:root {
  --blue: #0b3d91;
  --light-blue: #e8f0ff;
  --white: #ffffff;
  --text: #14213d;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 70px; /* keeps headings below the fixed bar */
}

body {
  margin: 0;
  font-family: "Montserrat", sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
}

/* top bar */
nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 60px;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--blue);
  z-index: 10;
}

nav .brand {
  color: var(--white);
  font-weight: 800;
  text-decoration: none;
}

nav ul {
  display: flex;
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
}

nav ul a {
  color: var(--white);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  opacity: 0.85;
}

nav ul a:hover { opacity: 1; text-decoration: underline; }

/* hero */
header {
  margin-top: 60px;
  padding: 100px 24px;
  text-align: center;
  color: var(--white);
  background: linear-gradient(135deg, var(--blue), #2f6fed);
}

header h1 { margin: 0; font-size: 3rem; font-weight: 800; }
header p { margin: 12px 0 0; font-size: 1.2rem; }

/* sections */
main section {
  max-width: 900px;
  margin: 0 auto;
  padding: 72px 24px;
}

main section.highlight {
  max-width: none;
  background: var(--light-blue);
}

main section.highlight > * {
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

h2 {
  margin: 0 0 24px;
  color: var(--blue);
  font-weight: 800;
  font-size: 2rem;
}

/* visualization */
.lead { font-size: 1.1rem; font-weight: 600; }

/* one chart per row: the charts are wide and their labels get unreadable in two columns */
.gallery {
  display: grid;
  gap: 40px;
  margin: 24px 0 48px;
}

figure { margin: 0; }
figure img { display: block; width: 100%; height: auto; border-radius: 8px; border: 1px solid var(--light-blue); }
figcaption { margin-top: 8px; font-size: 0.85rem; opacity: 0.7; }

/* prediction cards */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.card {
  padding: 24px;
  text-align: center;
  background: var(--white);
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(11, 61, 145, 0.15);
}

.card .big {
  display: block;
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--blue);
}

/* technical */
pre {
  padding: 16px;
  overflow-x: auto;
  color: var(--white);
  background: var(--blue);
  border-radius: 8px;
}

footer {
  padding: 24px;
  text-align: center;
  color: var(--white);
  background: var(--blue);
  font-size: 0.85rem;
}

@media (max-width: 700px) {
  nav .brand { display: none; }
  nav { justify-content: center; padding: 0 8px; }
  nav ul { gap: 12px; }
  nav ul a { font-size: 0.7rem; }
  header h1 { font-size: 2rem; }
}

/* extra content styles */
h3 { margin: 32px 0 8px; color: var(--blue); font-weight: 600; }

main ul { padding-left: 20px; }
main li { margin-bottom: 8px; }

table {
  width: 100%;
  margin: 16px 0;
  border-collapse: collapse;
  background: var(--white);
}

th, td { padding: 10px 14px; text-align: left; border-bottom: 1px solid var(--light-blue); }
th { color: var(--white); background: var(--blue); }

.note { font-size: 0.85rem; opacity: 0.7; }