/* ═══════════════════════════════════════════════════════════════
   STEM Frontiers — site CSS
   Brand: Debiso Best | Red #CC0000 · Black #111111 · White #FFFFFF
   ═══════════════════════════════════════════════════════════════ */

:root {
  --primary:      #CC0000;
  --primary-dark: #990000;
  --primary-light:#FF3333;
  --black:        #111111;
  --surface:      #1A1A1A;
  --surface-2:    #222222;
  --surface-3:    #2A2A2A;
  --border:       #333333;
  --border-light: #444444;
  --text-primary: #F0F0F0;
  --text-muted:   #AAAAAA;
  --text-dim:     #777777;
  --radius:       10px;
  --radius-sm:    6px;
  --shadow:       0 2px 12px rgba(0,0,0,0.5);
  --shadow-lg:    0 8px 32px rgba(0,0,0,0.7);
  --transition:   0.2s ease;
  --max-width:    1100px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--black);
  color: var(--text-primary);
  line-height: 1.6;
}

a { color: var(--primary-light); text-decoration: none; }
a:hover { color: var(--primary); }

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

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

/* ── Top nav ──────────────────────────────────────────────── */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(17,17,17,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav-row {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 24px; max-width: var(--max-width); margin: 0 auto;
}
.brand-link { display: flex; align-items: center; gap: 10px; }
.brand-link img { width: 36px; height: 36px; }
.brand-name { font-weight: 800; font-size: 16px; line-height: 1.1; color: var(--text-primary); }
.brand-sub { font-size: 11px; color: var(--primary); font-weight: 600; letter-spacing: 0.04em; }

.nav-links { display: flex; align-items: center; gap: 26px; }
.nav-links a { color: var(--text-muted); font-weight: 600; font-size: 14px; }
.nav-links a.active, .nav-links a:hover { color: var(--text-primary); }

.nav-cta { display: flex; gap: 10px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 9px 18px; border-radius: var(--radius-sm);
  font-weight: 700; font-size: 13px; border: 1px solid transparent;
  cursor: pointer; transition: var(--transition);
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); color: #fff; }
.btn-outline { border-color: var(--border-light); color: var(--text-primary); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

.nav-toggle { display: none; }

/* ── Hero ─────────────────────────────────────────────────── */
.hero {
  padding: 80px 24px 60px;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, rgba(204,0,0,0.18), transparent 60%);
  border-bottom: 1px solid var(--border);
}
.hero-eyebrow {
  display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: 0.08em;
  color: var(--primary-light); text-transform: uppercase; margin-bottom: 14px;
}
.hero h1 { font-size: clamp(32px, 5vw, 52px); font-weight: 900; line-height: 1.1; margin-bottom: 18px; }
.hero h1 span { color: var(--primary); }
.hero p { max-width: 640px; margin: 0 auto 32px; color: var(--text-muted); font-size: 17px; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn-lg { padding: 14px 28px; font-size: 15px; border-radius: var(--radius); }

/* ── Section scaffolding ──────────────────────────────────── */
.section { padding: 64px 24px; }
.section-alt { background: var(--surface); }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 40px; }
.section-head .eyebrow { color: var(--primary-light); font-weight: 700; font-size: 12px; letter-spacing: 0.08em; text-transform: uppercase; }
.section-head h2 { font-size: clamp(26px, 3.5vw, 36px); font-weight: 800; margin: 8px 0 10px; }
.section-head p { color: var(--text-muted); }

/* ── Card grid ────────────────────────────────────────────── */
.grid { display: grid; gap: 20px; max-width: var(--max-width); margin: 0 auto; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 26px; border-top: 3px solid var(--primary); transition: var(--transition);
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: var(--primary); }
.card-icon { font-size: 26px; margin-bottom: 12px; }
.card h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.card p { color: var(--text-muted); font-size: 14px; }
.card .tag { display: inline-block; margin-top: 12px; font-size: 11px; font-weight: 700; color: var(--primary-light); background: rgba(204,0,0,0.12); padding: 3px 10px; border-radius: 20px; }

/* ── Two-column / portal cards ───────────────────────────── */
.portals { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: var(--max-width); margin: 0 auto; }
.portal-card {
  background: linear-gradient(160deg, var(--surface), var(--surface-2));
  border: 1px solid var(--border); border-radius: var(--radius); padding: 36px;
  text-align: center;
}
.portal-card .card-icon { font-size: 40px; }
.portal-card h3 { font-size: 20px; margin-bottom: 10px; }
.portal-card p { color: var(--text-muted); margin-bottom: 22px; }

/* ── Stats strip ─────────────────────────────────────────── */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; max-width: var(--max-width); margin: 0 auto; text-align: center; }
.stat { padding: 18px; }
.stat-num { font-size: 32px; font-weight: 900; color: var(--primary); }
.stat-label { font-size: 13px; color: var(--text-muted); margin-top: 4px; }

/* ── Footer ──────────────────────────────────────────────── */
.site-footer { border-top: 1px solid var(--border); padding: 40px 24px 28px; }
.footer-row { max-width: var(--max-width); margin: 0 auto; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 24px; }
.footer-brand { display: flex; align-items: center; gap: 10px; }
.footer-brand img { width: 28px; height: 28px; }
.footer-links { display: flex; gap: 22px; flex-wrap: wrap; }
.footer-links a { color: var(--text-muted); font-size: 14px; }
.footer-bottom { max-width: var(--max-width); margin: 24px auto 0; padding-top: 18px; border-top: 1px solid var(--border); font-size: 12px; color: var(--text-dim); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

/* ── Misc page elements ──────────────────────────────────── */
.breadcrumb-bar { padding: 28px 24px; border-bottom: 1px solid var(--border); background: var(--surface); }
.breadcrumb-bar .eyebrow { color: var(--primary-light); font-weight: 700; font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase; }
.breadcrumb-bar h1 { font-size: 28px; font-weight: 800; margin-top: 6px; }

.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; max-width: var(--max-width); margin: 0 auto; }
.contact-info-item { margin-bottom: 22px; }
.contact-info-item .label { font-size: 12px; font-weight: 700; color: var(--primary-light); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 4px; }
.contact-info-item .value { font-size: 15px; }

.form-field { margin-bottom: 16px; }
.form-field label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 6px; color: var(--text-muted); }
.form-field input, .form-field textarea {
  width: 100%; background: var(--surface-2); border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 11px 14px; color: var(--text-primary); font-family: inherit; font-size: 14px;
}
.form-field input:focus, .form-field textarea:focus { outline: none; border-color: var(--primary); }

@media (max-width: 860px) {
  .nav-links { display: none; }
  .grid-2, .grid-3, .grid-4, .portals, .contact-grid, .stats { grid-template-columns: 1fr; }
}