/* ==========================================================================
   RMPC Robotic Servicing Payload Team
   Clean white technical theme with a dark navy hero.
   Plain CSS, no build system, no external dependencies.
   ========================================================================== */

/* ---- Design tokens ------------------------------------------------------ */
:root {
  --navy:        #0b1f3a;   /* hero / footer background */
  --navy-deep:   #071629;
  --ink:         #16202c;   /* body text */
  --ink-soft:    #4a5765;   /* secondary text */
  --accent:      #1565c0;   /* aerospace blue */
  --accent-dark: #0d47a1;
  --line:        #d9e0e8;   /* borders */
  --bg:          #ffffff;
  --bg-alt:      #f5f8fb;   /* alternating section tint */
  --card:        #ffffff;
  --warn-bg:     #fff8e6;
  --warn-line:   #e7c66b;
  --radius:      10px;
  --shadow:      0 1px 3px rgba(11, 31, 58, 0.08), 0 4px 16px rgba(11, 31, 58, 0.05);
  --maxw:        1080px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* ---- Reset / base ------------------------------------------------------- */
* { 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;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { line-height: 1.2; color: var(--navy); font-weight: 700; }
h2 { font-size: 1.9rem; margin: 0 0 0.6rem; }
p { margin: 0 0 1rem; }

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

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

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}
.container.narrow { max-width: 760px; }

/* ---- Skip link (accessibility) ----------------------------------------- */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--navy);
  color: #fff;
  padding: 10px 16px;
  z-index: 1000;
  border-radius: 0 0 var(--radius) 0;
}
.skip-link:focus { left: 0; color: #fff; }

/* ---- Focus visibility --------------------------------------------------- */
a:focus-visible, .btn:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

/* ---- Header / nav ------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: saturate(180%) blur(6px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 60px;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  color: var(--navy);
  text-decoration: none;
  font-size: 0.98rem;
}
.brand-mark { color: var(--accent); font-size: 1.1rem; }
.site-nav { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; }
.site-nav a {
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.92rem;
  font-weight: 500;
}
.site-nav a:hover { color: var(--accent); }
.site-nav .nav-cta {
  background: var(--accent);
  color: #fff;
  padding: 8px 14px;
  border-radius: 8px;
}
.site-nav .nav-cta:hover { background: var(--accent-dark); color: #fff; }

/* ---- Hero --------------------------------------------------------------- */
.hero {
  background:
    radial-gradient(1200px 500px at 80% -10%, rgba(21, 101, 192, 0.35), transparent 60%),
    linear-gradient(160deg, var(--navy) 0%, var(--navy-deep) 100%);
  color: #eef3f9;
  padding: 84px 0 72px;
}
.hero-inner { max-width: 860px; }
.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.75rem;
  font-weight: 600;
  color: #8fb8e8;
  margin: 0 0 18px;
}
.hero h1 {
  color: #ffffff;
  font-size: 2.6rem;
  margin: 0 0 18px;
  letter-spacing: -0.01em;
}
.subhead {
  font-size: 1.25rem;
  color: #cdddf0;
  margin: 0 0 20px;
  font-weight: 500;
}
.hero-copy { color: #b9cbe0; max-width: 720px; margin-bottom: 30px; }

/* ---- Buttons ------------------------------------------------------------ */
.cta-row { display: flex; flex-wrap: wrap; gap: 14px; }
.btn {
  display: inline-block;
  font-weight: 600;
  text-decoration: none;
  padding: 13px 22px;
  border-radius: 8px;
  border: 2px solid transparent;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.05s ease;
  cursor: pointer;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn-primary:hover { background: var(--accent-dark); border-color: var(--accent-dark); color: #fff; }
.btn-ghost { background: transparent; color: #eaf2fb; border-color: rgba(255, 255, 255, 0.5); }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); color: #fff; }
.btn-lg { font-size: 1.05rem; padding: 16px 28px; }

/* ---- Disclaimer banner -------------------------------------------------- */
.disclaimer-banner {
  background: var(--warn-bg);
  border-top: 1px solid var(--warn-line);
  border-bottom: 1px solid var(--warn-line);
  padding: 16px 0;
}
.disclaimer-banner p {
  margin: 0;
  font-size: 0.92rem;
  color: #5a4a17;
}

/* ---- Sections ----------------------------------------------------------- */
.section { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }
.lead { font-size: 1.12rem; color: var(--ink-soft); max-width: 760px; }
.note {
  font-size: 0.9rem;
  color: var(--ink-soft);
  font-style: italic;
  max-width: 760px;
  margin-top: 18px;
}
.note.urgent { font-style: normal; font-weight: 600; color: var(--accent-dark); }

/* ---- Facts grid --------------------------------------------------------- */
.facts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 28px;
}
.fact-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  padding: 18px 20px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.fact-label {
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--accent-dark);
}
.fact-value { font-size: 1.02rem; font-weight: 600; color: var(--ink); }

/* ---- Capability + role grids ------------------------------------------- */
.capability-grid, .role-grid {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
}
.capability-card, .role-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  font-weight: 500;
  box-shadow: var(--shadow);
  position: relative;
  padding-left: 40px;
}
.capability-card::before, .role-card::before {
  content: "▸";
  position: absolute;
  left: 16px;
  color: var(--accent);
  font-weight: 700;
}

/* ---- Check list --------------------------------------------------------- */
.check-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  max-width: 760px;
}
.check-list li {
  position: relative;
  padding: 8px 0 8px 32px;
  border-bottom: 1px solid var(--line);
}
.check-list li::before {
  content: "✓";
  position: absolute;
  left: 4px;
  color: var(--accent);
  font-weight: 700;
}

/* ---- Concept figure ----------------------------------------------------- */
.concept-figure {
  margin: 32px 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--card);
  box-shadow: var(--shadow);
}
.concept-figure figcaption {
  font-size: 0.85rem;
  color: var(--ink-soft);
  font-style: italic;
  padding: 12px 18px;
  background: var(--bg-alt);
  border-top: 1px solid var(--line);
}

/* ---- Timeline ----------------------------------------------------------- */
.timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  border-left: 2px solid var(--line);
  max-width: 820px;
}
.timeline-item {
  position: relative;
  padding: 6px 0 22px 28px;
}
.timeline-item::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 10px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid var(--accent);
}
.timeline-item.is-milestone::before { background: var(--accent); }
.timeline-date {
  display: block;
  font-weight: 700;
  color: var(--navy);
  font-size: 0.95rem;
}
.timeline-item.is-milestone .timeline-date { color: var(--accent-dark); }
.timeline-text { display: block; color: var(--ink-soft); }

/* ---- Join section ------------------------------------------------------- */
.join-section { background: var(--bg-alt); text-align: center; }
.join-section .cta-row { justify-content: center; margin-top: 24px; }
.join-section .lead { margin-left: auto; margin-right: auto; }

/* ---- Footer ------------------------------------------------------------- */
.site-footer {
  background: var(--navy);
  color: #aebfd4;
  padding: 48px 0 40px;
}
.footer-disclaimer { color: #cdd9e8; max-width: 760px; font-size: 0.92rem; }
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 22px 0;
}
.footer-links a { color: #9fc2ec; text-decoration: none; font-size: 0.9rem; }
.footer-links a:hover { color: #fff; text-decoration: underline; }
.footer-meta { font-size: 0.82rem; color: #7e90a8; margin: 0; }

/* ---- Responsive --------------------------------------------------------- */
@media (max-width: 720px) {
  body { font-size: 16px; }
  .hero { padding: 60px 0 50px; }
  .hero h1 { font-size: 2rem; }
  .subhead { font-size: 1.1rem; }
  h2 { font-size: 1.6rem; }
  .section { padding: 48px 0; }
  .site-nav { gap: 12px; }
  .site-nav a:not(.nav-cta) { display: none; } /* keep header clean on small screens */
  .btn { width: 100%; text-align: center; }
  .cta-row { flex-direction: column; }
}

/* ---- Reduced motion ----------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn { transition: none; }
}