*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --color-primary:    #1B5E20;
  --color-accent:     #4CAF50;
  --color-bg:         #FAFAFA;
  --color-text:       #212121;
  --color-muted:      #616161;
  --color-border:     #E0E0E0;
  --color-surface:    #FFFFFF;
  --color-learn:      #1565C0;
  --color-thpt:       #E65100;
  --color-geo:        #2E7D32;
  --color-labs:       #6A1B9A;
  --radius:           16px;
  --max-w:            1200px;
}

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
}

a { text-decoration: none; color: inherit; }

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

/* ── Header ── */
.platform-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(250, 250, 250, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  padding: 12px 0;
}
.platform-header .container {
  display: flex; align-items: center; gap: 16px;
}
.logo {
  display: flex; align-items: center; gap: 10px; flex-shrink: 0;
}
.logo img { width: 36px; height: 36px; border-radius: 8px; }
.logo-text {
  font-size: 1.1rem; font-weight: 700; color: var(--color-primary);
  letter-spacing: -0.02em;
}
.pillar-nav {
  display: flex; align-items: center; gap: 4px; margin-left: auto;
}
.pillar-nav a {
  padding: 6px 14px; border-radius: 8px; font-size: 0.9rem; font-weight: 500;
  color: var(--color-muted); transition: background 0.15s, color 0.15s;
}
.pillar-nav a:hover { background: #f0f4ff; color: var(--color-text); }

/* ── Hero ── */
.hero {
  padding: 72px 0 56px;
  text-align: center;
}
.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  background: #E8F5E9; color: var(--color-primary);
  font-size: 0.8rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 4px 14px; border-radius: 999px; margin-bottom: 20px;
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800; letter-spacing: -0.03em; color: var(--color-text);
  line-height: 1.15; margin-bottom: 16px;
}
.hero-sub {
  font-size: 1.05rem; color: var(--color-muted); margin-bottom: 36px;
}
.hero-actions {
  display: flex; align-items: center; justify-content: center; gap: 12px; flex-wrap: wrap;
}
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--color-accent); color: #fff;
  font-size: 0.95rem; font-weight: 600; padding: 12px 24px; border-radius: 10px;
  transition: background 0.15s;
}
.btn-primary:hover { background: #388E3C; }
.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px;
  border: 1px solid var(--color-border); background: var(--color-surface);
  color: var(--color-text); font-size: 0.95rem; font-weight: 500;
  padding: 12px 24px; border-radius: 10px; transition: border-color 0.15s;
}
.btn-secondary:hover { border-color: #9E9E9E; }

/* ── Pillars ── */
.pillars-section { padding: 24px 0 64px; }
.section-label {
  font-size: 0.8rem; font-weight: 600; color: var(--color-muted);
  letter-spacing: 0.06em; text-transform: uppercase; margin-bottom: 20px;
}
.pillars {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
}
.pillar-card {
  display: flex; flex-direction: column; gap: 12px;
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius); padding: 24px;
  transition: transform 0.18s, box-shadow 0.18s, border-color 0.18s;
}
.pillar-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.08);
}
.pillar-learn:hover  { border-color: var(--color-learn); }
.pillar-thpt:hover   { border-color: var(--color-thpt); }
.pillar-geo:hover    { border-color: var(--color-geo); }
.pillar-labs:hover   { border-color: var(--color-labs); }

.pillar-icon-wrap {
  width: 44px; height: 44px; border-radius: 10px;
  display: flex; align-items: center; justify-content: center; font-size: 1.4rem;
}
.pillar-learn .pillar-icon-wrap  { background: #E3F2FD; }
.pillar-thpt .pillar-icon-wrap   { background: #FBE9E7; }
.pillar-geo .pillar-icon-wrap    { background: #E8F5E9; }
.pillar-labs .pillar-icon-wrap   { background: #F3E5F5; }

.pillar-card h2 { font-size: 1.05rem; font-weight: 700; }
.pillar-card p  { font-size: 0.875rem; color: var(--color-muted); flex: 1; }

.pillar-cta {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 0.875rem; font-weight: 600; margin-top: 4px;
}
.pillar-learn  .pillar-cta { color: var(--color-learn); }
.pillar-thpt   .pillar-cta { color: var(--color-thpt); }
.pillar-geo    .pillar-cta { color: var(--color-geo); }
.pillar-labs   .pillar-cta { color: var(--color-labs); }

/* ── About ── */
.about-section { padding: 48px 0; border-top: 1px solid var(--color-border); }
.about-inner {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start;
}
.about-section h2 { font-size: 1.3rem; font-weight: 700; margin-bottom: 12px; }
.about-section p  { font-size: 0.925rem; color: var(--color-muted); line-height: 1.7; }
.trust-indicators {
  display: flex; flex-direction: column; gap: 10px; margin-top: 20px;
}
.trust-item {
  display: flex; align-items: center; gap: 10px;
  font-size: 0.875rem; font-weight: 500; color: var(--color-text);
}
.trust-dot {
  width: 8px; height: 8px; border-radius: 999px; background: var(--color-accent); flex-shrink: 0;
}

/* ── Footer ── */
.platform-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 0;
  background: var(--color-surface);
}
.footer-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px; flex-wrap: wrap;
}
.footer-copy { font-size: 0.825rem; color: var(--color-muted); }
.footer-links { display: flex; align-items: center; gap: 20px; flex-wrap: wrap; }
.footer-links a { font-size: 0.825rem; color: var(--color-muted); transition: color 0.15s; }
.footer-links a:hover { color: var(--color-text); }

/* ── Frog hint ── */
.frog-hint-btn {
  position: fixed; bottom: 24px; right: 24px; z-index: 200;
  width: 48px; height: 48px; border-radius: 999px;
  background: var(--color-surface); border: 1px solid var(--color-border);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; transition: box-shadow 0.18s;
  font-size: 1.3rem;
}
.frog-hint-btn:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.18); }
.frog-panel {
  position: fixed; bottom: 84px; right: 24px; z-index: 200;
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius); padding: 16px; width: 240px;
  box-shadow: 0 12px 40px rgba(0,0,0,0.1);
  display: none; flex-direction: column; gap: 8px;
}
.frog-panel.open { display: flex; }
.frog-panel-title { font-size: 0.8rem; font-weight: 600; color: var(--color-muted); margin-bottom: 4px; }
.frog-nav-btn {
  display: flex; align-items: center; gap: 8px;
  padding: 8px 12px; border-radius: 8px; font-size: 0.875rem;
  color: var(--color-text); background: var(--color-bg);
  border: 1px solid var(--color-border); cursor: pointer;
  transition: background 0.15s;
}
.frog-nav-btn:hover { background: #f5f5f5; }

/* ── Responsive ── */
@media (max-width: 900px) {
  .pillars { grid-template-columns: 1fr 1fr; }
  .about-inner { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 600px) {
  .pillars { grid-template-columns: 1fr; }
  .pillar-nav { display: none; }
  .hero { padding: 48px 0 40px; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
}