.modern-accordion {
  max-width: 800px;
  margin: 0 auto;
  --primary-color: #2563eb;
  --text-color: #1f2937;
  --border-color: #e5e7eb;
}

.accordion-item {
  border: 1px solid var(--border-color);
  border-radius: 12px;
  margin-bottom: 16px;
  overflow: hidden;
  background: white;
}

.accordion-header {
  width: 100%;
  padding: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s;
}

.accordion-header:hover {
  background-color: #f8fafc;
}

.header-content {
  text-align: left;
}

.label {
  font-size: 14px;
  color: var(--primary-color);
  margin-bottom: 4px;
  display: block;
}

.title {
  font-size: 18px;
  color: var(--text-color);
  margin: 0;
  font-weight: 500;
}

.icon-wrap {
  position: relative;
  width: 24px;
  height: 24px;
}

.line {
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--text-color);
  transition: transform 0.3s ease;
}

.line:first-child {
  transform: translateY(-50%);
}

.line:last-child {
  transform: translateY(-50%) rotate(90deg);
}

.accordion-header.active .line:last-child {
  transform: translateY(-50%) rotate(0);
}

.accordion-body {
  height: 0;
  overflow: hidden;
  transition: height 0.3s ease-out;
}

.body-content {
  padding: 0 24px 24px;
}

/* アニメーション用の状態 */
.accordion-body.entering {
  height: var(--content-height);
}

.accordion-body.leaving {
  height: 0;
}