body {
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f8fafc;
  color: #222;
  margin: 0;
  padding: 0;
}

main {
  max-width: 800px;
  margin: 2rem auto;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 24px rgba(0,0,0,0.07);
  padding: 2rem 2.5rem;
}

h1 {
  text-align: center;
  color: #3a3a7a;
  margin-bottom: 2rem;
}

section {
  margin-bottom: 2.5rem;
}

.theory {
  background: #e6f0fa;
  border-left: 5px solid #3498db;
  padding: 1rem 1.5rem;
  border-radius: 6px;
  margin-bottom: 0.5rem;
}

.code-example {
  background: #23272e;
  color: #f8f8f2;
  border-radius: 6px;
  padding: 1rem 1.5rem;
  margin-bottom: 1.5rem;
  box-shadow: 0 2px 8px rgba(52,152,219,0.07);
}

.code-example pre {
  background: #181a20;
  color: #e6db74;
  padding: 0.75rem 1rem;
  border-radius: 4px;
  overflow-x: auto;
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.demo-text {
  background: #f4f8fb;
  color: #23272e;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  margin-top: 0.5rem;
  font-size: 1.1em;
  transition: background 0.2s;
}

.demo-text:hover {
  background: #d6eaff;
}

nav {
  background: #e6f0fa;
  padding: 1rem 0;
  text-align: left;
  border-bottom: 1px solid #d0e2f2;
}

.back-btn {
  background: #3498db;
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 0.5rem 1.2rem;
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.2s, box-shadow 0.2s;
  box-shadow: 0 2px 8px rgba(52,152,219,0.07);
}

.back-btn:hover, .back-btn:focus {
  background: #217dbb;
  outline: none;
}

@media (max-width: 600px) {
  main {
    padding: 1rem 0.5rem;
  }
  h1 {
    font-size: 1.5rem;
  }
}

/* Text property demo classes */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-justify { text-align: justify; }

.underline { text-decoration: underline; }
.overline { text-decoration: overline; }
.line-through { text-decoration: line-through; }
.underline-overline { text-decoration: underline overline; }

.uppercase { text-transform: uppercase; }
.lowercase { text-transform: lowercase; }
.capitalize { text-transform: capitalize; }

.letter-spacing-wide { letter-spacing: 0.2em; }
.letter-spacing-tight { letter-spacing: -0.05em; }

.word-spacing-wide { word-spacing: 1.5em; }
.word-spacing-tight { word-spacing: -0.3em; }

.line-height-loose { line-height: 2; }
.line-height-tight { line-height: 1; }

.text-shadow-basic { text-shadow: 2px 2px 4px #888; }
.text-shadow-color { text-shadow: 1px 1px 6px #3498db; }