/* ===========================================================
   OrbitRelay — CubeSat technical site
   Clean / technical aesthetic
   =========================================================== */

:root {
  --bg:        #f7f8fa;
  --surface:   #ffffff;
  --ink:       #131720;
  --ink-soft:  #4a5365;
  --line:      #e2e6ee;
  --line-2:    #cdd4e0;
  --accent:    #0b5fff;
  --accent-2:  #00b3a4;
  --warn:      #e8623d;
  --grid:      #eef1f6;
  --mono: "SFMono-Regular", ui-monospace, "JetBrains Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
  --maxw: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background:
    linear-gradient(var(--grid) 1px, transparent 1px) 0 0 / 100% 56px,
    var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

/* ---------- Header / nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.88);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav {
  display: flex; align-items: center; gap: 8px;
  max-width: var(--maxw); margin: 0 auto; padding: 12px 24px;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; letter-spacing: -0.02em; font-size: 18px;
  color: var(--ink); margin-right: auto;
}
.brand:hover { text-decoration: none; }
.brand .logo {
  width: 26px; height: 26px; display: inline-block;
}
.brand small {
  font-family: var(--mono); font-weight: 500; font-size: 10px;
  color: var(--ink-soft); letter-spacing: 0.06em; text-transform: uppercase;
}
.nav-links { display: flex; flex-wrap: wrap; gap: 2px; }
.nav-links a {
  font-size: 14px; color: var(--ink-soft); padding: 6px 11px;
  border-radius: 6px; font-weight: 500;
}
.nav-links a:hover { background: var(--grid); color: var(--ink); text-decoration: none; }
.nav-links a.active { color: var(--accent); background: #eaf1ff; }
.nav-toggle { display:none; }

/* ---------- Hero ---------- */
.hero { padding: 72px 0 48px; }
.eyebrow {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent); font-weight: 600;
}
.hero h1 {
  font-size: clamp(32px, 5vw, 52px); line-height: 1.05;
  letter-spacing: -0.03em; margin: 14px 0 18px; max-width: 18ch;
}
.hero p.lead {
  font-size: 19px; color: var(--ink-soft); max-width: 62ch; margin: 0 0 28px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-weight: 600; font-size: 15px; padding: 11px 18px;
  border-radius: 8px; border: 1px solid transparent;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: #094ad1; text-decoration: none; }
.btn-ghost { border-color: var(--line-2); color: var(--ink); background: var(--surface); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.btn-row { display: flex; gap: 12px; flex-wrap: wrap; }

/* ---------- Sections ---------- */
section { padding: 14px 0; }
.section-head { margin: 40px 0 22px; }
.section-head .eyebrow { display: block; margin-bottom: 8px; }
.section-head h2 {
  font-size: clamp(24px, 3.4vw, 34px); letter-spacing: -0.02em; margin: 0;
}
.section-head p { color: var(--ink-soft); max-width: 64ch; margin: 10px 0 0; }

h3 { font-size: 20px; letter-spacing: -0.01em; margin: 28px 0 8px; }
p { margin: 0 0 16px; }

/* ---------- Cards / grid ---------- */
.grid { display: grid; gap: 18px; }
.grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid.cols-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: 12px; padding: 22px;
}
.card h3 { margin-top: 0; }
.card .kicker {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--accent-2); font-weight: 600;
}
.card p:last-child { margin-bottom: 0; }

/* ---------- Stat blocks ---------- */
.stat {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: 12px; padding: 20px;
}
.stat .num {
  font-family: var(--mono); font-size: 30px; font-weight: 700;
  letter-spacing: -0.02em; color: var(--ink); line-height: 1;
}
.stat .lbl { color: var(--ink-soft); font-size: 13px; margin-top: 8px; }

/* ---------- Spec table ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 12px; }
table.spec { width: 100%; border-collapse: collapse; background: var(--surface); font-size: 14px; }
table.spec th, table.spec td { text-align: left; padding: 12px 16px; border-bottom: 1px solid var(--line); }
table.spec thead th {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--ink-soft); background: #f2f5fa;
}
table.spec tbody tr:last-child td { border-bottom: none; }
table.spec td.mono, table.spec td:not(:first-child) { font-family: var(--mono); color: var(--ink-soft); }
table.spec td:first-child { font-weight: 600; color: var(--ink); }

/* ---------- Callout ---------- */
.callout {
  border-left: 3px solid var(--accent); background: #eef4ff;
  padding: 16px 20px; border-radius: 0 10px 10px 0; margin: 22px 0;
  color: #1d3a78;
}
.callout.warn { border-color: var(--warn); background: #fdf0eb; color: #8a3318; }
.callout strong { color: inherit; }

/* ---------- Figure ---------- */
figure { margin: 26px 0; }
figure svg { width: 100%; height: auto; display: block; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); }
figcaption { font-size: 13px; color: var(--ink-soft); margin-top: 10px; font-family: var(--mono); }

/* ---------- Steps ---------- */
.steps { counter-reset: step; display: grid; gap: 14px; margin: 20px 0; }
.step {
  position: relative; background: var(--surface); border: 1px solid var(--line);
  border-radius: 10px; padding: 18px 18px 18px 60px;
}
.step::before {
  counter-increment: step; content: counter(step);
  position: absolute; left: 16px; top: 16px;
  width: 30px; height: 30px; border-radius: 8px;
  background: var(--accent); color: #fff; font-family: var(--mono);
  font-weight: 700; display: grid; place-items: center; font-size: 14px;
}
.step h4 { margin: 0 0 4px; font-size: 16px; }
.step p { margin: 0; color: var(--ink-soft); font-size: 14px; }

/* ---------- Tag / pill ---------- */
.tag {
  display: inline-block; font-family: var(--mono); font-size: 11px;
  letter-spacing: 0.05em; text-transform: uppercase; color: var(--ink-soft);
  border: 1px solid var(--line-2); border-radius: 999px; padding: 3px 10px;
  margin: 0 6px 6px 0;
}

/* ---------- Footer ---------- */
.site-footer {
  margin-top: 64px; border-top: 1px solid var(--line);
  background: var(--surface);
}
.site-footer .wrap { padding-top: 36px; padding-bottom: 36px; }
.foot-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 28px; }
.site-footer h5 { font-size: 12px; font-family: var(--mono); text-transform: uppercase; letter-spacing: 0.08em; color: var(--ink-soft); margin: 0 0 12px; }
.site-footer a { display: block; color: var(--ink-soft); font-size: 14px; padding: 3px 0; }
.site-footer a:hover { color: var(--accent); }
.foot-bottom { margin-top: 28px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 12px; color: var(--ink-soft); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
.sources { font-size: 12.5px; color: var(--ink-soft); }
.sources a { display: inline; }

/* ---------- Disclaimer ---------- */
.concept-banner {
  background: #fff8e6; border: 1px solid #f0d98a; color: #7a5b00;
  border-radius: 10px; padding: 12px 16px; font-size: 13.5px; margin: 0 0 24px;
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .grid.cols-3, .grid.cols-4 { grid-template-columns: repeat(2, 1fr); }
  .foot-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
  .grid.cols-2, .grid.cols-3, .grid.cols-4 { grid-template-columns: 1fr; }
  .nav-links { display: none; width: 100%; flex-direction: column; }
  .nav-links.open { display: flex; }
  .nav-toggle {
    display: inline-flex; margin-left: auto; background: var(--surface);
    border: 1px solid var(--line-2); border-radius: 8px; padding: 6px 12px;
    font-family: var(--mono); font-size: 13px; cursor: pointer;
  }
  .nav { flex-wrap: wrap; }
  .foot-grid { grid-template-columns: 1fr; }
}