:root {
  --bg: #f7f7f8;
  --text: #1f2937;
  --card: #ffffff;
  --accent: #2563eb;
}

[data-theme="dark"] {
  --bg: #0f172a;
  --text: #e5e7eb;
  --card: #1e293b;
  --accent: #60a5fa;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.hero {
  padding: 4rem 1.5rem;
  text-align: center;
  background: var(--card);
  border-bottom: 1px solid rgba(127, 127, 127, 0.2);
}

.hero h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(2rem, 5vw, 3.5rem);
}

.hero p {
  margin: 0 0 1.5rem;
  opacity: 0.8;
}

button {
  border: 0;
  padding: 0.75rem 1.25rem;
  border-radius: 999px;
  background: var(--accent);
  color: white;
  font-size: 1rem;
  cursor: pointer;
}

main {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

section {
  background: var(--card);
  padding: 1.5rem;
  border-radius: 1rem;
  margin-bottom: 1rem;
}

footer {
  text-align: center;
  padding: 2rem;
  opacity: 0.7;
}

/* 文字实验室 */
.hint {
  opacity: 0.7;
  font-size: 0.95rem;
  margin-top: 0;
}

#labInput {
  width: 100%;
  padding: 0.75rem;
  border-radius: 0.5rem;
  border: 1px solid rgba(127, 127, 127, 0.3);
  background: var(--bg);
  color: var(--text);
  font-size: 1rem;
  font-family: inherit;
  resize: vertical;
}

#labInput:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.lab-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.75rem;
}

button.secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid rgba(127, 127, 127, 0.4);
}

.lab-result {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: 0.5rem;
  background: var(--bg);
  border: 1px solid rgba(127, 127, 127, 0.2);
}

.lab-result dl {
  margin: 0;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.5rem 1rem;
}

.lab-result dt {
  font-weight: 600;
  opacity: 0.8;
}

.lab-result dd {
  margin: 0;
  word-break: break-word;
}