* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Segoe UI', sans-serif;
  background-color: #f9f9f9;
  color: #333;
  max-width: 850px;
  margin: 40px auto;
  padding: 20px;
  transition: background-color 0.3s, color 0.3s;
}

body.dark-mode {
  background-color: #1e1e1e;
  color: #eee;
}

h1, h2, h3 {
  color: #2e2e2e;
  margin-top: 0;
}

body.dark-mode h1,
body.dark-mode h2,
body.dark-mode h3 {
  color: #f0f0f0;
}

/* =========================
   Navigation
========================= */
nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 20px;
  justify-content: center;
}

nav a {
  background-color: #0077cc;
  color: white;
  padding: 10px 16px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  transition: background 0.25s;
}

nav a:hover {
  background-color: #005fa3;
}

body.dark-mode nav a {
  background-color: #005fa3;
}

body.dark-mode nav a:hover {
  background-color: #0077cc;
}

/* =========================
   Sections & Lists
========================= */
section {
  margin-bottom: 40px;
  scroll-margin-top: 100px;
}

ul {
  padding-left: 20px;
}

li {
  margin-bottom: 10px;
}

/* =========================
   Highlight Boxes
========================= */
.highlight {
  background-color: #fff3cd;
  padding: 14px;
  border-left: 5px solid #ffc107;
  margin: 20px 0;
  border-radius: 6px;
}

body.dark-mode .highlight {
  background-color: #2a2a2a;
  border-left-color: #ffc107;
  color: #e6e6e0;
}

/* =========================
   Toggle
========================= */
.toggle-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.toggle-button {
  padding: 8px 16px;
  border-radius: 6px;
  background-color: #555;
  color: white;
  border: none;
  cursor: pointer;
  font-weight: bold;
  transition: background-color 0.3s;
}

.toggle-button:hover {
  background-color: #333;
}

/* =========================
   Info Grid / Cards
========================= */
.info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin: 15px 0;
}

.card {
  background-color: #f1f1f1;
  padding: 14px;
  border-radius: 8px;
  line-height: 1.45;
}

body.dark-mode .card {
  background-color: #263239;
  color: #e6eef6;
}

/* =========================
   Tagline
========================= */
.tagline {
  background-color: #e7f3ff;
  padding: 15px;
  border-left: 5px solid #2196f3;
  margin-top: 50px;
  font-size: 1.05em;
  border-radius: 6px;
}

body.dark-mode .tagline {
  background-color: #1f2e3a;
  border-left-color: #42a5f5;
  color: #dfefff;
}

b {
  font-weight: bold;
  color: #d32f2f;
}

/* =========================
   Footer
========================= */
footer {
  text-align: center;
  font-size: 0.9em;
  color: #777;
  margin-top: 60px;
}

body.dark-mode footer {
  color: #aaa;
}

/* =========================
   Responsive
========================= */
@media (max-width: 700px) {
  body {
    margin: 20px;
    padding: 12px;
  }

  nav {
    flex-direction: column;
    align-items: center;
  }

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