:root {
  --bg: #0d1117;
  --text: #e6edf3;
  --card: #161b22;
  --accent: #2f81f7;
  --muted: #8b949e;
  --border: #30363d;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  margin: 0;
  line-height: 1.6;
}

.container {
  max-width: 900px;
  margin: auto;
  padding: 2rem;
}

/* HEADER & LOGO */
header {
  display: flex;
  align-items: center;
  gap: 15px;
  padding: 40px 0;
  justify-content: center;
}
.logo-svg {
  width: 42px;
  height: 42px;
}
.brand-name {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: #fff;
}
.pulse-anim {
  animation: pulse-fade 2s infinite;
}
@keyframes pulse-fade {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.3;
  }
}

/* HERO SECTION */
.hero {
  text-align: center;
  padding: 40px 0 80px 0;
}
h1 {
  font-size: 3.5rem;
  letter-spacing: -0.05em;
  margin: 0;
  color: #fff;
  line-height: 1.1;
}
.accent-text {
  color: var(--accent);
}
.lead {
  color: var(--muted);
  font-size: 1.25rem;
  margin-top: 1.5rem;
}

/* FEATURE BLOCKS & DIAGRAMS */
h2 {
  font-size: 1.4rem;
  margin-top: 4rem;
  margin-bottom: 2rem;
  color: #fff;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.diagram-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 4rem;
}
.diagram-card {
  background: var(--card);
  border: 1px solid var(--border);
  padding: 2rem;
  border-radius: 12px;
  text-align: center;
}
.diagram-card h3 {
  font-size: 1.1rem;
  color: #fff;
  margin: 1.5rem 0 0.5rem 0;
}
.diagram-card p {
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.5;
}

/* MINI VISUAL ENGINES */
.visual-engine {
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}
.node {
  width: 12px;
  height: 12px;
  background: var(--accent);
  border-radius: 50%;
}
.node-locked {
  width: 12px;
  height: 12px;
  border: 2px solid var(--accent);
  border-radius: 3px;
}
.line {
  width: 30px;
  height: 2px;
  background: var(--border);
}
.stack-box {
  width: 30px;
  height: 8px;
  background: var(--border);
  border-radius: 2px;
}
.accent-bg {
  background: var(--accent);
}
.check-shield {
  width: 30px;
  height: 35px;
  border: 2px solid var(--accent);
  border-radius: 4px;
  position: relative;
}
.check-shield::after {
  content: "✓";
  color: var(--accent);
  position: absolute;
  top: 5px;
  left: 8px;
}

/* COLLAPSIBLE DEEP DIVE */
details {
  margin: 2rem 0;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem;
  background: var(--card);
  transition: border-color 0.3s;
}
details[open] {
  border-color: var(--accent);
}
summary::-webkit-details-marker {
  display: none;
} /* Hide default arrow */
details .card {
  border: none;
  padding-top: 1rem;
}

/* PASSING IT ON SECTION */
.hand-off-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 3rem;
  display: flex;
  align-items: center;
  gap: 3rem;
}
.hand-off-text {
  flex: 1;
}
.hand-off-text h3 {
  color: #fff;
  margin-top: 0;
}
.hand-off-visual {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 15px;
}
.flow-step {
  border: 1px solid var(--border);
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 0.85rem;
}
.accent-border {
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}
.flow-arrow {
  color: var(--muted);
}

/* SECURITY PILLARS */
.pillar-item {
  background: var(--card);
  margin-bottom: 0.75rem;
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
}
.pillar-item strong {
  color: #fff;
  display: block;
  margin-bottom: 0.25rem;
}
.pillar-item span {
  color: var(--muted);
  font-size: 0.95rem;
}

/* MISSION SECTION */
.mission-section {
  margin: 4rem 0;
  padding: 2.5rem;
  background: rgba(47, 129, 247, 0.05);
  border-radius: 12px;
  border: 1px solid rgba(47, 129, 247, 0.2);
  text-align: center;
}
.mission-section p {
  font-style: italic;
  font-size: 1.1rem;
  color: var(--text);
  margin: 0;
  line-height: 1.7;
}

/* WAITLIST FORM */
.form-group {
  background: var(--card);
  padding: 4rem 2rem;
  border-radius: 16px;
  border: 1px solid var(--accent);
  text-align: center;
  margin-top: 4rem;
}
input {
  background: var(--bg);
  border: 1px solid var(--border);
  color: white;
  padding: 0.9rem 1rem;
  border-radius: 8px;
  width: 280px;
  font-size: 1rem;
  margin-bottom: 1rem;
  outline: none;
}
input:focus {
  border-color: var(--accent);
}
button {
  background: var(--accent);
  color: white;
  border: none;
  padding: 0.9rem 2.5rem;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  transition: filter 0.2s;
}
button:hover {
  filter: brightness(1.1);
}

/* FOOTER */
footer {
  text-align: center;
  padding: 4rem 0;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}
footer a {
  color: var(--accent);
  text-decoration: none;
  margin: 0 10px;
  font-weight: 500;
}
footer a:hover {
  text-decoration: underline;
}

/* MOBILE RESPONSIVENESS */
@media (max-width: 768px) {
  .diagram-grid,
  .hand-off-box {
    grid-template-columns: 1fr;
    flex-direction: column;
    text-align: center;
  }
  input {
    width: 100%;
    box-sizing: border-box;
  }
  h1 {
    font-size: 2.5rem;
  }
}