@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;700&display=swap');

body {
  font-family: 'Inter', var(--font-family, Arial, sans-serif);
  background: var(--color-bg);
  color: var(--color-text);
  margin: 0;
  min-height: 100vh;
}

.demo-box {
  width: 300px;
  height: 250px;
  transition: all 0.3s ease-in-out;
}

/* Writing mode classes */
.wm-horizontal-tb { writing-mode: horizontal-tb; }
.wm-vertical-rl { writing-mode: vertical-rl; }
.wm-vertical-lr { writing-mode: vertical-lr; }
.wm-sideways-rl { writing-mode: sideways-rl; }
.wm-sideways-lr { writing-mode: sideways-lr; }

/* Utility classes */
.mb-12 { margin-bottom: 3rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mb-8 { margin-bottom: 2rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-1 { margin-bottom: 0.25rem; }
.mt-6 { margin-top: 1.5rem; }
.p-4 { padding: 1rem; }
.p-6 { padding: 1.5rem; }
.p-8 { padding: 2rem; }
.rounded { border-radius: var(--radius-sm); }
.rounded-md { border-radius: 0.75rem; }
.rounded-xl { border-radius: 1.25rem; }
.shadow-lg { box-shadow: var(--shadow-card-hover); }
.shadow { box-shadow: var(--shadow); }
.font-bold { font-weight: 700; }
.font-semibold { font-weight: 600; }
.font-medium { font-weight: 500; }
.text-2xl { font-size: 1.5rem; }
.text-3xl { font-size: 2rem; }
.text-xl { font-size: 1.25rem; }
.text-blue-700 { color: #2563eb; }
.text-gray-600 { color: #4b5563; }
.text-gray-800 { color: #1f2937; }
.bg-white { background: #fff; }
.bg-gray-50 { background: #f9fafb; }
.bg-gray-100 { background: #f3f4f6; }
.bg-sky-100 { background: #e0f2fe; }
.border { border: 1px solid #e5e7eb; }
.border-sky-400 { border-color: #38bdf8; }
.block { display: block; }
.flex { display: flex; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-center { justify-content: center; }
.w-full { width: 100%; }
.max-w-5xl { max-width: 64rem; }
.mx-auto { margin-left: auto; margin-right: auto; }
.overflow-auto { overflow: auto; }
.min-h-\[350px\] { min-height: 350px; }
.space-y-3 > * + * { margin-top: 0.75rem; }
.gap-8 { gap: 2rem; }
.gap-4 { gap: 1rem; }
.w-1\/3 { width: 33.333333%; }
.w-2\/3 { width: 66.666667%; }
.list-disc { list-style: disc; }
.pl-6 { padding-left: 1.5rem; }
.mr-2 { margin-right: 0.5rem; }
.text-center { text-align: center; }
.w-90 { width: 90%; }

/* Root Variables */
:root {
  --color-primary: #2d8cf0;
  --color-secondary: #7c3aed;
  --color-bg: #f8fafc;
  --color-white: #fff;
  --color-gray: #e5e7eb;
  --color-text: #22223b;
  --color-tip: #fef9c3;
  --color-tip-border: #fde047;
  --color-note-bg: #e0f2fe;
  --color-note-text: #217dbb;
  --color-theory-bg: #f3e8ff;
  --color-hover: #ffd200;
  --gradient-back-btn: linear-gradient(90deg, #3498db 60%, #8e44ad 100%);
  --shadow: 0 2px 12px rgba(44,62,80,0.07);
  --shadow-btn: 0 2px 8px 0 rgba(52, 152, 219, 0.12);
  --shadow-btn-hover: 0 4px 12px 0 rgba(52, 152, 219, 0.2);
  --shadow-card: 0 1px 6px rgba(44,62,80,0.06);
  --shadow-card-hover: 0 4px 18px rgba(44,62,80,0.13);
  --shadow-demo: 0 1px 4px rgba(44,62,80,0.04);
  --radius: 0.75rem;
  --radius-sm: 0.4rem;
  --spacing: 1.2rem;
  --spacing-lg: 2rem;
  --font-family: 'Segoe UI', Arial, sans-serif;
  --transition-default: 0.2s;
  --border-width-left: 0.25rem;
  --border-width-left-lg: 0.35rem;
  --color-tip-text: #b8860b;
}

/* Components */
.back-btn {
  display: inline-block;
  margin-top: 1.5rem;
  padding: 0.625rem 1.375rem;
  background: var(--gradient-back-btn);
  color: var(--color-white);
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  box-shadow: var(--shadow-btn);
  transition: color var(--transition-default), box-shadow var(--transition-default), transform var(--transition-default);
}
.back-btn:hover {
  color: var(--color-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-btn-hover);
}

.container {
  max-width: 900px;
  margin: var(--spacing-lg) auto;
  background: var(--color-white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: var(--spacing-lg) var(--spacing) var(--spacing) var(--spacing);
}

.theory-section {
  border-left: var(--border-width-left-lg) solid var(--color-secondary);
  background: var(--color-theory-bg);
  padding: var(--spacing) var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}
.theory-section h1 {
  color: var(--color-secondary);
  margin-top: 0;
}
.theory-section code {
  background: var(--color-gray);
  color: var(--color-primary);
  padding: 0.1em 0.4em;
  border-radius: var(--radius-sm);
  font-size: 1em;
}
.syntax-block {
  background: var(--color-bg);
  border-left: var(--border-width-left) solid var(--color-primary);
  padding: 1em 1.5em;
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing);
}
.tip-block {
  display: flex;
  align-items: center;
  background: var(--color-tip);
  border-left: var(--border-width-left) solid var(--color-tip-border);
  padding: 0.7em 1.2em;
  border-radius: var(--radius-sm);
  margin-bottom: var(--spacing);
  font-size: 1.04em;
  color: var(--color-tip-text);
}
.tip-icon {
  font-size: 1.3em;
  margin-right: 0.5em;
}
.examples-section {
  margin-bottom: var(--spacing-lg);
}
.example-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing);
  margin-bottom: var(--spacing);
}
.example-card {
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-card);
  padding: var(--spacing) var(--spacing) 1.2rem var(--spacing);
  flex: 1 1 15rem;
  min-width: 13rem;
  max-width: 18rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: box-shadow var(--transition-default), transform var(--transition-default);
}
.example-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-0.18rem) scale(1.03);
}
.writing-demo {
  background: var(--color-white);
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--color-gray);
  margin-bottom: 0.7em;
  padding: 0.7em 1em;
  min-height: 4.5em;
  min-width: 7em;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.08em;
  font-weight: 500;
  color: var(--color-text);
  box-shadow: var(--shadow-demo);
}
pre {
  background: var(--color-gray);
  border-radius: var(--radius-sm);
  padding: 0.7em 1em;
  font-size: 0.98em;
  overflow-x: auto;
  margin: 0.5em 0 0 0;
  width: 100%;
}
.note {
  background: var(--color-note-bg);
  color: var(--color-note-text);
  border-left: var(--border-width-left) solid var(--color-primary);
  padding: 0.7em 1.2em;
  border-radius: var(--radius-sm);
  margin-top: 1.2em;
  font-size: 1.02em;
}
.references {
  background: var(--color-theory-bg);
  border-left: var(--border-width-left) solid var(--color-secondary);
  padding: 1.2em 1.5em;
  border-radius: var(--radius-sm);
}
.references ul {
  margin: 0.5em 0 0 1.2em;
}
.references a {
  color: var(--color-primary);
  text-decoration: underline;
  transition: color var(--transition-default);
}
.references a:hover {
  color: var(--color-secondary);
}
@media (max-width: 700px) {
  .container {
    padding: var(--spacing) var(--spacing);
  }
  .example-grid {
    flex-direction: column;
    gap: var(--spacing);
  }
}