:root {
  --bg: #07111f;
  --bg-light: #0b1b30;
  --card: #0d2036;
  --card-hover: #112a45;
  --text: #f5f9ff;
  --muted: #9fb1c7;
  --accent: #39d9ff;
  --accent-2: #7c5cff;
  --border: rgba(255, 255, 255, 0.09);
  --success: #46e6a5;
  --warning: #ffc857;
}

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

html {
  scroll-behavior: smooth;
}

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

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

.container {
  width: min(1180px, 92%);
  margin: 0 auto;
}

/* =========================
   NAVIGATION
========================= */

.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(7, 17, 31, 0.82);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border);
}

.nav-content {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 1px;
}

.brand-icon {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--accent);
  border: 1px solid rgba(57, 217, 255, 0.35);
  background: rgba(57, 217, 255, 0.08);
  font-size: 21px;
}

nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

nav a {
  color: var(--muted);
  font-size: 14px;
  font-weight: 600;
  transition: 0.2s ease;
}

nav a:hover {
  color: var(--text);
}

.nav-button {
  padding: 10px 18px;
  border-radius: 10px;
  color: #04101c !important;
  background: var(--accent);
}

/* =========================
   HERO
========================= */

.hero {
  position: relative;
  min-height: 680px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background:
    radial-gradient(circle at 75% 45%, rgba(57, 217, 255, 0.12), transparent 28%),
    radial-gradient(circle at 20% 30%, rgba(124, 92, 255, 0.11), transparent 30%);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  opacity: 0.2;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 55px 55px;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
  gap: 50px;
}

.badge,
.section-label {
  color: var(--accent);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 2px;
}

.badge {
  display: inline-block;
  padding: 8px 13px;
  border: 1px solid rgba(57, 217, 255, 0.2);
  border-radius: 30px;
  background: rgba(57, 217, 255, 0.06);
  margin-bottom: 22px;
}

.hero h1 {
  max-width: 720px;
  font-size: clamp(48px, 7vw, 82px);
  line-height: 0.98;
  letter-spacing: -3px;
  margin-bottom: 25px;
}

.hero h1 span,
.about-section h2 span {
  color: var(--accent);
}

.hero-text > p {
  max-width: 590px;
  color: var(--muted);
  font-size: 18px;
  margin-bottom: 32px;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 13px;
}

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 21px;
  border-radius: 11px;
  font-size: 14px;
  font-weight: 750;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.primary-button {
  color: #03111c;
  background: var(--accent);
  box-shadow: 0 0 25px rgba(57, 217, 255, 0.16);
}

.secondary-button {
  border: 1px solid var(--border);
  background: rgba(255,255,255,0.035);
}

.primary-button:hover,
.secondary-button:hover {
  transform: translateY(-2px);
}

.primary-button:hover {
  box-shadow: 0 8px 30px rgba(57, 217, 255, 0.22);
}

/* =========================
   SCIENCE VISUAL
========================= */

.science-orbit {
  position: relative;
  width: 430px;
  height: 430px;
  margin: auto;
}

.orbit {
  position: absolute;
  inset: 50%;
  border: 1px solid rgba(57, 217, 255, 0.22);
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.orbit-one {
  width: 310px;
  height: 150px;
  transform: translate(-50%, -50%) rotate(30deg);
}

.orbit-two {
  width: 310px;
  height: 150px;
  transform: translate(-50%, -50%) rotate(-30deg);
}

.atom {
  position: absolute;
  width: 105px;
  height: 105px;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  background: radial-gradient(circle, rgba(57,217,255,0.45), rgba(57,217,255,0.04) 65%);
  box-shadow: 0 0 70px rgba(57, 217, 255, 0.25);
}

.atom::after {
  content: "⚛";
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: var(--accent);
  font-size: 52px;
}

.floating-symbol {
  position: absolute;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: rgba(13, 32, 54, 0.8);
  color: var(--accent);
  font-size: 21px;
  box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

.symbol-one {
  top: 40px;
  right: 55px;
}

.symbol-two {
  bottom: 65px;
  left: 30px;
}

.symbol-three {
  bottom: 20px;
  right: 80px;
}

/* =========================
   STATS
========================= */

.stats {
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,0.018);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.stat {
  padding: 30px;
  text-align: center;
  border-right: 1px solid var(--border);
}

.stat:last-child {
  border-right: none;
}

.stat strong {
  display: block;
  color: var(--accent);
  font-size: 31px;
  margin-bottom: 2px;
}

.stat span {
  color: var(--muted);
  font-size: 13px;
}

/* =========================
   SECTIONS
========================= */

.section {
  padding: 110px 0;
}

.section-heading {
  max-width: 680px;
  margin-bottom: 48px;
}

.section-heading h2,
.about-section h2,
.contact-box h2 {
  font-size: clamp(35px, 5vw, 53px);
  line-height: 1.05;
  letter-spacing: -1.5px;
  margin: 9px 0 17px;
}

.section-heading p,
.about-section p,
.contact-box p {
  color: var(--muted);
}

/* =========================
   COMPETITIONS
========================= */

.competition-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 17px;
}

.competition-card {
  position: relative;
  min-height: 190px;
  padding: 25px;
  border: 1px solid var(--border);
  border-radius: 18px;
  background: linear-gradient(
    145deg,
    rgba(13, 32, 54, 0.95),
    rgba(9, 24, 41, 0.95)
  );
  transition: 0.25s ease;
  overflow: hidden;
}

.competition-card::before {
  content: "";
  position: absolute;
  width: 120px;
  height: 120px;
  right: -50px;
  top: -50px;
  border-radius: 50%;
  background: rgba(57,217,255,0.06);
}

.competition-card:hover {
  transform: translateY(-5px);
  border-color: rgba(57, 217, 255, 0.25);
  background: var(--card-hover);
}

.competition-number {
  color: rgba(255,255,255,0.35);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 1px;
}

.competition-card h3 {
  font-size: 19px;
  margin: 16px 0 8px;
}

.competition-card p {
  color: var(--muted);
  font-size: 13px;
}

.competition-meta {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.meta {
  padding: 5px 9px;
  border-radius: 7px;
  font-size: 11px;
  font-weight: 700;
  background: rgba(255,255,255,0.06);
  color: var(--muted);
}

.meta.paid {
  color: var(--warning);
  background: rgba(255,200,87,0.08);
}

.meta.free {
  color: var(--success);
  background: rgba(70,230,165,0.08);
}

.register-card-button {
  display: inline-block;
  margin-top: 18px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 750;
}

.loading-card {
  grid-column: 1 / -1;
  padding: 60px;
  text-align: center;
  color: var(--muted);
  border: 1px dashed var(--border);
  border-radius: 18px;
}

.loading-spinner {
  width: 30px;
  height: 30px;
  margin: 0 auto 12px;
  border: 3px solid rgba(255,255,255,0.1);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* =========================
   ABOUT
========================= */

.about-section {
  background:
    radial-gradient(circle at 80% 50%, rgba(124,92,255,0.08), transparent 28%),
    rgba(255,255,255,0.015);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.about-section p {
  margin-bottom: 18px;
}

/* =========================
   CONTACT
========================= */

.contact-section {
  padding: 90px 0;
}

.contact-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 35px;
  padding: 48px;
  border: 1px solid var(--border);
  border-radius: 25px;
  background:
    radial-gradient(circle at 85% 50%, rgba(57,217,255,0.08), transparent 30%),
    var(--card);
}

/* =========================
   FOOTER
========================= */

footer {
  border-top: 1px solid var(--border);
  padding: 35px 0;
}

.footer-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer-content strong {
  font-size: 15px;
}

.footer-content p {
  color: var(--muted);
  font-size: 12px;
}

/* =========================
   MOBILE
========================= */

@media (max-width: 900px) {

  nav a:not(.nav-button) {
    display: none;
  }

  .hero {
    min-height: auto;
    padding: 90px 0;
  }

  .hero-content {
    grid-template-columns: 1fr;
  }

  .science-orbit {
    width: 330px;
    height: 330px;
  }

  .competition-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

@media (max-width: 600px) {

  .nav-content {
    min-height: 68px;
  }

  .brand {
    font-size: 14px;
  }

  .hero h1 {
    font-size: 48px;
    letter-spacing: -2px;
  }

  .hero-text > p {
    font-size: 16px;
  }

  .science-orbit {
    width: 280px;
    height: 280px;
  }

  .stats-grid {
    grid-template-columns: 1fr;
  }

  .stat {
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .stat:last-child {
    border-bottom: none;
  }

  .competition-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 75px 0;
  }

  .contact-box {
    flex-direction: column;
    align-items: flex-start;
    padding: 30px;
  }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
  }
}