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

body {
  font-family: system-ui, sans-serif;
  background-color: #fafafa;
  color: #222;
  line-height: 1.7;
}

header {
  background: white;
  padding: 1.5rem;
  text-align: center;
  border-bottom: 1px solid #ddd;
}

nav a {
  margin: 0 0.75rem;
  text-decoration: none;
  color: #444;
}

main {
  max-width: 800px;
  margin: 3rem auto;
  padding: 0 1rem;
}

footer {
  text-align: center;
  font-size: 0.9rem;
  color: #666;
  padding: 1.5rem;
  border-top: 1px solid #ddd;
}

.intro-section {
  margin-top: 2.5rem;
}

.intro-box {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.icon {
  font-size: 1.5rem;
  line-height: 1;
}

.intro-text {
  display: flex;
  flex-direction: column; /* THIS is the key line */
  gap: 0.5rem;
}

.level-title {
  font-weight: 600;
}

.peel {
  list-style: none;     
  padding-left: 0;      
}

.peel li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

h3 {
  margin-top: 2.5rem;
  margin-bottom: 1rem;
}

.peel {
  background-color: #ffffff;
  padding: 1rem 1.25rem;
  border-left: 4px solid #ccc;
  border-radius: 6px;
}

.button-grid {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.topic-btn {
  display: inline-block;
  width: 100%;
  max-width: 360px;
  padding: 0.85rem 1.4rem;
  background-color: #f3f3f3;
  color: #222;
  border: 2px solid #888;
  border-radius: 6px;
  font-size: 1.05rem;
  font-weight: 500;
  text-decoration: none;
  text-align: center;
  transition: background-color 0.2s ease, transform 0.15s ease;
}

.topic-btn:hover {
  background-color: #e0e0e0;
  transform: translateY(-2px);
}

.about {
  max-width: 700px;
  margin: 3rem auto;
}

.about p {
  margin-bottom: 1.2rem;
}