:root {
  --bg: linear-gradient(to right, #dbeafe, #e0e7ff);
  --card-bg: #ffffff;
  --text-color: #1e293b;
  --primary: #2563eb;
  --accent: #64748b;
  --highlight: #facc15;
  --font: 'Segoe UI', sans-serif;
  --dark-bg: #0f172a;
  --dark-card: #1e293b;
  --dark-text: #e2e8f0;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-color);
  line-height: 1.7;
  transition: all 0.3s ease;
}

body.dark {
  background: var(--dark-bg);
  color: var(--dark-text);
}

body.dark .card,
body.dark .cta-card {
  background: var(--dark-card);
  color: var(--dark-text);
}

body::before,
body::after {
  content: '';
  position: fixed;
  top: 0;
  width: 10px;
  height: 100%;
  background: linear-gradient(to bottom, #93c5fd, #c4b5fd);
  opacity: 0.3;
  z-index: 0;
}

body::before { left: 0; }
body::after  { right: 0; }

header {
  text-align: center;
  padding: 3rem 1rem;
  position: relative;
  z-index: 1;
}

header h1 {
  font-size: 3rem;
  color: var(--primary);
}

.highlight {
  color: var(--highlight);
  font-weight: bold;
}

main {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

.card, .cta-card {
  background: var(--card-bg);
  padding: 2rem;
  margin-bottom: 2rem;
  border-radius: 12px;
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
  position: relative;
  z-index: 1;
}

.cta-card {
  background: #fefce8;
  border-left: 6px solid #facc15;
}

.cta-button {
  display: inline-block;
  margin-top: 1rem;
  background-color: #facc15;
  color: #1e293b;
  font-weight: bold;
  padding: 0.6rem 1rem;
  border-radius: 6px;
  text-decoration: none;
}

.cta-button:hover {
  background-color: #eab308;
}

h2 {
  color: var(--primary);
  margin-bottom: 1rem;
}

ul {
  list-style: none;
  padding-left: 1rem;
}

ul li::before {
  content: '•';
  color: var(--primary);
  font-weight: bold;
  margin-right: 0.5rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
}

th, td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid #ccc;
}

.note {
  font-size: 0.9rem;
  color: var(--accent);
  margin-top: 0.5rem;
}

blockquote {
  background-color: #f8fafc;
  padding: 1rem;
  border-left: 4px solid var(--primary);
  margin: 1rem 0;
  border-radius: 8px;
  font-style: italic;
}

blockquote footer {
  text-align: right;
  font-size: 0.9rem;
  color: var(--accent);
}

form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

form label {
  display: flex;
  flex-direction: column;
  font-weight: 600;
}

input, textarea {
  margin-top: 0.25rem;
  padding: 0.5rem;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 1rem;
}

button {
  align-self: flex-start;
  background: var(--primary);
  color: white;
  padding: 0.6rem 1.2rem;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-weight: bold;
}

button:hover {
  background: #1d4ed8;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

footer {
  text-align: center;
  padding: 2rem;
  font-size: 0.9rem;
  color: var(--accent);
}

body.dark blockquote {
  background-color: #334155;
  color: #e2e8f0;
}

body.dark details summary {
  color: #f8fafc;
}

details summary {
  cursor: pointer;
  font-weight: 600;
  margin-top: 1rem;
  padding: 0.5rem;
  border: 1px solid #ddd;
  border-radius: 6px;
  background-color: #f1f5f9;
}

body.dark details summary {
  background-color: #1e293b;
  border-color: #475569;
}

details p {
  padding: 0.5rem 1rem;
  color: var(--text-color);
}

body.dark details p {
  color: var(--dark-text);
}

#easter-egg {
  margin-top: 1rem;
  color: limegreen;
  font-family: monospace;
  font-weight: bold;
}

.dark-mode-toggle {
  position: fixed;
  top: 10px;
  right: 20px;
  z-index: 999;
  font-size: 0.9rem;
  background: rgba(255, 255, 255, 0.8);
  padding: 5px 10px;
  border-radius: 6px;
}