* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Comic Sans MS", "Segoe UI", Arial, sans-serif;
  background: linear-gradient(180deg, #e0f7ff 0%, #ffffff 55%, #dff3ff 100%);
  color: #14384f;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 24px;
  background: #0f7fa8;
  color: white;
  box-shadow: 0 4px 12px rgba(15, 127, 168, .25);
}

.logo {
  font-size: 22px;
  font-weight: bold;
}

nav a {
  color: white;
  text-decoration: none;
  margin-left: 14px;
  padding: 8px 14px;
  border-radius: 20px;
  transition: background .2s;
}

nav a:hover,
nav a.active {
  background: #0a5f80;
}

main {
  max-width: 1000px;
  margin: 0 auto;
  padding: 28px 20px 60px;
}

.hero {
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  align-items: center;
  gap: 24px;
  background: white;
  border-radius: 28px;
  padding: 30px;
  box-shadow: 0 10px 25px rgba(20, 56, 79, .12);
}

.hero h1 {
  font-size: 38px;
  margin: 0 0 14px;
  color: #0a5f80;
}

.hero img,
.wide {
  width: 100%;
  border-radius: 22px;
  object-fit: cover;
}

.button {
  display: inline-block;
  margin-top: 16px;
  padding: 12px 22px;
  background: #ffb703;
  color: #14384f;
  font-weight: bold;
  text-decoration: none;
  border-radius: 24px;
  box-shadow: 0 4px 0 #d99700;
}

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

.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 30px;
}

.card,
.fact,
.note {
  background: white;
  border-radius: 22px;
  padding: 20px;
  box-shadow: 0 8px 18px rgba(20, 56, 79, .10);
}

.card h2 {
  margin-top: 0;
  color: #0a5f80;
}

.page {
  background: white;
  border-radius: 28px;
  padding: 30px;
  box-shadow: 0 10px 25px rgba(20, 56, 79, .12);
}

.page h1 {
  color: #0a5f80;
}

.page h2 {
  color: #0f7fa8;
}

.page img {
  margin: 18px 0;
}

.fact {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  margin-bottom: 14px;
}

.emoji {
  font-size: 30px;
}

.note {
  background: #fff4d6;
  border-left: 6px solid #ffb703;
}

.quiz {
  background: #eaf7ff;
  padding: 20px;
  border-radius: 22px;
}

.quiz button {
  margin-top: 10px;
  padding: 10px 18px;
  border: none;
  border-radius: 20px;
  background: #0f7fa8;
  color: white;
  font-weight: bold;
  cursor: pointer;
}

footer {
  text-align: center;
  padding: 22px;
  background: #0f7fa8;
  color: white;
}

@media (max-width: 760px) {
  .hero,
  .cards {
    grid-template-columns: 1fr;
  }

  .site-header {
    flex-direction: column;
  }

  nav a {
    margin: 4px;
  }
}