:root {
  --bg-main: #050814;
  --bg-elevated: #080d1a;
  --bg-alt: #0b1120;
  --border-subtle: #1f2937;
  --text-main: #e5edf7;
  --text-muted: #9ca3af;
  --accent-primary: #3da5ff;
  --accent-cyan: #0fffe3;
  --accent-gold: #f2c94c;
  --accent-violet: #c47dff;
  --accent-red: #ff4f6e;
  --radius-lg: 16px;
  --radius-md: 12px;
  --shadow-deep: 0 30px 80px rgba(0, 0, 0, 0.7);
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Inter", "SF Pro Text", sans-serif;
}

/* RESET */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: radial-gradient(circle at 0 0, #111827 0%, #020617 48%, #020617 100%);
  color: var(--text-main);
  font-family: var(--font-main);
  -webkit-font-smoothing: antialiased;
}

/* BACKGROUND GRID */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
  z-index: -1;
}

/* PAGE WRAPPER */
.page {
  max-width: 1160px;
  margin: 0 auto;
  padding: 24px 16px 40px;
  position: relative;
  z-index: 10;
}

/* ============================
      STICKY PREMIUM NAV
============================ */
.nav {
  position: sticky;
  top: 0;
  width: 100%;

  display: flex;
  align-items: center;
  justify-content: space-between;

  padding: 14px 0 18px;

  background: rgba(5, 8, 20, 0.75);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);

  border-bottom: 1px solid rgba(255,255,255,0.06);

  z-index: 999;
}

/* BRAND */
.nav-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-container {
  width: 32px;
  height: 32px;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 25%, rgba(61,165,255,0.35), transparent 55%),
              rgba(15,23,42,0.9);
  border: 1px solid rgba(148,163,184,0.6);
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-image {
  width: 24px;
  height: 24px;
  object-fit: contain;
}

.brand-name {
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(226,232,240,0.96);
}

/* NAV LINKS */
.nav-right {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-right > a {
  color: rgba(209,213,219,0.78);
  text-decoration: none;
  font-size: 13px;

  padding: 6px 2px;
  transition: color 0.2s ease, text-shadow 0.2s ease;
}

.nav-right > a:hover {
  color: var(--accent-primary);
  text-shadow: 0 0 8px rgba(61,165,255,0.35);
}

/* Active page highlight */
.nav-right a.active {
  color: var(--accent-primary) !important;
  font-weight: 600;
  text-shadow: 0 0 8px rgba(61,165,255,0.35);
}

/* ============================
             HERO
============================ */
.hero {
  position: relative;
  margin-top: 26px;
  margin-bottom: 42px;
  border-radius: 22px;
  padding: 36px 26px 44px;

  background: radial-gradient(circle at 0 0, rgba(61,165,255,0.14), transparent 60%),
              radial-gradient(circle at 100% 100%, rgba(196,125,255,0.16), transparent 65%),
              rgba(8,13,26,0.98);

  box-shadow: var(--shadow-deep);
  overflow: hidden;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(31,41,55,0.3) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(31,41,55,0.36) 1px, transparent 1px);
  background-size: 52px 52px;
  opacity: 0.18;
}

.hero-orbit {
  position: absolute;
  border-radius: 999px;
  border: 1px solid rgba(148,163,184,0.45);
  opacity: 0.4;
}

.hero-orbit-1 {
  width: 380px;
  height: 380px;
  right: -180px;
  top: -120px;
}

.hero-orbit-2 {
  width: 420px;
  height: 420px;
  right: -200px;
  top: -60px;
}

.hero-inner {
  max-width: 640px;
  position: relative;
}

/* HERO LOGO WATERMARK */
.hero .hero-inner::after {
  content: "";
  position: absolute;
  right: -60px;
  bottom: -60px;
  width: 260px;
  height: 260px;

  background: url('../assets/atom-logo.jpg') no-repeat center center;
  background-size: contain;
  opacity: 0.06;
}

/* ============================
           HERO TEXT
============================ */
.hero-tag {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: rgba(148,163,184,0.95);
}

.hero-title {
  margin: 12px 0 16px;
  font-size: clamp(30px, 4vw, 38px);
  font-weight: 600;
}

.hero-subtitle {
  margin: 0 0 22px;
  font-size: 14px;
  color: rgba(209,213,219,0.9);
  max-width: 520px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* BUTTONS */
.btn-primary,
.btn-ghost {
  font-size: 13px;
  border-radius: 999px;
  padding: 9px 18px;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), #60a5fa);
  color: #020617;
  font-weight: 600;
}

.btn-primary:hover {
  filter: brightness(1.08);
}

.btn-ghost {
  border: 1px solid rgba(148,163,184,0.6);
  background: rgba(15,23,42,0.85);
  color: rgba(226,232,240,0.95);
}

.btn-ghost:hover {
  border-color: var(--accent-primary);
}

/* ============================
           SECTIONS
============================ */
.section {
  padding: 30px 0;
}

.section-alt {
  margin: 26px 0;
  padding: 28px 20px;
  border-radius: 20px;
  background: radial-gradient(circle at 0 0, rgba(8,47,73,0.4), transparent 60%),
              rgba(8,13,26,0.95);
  border: 1px solid rgba(31,41,55,0.95);
}

.section-header {
  margin-bottom: 16px;
}

.section-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: rgba(148,163,184,0.9);
}

.section h2 {
  margin: 0;
  font-size: 20px;
  line-height: 1.3;
}

.section-summary {
  margin-top: 16px;
  font-size: 14px;
  color: rgba(209,213,219,0.9);
}

/* GRID */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 18px;
}

.flex-split {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
}

/* ============================
           CARDS
============================ */
.card {
  background: rgba(8,13,26,0.96);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  padding: 16px;
  font-size: 13px;
}

.card h3 {
  margin: 0 0 6px;
}

.card-subtitle {
  font-size: 12px;
  color: #9ca3af;
  margin-bottom: 8px;
}

.card-accent-cyan { border-color: rgba(15,255,227,0.55); }
.card-accent-gold { border-color: rgba(242,201,76,0.55); }
.card-accent-violet { border-color: rgba(196,125,255,0.55); }
.card-accent-red { border-color: rgba(255,79,110,0.55); }

/* ============================
         DIAGRAM BOX
============================ */
.diagram-card {
  flex: 1 1 260px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(148,163,184,0.5);
  background: radial-gradient(circle at 0 0, rgba(56,189,248,0.22), transparent 60%),
              rgba(8,13,26,0.96);
  padding: 16px;
  font-size: 12px;
}

.diagram-title {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 10px;
}

.diagram-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.diagram-list li {
  margin-bottom: 4px;
}

.diagram-indent {
  padding-left: 16px;
  border-left: 1px solid rgba(148,163,184,0.5);
}

/* BULLETS */
.bullets {
  list-style: none;
  padding-left: 0;
  margin-top: 12px;
}

.bullets li {
  margin-bottom: 8px;
  padding-left: 16px;
  position: relative;
}

.bullets li::before {
  content: "•";
  color: var(--accent-primary);
  position: absolute;
  left: 0;
}

/* ============================
           CONTACT CARD
============================ */
.contact-card {
  background: rgba(8,13,26,0.96);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 20px;
}

.contact-email a {
  color: var(--accent-primary);
  text-decoration: none;
}

.contact-email a:hover {
  text-decoration: underline;
}

.contact-note {
  font-size: 12px;
  color: rgba(156,163,175,0.95);
}

/* ============================
             FOOTER
============================ */
.footer {
  border-top: 1px solid rgba(31,41,55,0.95);
  margin-top: 36px;
  padding-top: 16px;

  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;

  gap: 14px;
  font-size: 11px;
  color: rgba(148,163,184,0.96);
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-logo {
  width: 18px;
  height: 18px;
}

.footer-links {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.footer-links a {
  text-decoration: none;
  color: rgba(148,163,184,0.96);
}

.footer-links a:hover {
  color: var(--accent-primary);
}

/* ============================
           ANIMATIONS
============================ */
.section, .hero-inner {
  opacity: 0;
  transform: translateY(16px);
  animation: fadeInUp 0.7s ease-out forwards;
}

@keyframes fadeInUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================
          RESPONSIVE
============================ */
@media (max-width: 900px) {
  .nav-right {
    display: none;
  }
}

@media (max-width: 600px) {
  .hero-title {
    font-size: 26px;
  }
}