/* ===============================
   Base Styles
   =============================== */
html {
  font-size: 16px; /* Makes rem units predictable */
}

body {
  background-color: #8fc9eb;
  margin: 0;
  font-family: sans-serif;
  line-height: 1.5;
}

/* ===============================
   Header
   =============================== */
header {
  background-color: #0288d1;
  color: black;
  text-align: center;
  padding: 1.5rem 1rem;
  border-radius: 20px;
}

header h1 {
  margin: 0;
  font-size: 2.5rem;
}

/* ===============================
   Main Content
   =============================== */
main {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1rem;
  text-align: center;
}

.intro {
  font-size: 1.5rem;
  line-height: 1.6;
  margin: 1rem 0;
}

/* ===============================
   Table of Contents Button
   =============================== */
.toc-button {
  display: inline-block;
  background-color: #0288d1;
  color: black;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 18px;
  font-size: 2rem;
  cursor: pointer;
  text-decoration: none;
  margin-top: 0.5rem;
  transition: background-color 0.3s ease;
}

.toc-button:hover {
  background-color: #e92c6b;
}

/* ===============================
   Responsive Adjustments
   =============================== */
@media (max-width: 480px) {
  header h1 {
    font-size: 1.8rem;
  }

  .intro,
  p {
    font-size: 1.1rem;
  }

  .toc-button {
    font-size: 1.5rem;
    padding: 0.5rem 1rem;
  }
}