:root {
  --color-bg: #f7f7f9;
  --color-text: #1f1f1f;
  --color-muted: #6b6b6b;
  --color-accent: #3b5bfd;
  --color-card-bg: #ffffff;
  --color-border: #e3e3e8;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
}

.app {
  max-width: 640px;
  margin: 2rem auto 4rem;
  padding: 0 1.5rem;
}

.app h1 {
  margin: 0 0 0.5rem;
  font-size: 1.5rem;
  text-align: center;
}

.description {
  margin: 0 0 2rem;
  color: var(--color-muted);
  font-size: 0.9rem;
  text-align: center;
}

.select-block {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 1.25rem;
  margin-bottom: 1.5rem;
}

.select-block h2 {
  margin: 0 0 0.75rem;
  font-size: 1.05rem;
}

.order-toggle {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 0.75rem;
  font-size: 0.9rem;
  color: var(--color-muted);
}

.order-toggle label {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
}

.preview-select {
  display: block;
  width: 100%;
  max-width: 260px;
  padding: 0.5rem 0.6rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.code-block {
  margin: 0 0 0.75rem;
  padding: 0.75rem;
  border-radius: 8px;
  background: #f0f0f4;
  border: 1px solid var(--color-border);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.8rem;
  line-height: 1.5;
  white-space: pre;
  overflow-x: auto;
  max-height: 220px;
  overflow-y: auto;
}

.btn {
  padding: 0.55rem 1.25rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  background: #fff;
  color: var(--color-text);
  font-size: 0.9rem;
  cursor: pointer;
}

.btn:hover {
  background: #f0f0f4;
}