-weight: 400;
}
input:focus, select:focus, textarea:focus { outline: 2px solid var(--acc); outline-offset: 1px; }
.hp { position: absolute; left: -9999px; height: 0; overflow: hidden; }
.msg { padding: 12px 14px; border-radius: 8px; border: 1px solid var(--line); display: none; }
.msg.ok { display: block; border-color: var(--ok); color: var(--ok); }
.msg.err { display: block; border-color: var(--bad); color: var(--bad); }
.form-card { max-width: 720px; margin: 24px auto 0; }