/* Teaching workspace — shared lesson stylesheet */
:root {
  --fg: #2d2d2d;
  --bg: #fffff8;
  --accent: #e63946;
  --code-bg: #f5f5f0;
  --border: #ddd;
  --link: #457b9d;
  --success: #2a9d8f;
  --warning: #e9c46a;
  --font-body: 'Palatino Linotype', 'Book Antiqua', Palatino, serif;
  --font-code: 'Fira Code', 'Source Code Pro', 'Consolas', monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: var(--font-body);
  color: var(--fg);
  background: var(--bg);
  max-width: 740px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
  line-height: 1.7;
  font-size: 18px;
}

h1 { font-size: 2rem; margin: 2rem 0 1rem; font-weight: 400; letter-spacing: -0.02em; }
h2 { font-size: 1.4rem; margin: 2rem 0 0.8rem; font-weight: 600; color: var(--accent); border-bottom: 1px solid var(--border); padding-bottom: 0.3rem; }
h3 { font-size: 1.1rem; margin: 1.5rem 0 0.5rem; font-weight: 600; }

p { margin: 0.8rem 0; }
a { color: var(--link); text-decoration: none; border-bottom: 1px solid transparent; }
a:hover { border-bottom-color: var(--link); }

code {
  font-family: var(--font-code);
  font-size: 0.85em;
  background: var(--code-bg);
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

pre {
  background: var(--code-bg);
  border-left: 3px solid var(--accent);
  padding: 1rem 1.2rem;
  margin: 1rem 0;
  overflow-x: auto;
  line-height: 1.5;
  font-size: 0.85rem;
}
pre code { background: none; padding: 0; }

.note {
  background: #f0f7ff;
  border-left: 3px solid var(--link);
  padding: 0.8rem 1rem;
  margin: 1rem 0;
  font-size: 0.95rem;
}

.warning {
  background: #fff8e1;
  border-left: 3px solid var(--warning);
  padding: 0.8rem 1rem;
  margin: 1rem 0;
  font-size: 0.95rem;
}

.key-insight {
  background: #f0fff4;
  border-left: 3px solid var(--success);
  padding: 0.8rem 1rem;
  margin: 1rem 0;
  font-size: 0.95rem;
}

figure {
  margin: 1.5rem 0;
  text-align: center;
}
figcaption {
  font-size: 0.85rem;
  color: #666;
  margin-top: 0.5rem;
  font-style: italic;
}

table {
  border-collapse: collapse;
  width: 100%;
  margin: 1rem 0;
  font-size: 0.9rem;
}
th, td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.8rem;
  text-align: left;
}
th { background: var(--code-bg); font-weight: 600; }

.diagram {
  font-family: var(--font-code);
  font-size: 0.8rem;
  line-height: 1.4;
  white-space: pre;
  background: var(--code-bg);
  padding: 1.2rem;
  margin: 1rem 0;
  border-radius: 4px;
  overflow-x: auto;
}

.quiz {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1.2rem;
  margin: 1.5rem 0;
}
.quiz h3 { margin-top: 0; color: var(--accent); }
.quiz label {
  display: block;
  padding: 0.4rem 0.6rem;
  margin: 0.3rem 0;
  border-radius: 4px;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 0.9rem;
}
.quiz label:hover { background: #e8e8e0; }
.quiz input[type="radio"] { margin-right: 0.5rem; }
.quiz .feedback {
  display: none;
  margin-top: 0.8rem;
  padding: 0.6rem;
  border-radius: 4px;
  font-size: 0.9rem;
}
.quiz .feedback.correct { background: #d4edda; display: block; }
.quiz .feedback.wrong { background: #f8d7da; display: block; }

.nav-footer {
  margin-top: 3rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: #666;
}

@media print {
  body { max-width: none; padding: 1cm; font-size: 11pt; }
  .quiz { page-break-inside: avoid; }
  pre { font-size: 9pt; }
}