フラットなカード風デザイン

<div class="accordion-card">
  <div class="accordion-item">
    <button class="accordion-question">Q. このアコーディオンはどんな特徴？</button>
    <div class="accordion-answer">
      <p>A. フラットなカード風デザインに、スライドアニメーションを加えたスタイリッシュな仕様です。</p>
    </div>
  </div>

  <div class="accordion-item">
    <button class="accordion-question">Q. どんな人におすすめ？</button>
    <div class="accordion-answer">
      <p>A. 無駄をそぎ落としたUIを求める人、シンプル・機能的なサイトを作りたい方に最適です。</p>
    </div>
  </div>
</div>

.accordion-card {
  max-width: 700px;
  margin: 60px auto;
  font-family: 'Segoe UI', sans-serif;
}

.accordion-item {
  background: #ffffff;
  border: 1px solid #e0e0e0;
  border-radius: 8px;
  margin-bottom: 16px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.05);
  overflow: hidden;
  transition: box-shadow 0.3s ease;
}

.accordion-item:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.accordion-question {
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  padding: 18px 24px;
  font-size: 17px;
  font-weight: bold;
  color: #333;
  cursor: pointer;
  position: relative;
  transition: background-color 0.2s ease;
}

.accordion-question::after {
  content: '+';
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  color: #888;
  transition: transform 0.3s ease;
}

.accordion-question.active::after {
  content: '−';
}

.accordion-answer {
  max-height: 0;
  overflow: hidden;
  padding: 0 24px;
  background: #fafafa;
  font-size: 15px;
  color: #555;
  transition: max-height 0.4s ease, padding 0.4s ease;
}

.accordion-answer.open {
  padding: 16px 24px;
  max-height: 500px; /* Enough height for transition */
}

document.addEventListener('DOMContentLoaded', function () {
  const items = document.querySelectorAll('.accordion-card .accordion-item');

  items.forEach((item) => {
    const question = item.querySelector('.accordion-question');
    const answer = item.querySelector('.accordion-answer');

    question.addEventListener('click', () => {
      question.classList.toggle('active');
      answer.classList.toggle('open');
    });
  });
});