@charset "UTF-8";

/* ==========================================
   CSS (デザイン・スタイル)
   ========================================== */
:root {
  --primary-color: #ff7e67; /* やさしいコーラルオレンジ */
  --secondary-color: #6bb2a0; /* 安心感のあるミントグリーン */
  --bg-color: #faf6f0; /* 温かみのあるオフホワイト */
  --text-color: #333333;
  --card-bg: #ffffff;
  --radius: 16px;
}

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

body {
  font-family: 'Helvetica Neue', Arial, 'ヒラギノ角ゴ Pro W3', 'Hiragino Kaku Gothic Pro', 'メイリオ', Meiryo, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.8;
}

/* ヘッダー */
header {
  background-color: var(--card-bg);
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  font-size: 1.4rem;
  font-weight: bold;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-header {
  background-color: var(--primary-color);
  color: white;
  padding: 0.5rem 1.2rem;
  border-radius: 30px;
  text-decoration: none;
  font-weight: bold;
  transition: opacity 0.3s;
}

.btn-header:hover {
  opacity: 0.8;
}

/* ヒーローセクション */
.hero {
  text-align: center;
  padding: 4rem 1.5rem;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  background-color: #ffe8e3;
  color: var(--primary-color);
  padding: 0.3rem 1rem;
  border-radius: 20px;
  font-size: 0.9rem;
  font-weight: bold;
  margin-bottom: 1rem;
}

.hero h1 {
  font-size: 2.2rem;
  margin-bottom: 1.5rem;
  color: #2c3e50;
  line-height: 1.4;
}

.hero p {
  font-size: 1.1rem;
  color: #666;
  margin-bottom: 2rem;
}

/* コアコンセプト (削ぎ落とした2つの概念) */
.concept-section {
  background: white;
  padding: 3rem 1.5rem;
  border-radius: var(--radius);
  max-width: 900px;
  margin: 0 auto 3rem auto;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
  text-align: center;
}

.concept-title {
  font-size: 1.5rem;
  margin-bottom: 2rem;
  position: relative;
  display: inline-block;
}

.concept-title::after {
  content: '';
  display: block;
  width: 50px;
  height: 3px;
  background: var(--secondary-color);
  margin: 0.5rem auto 0 auto;
  border-radius: 2px;
}

.concept-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-top: 1.5rem;
}

.concept-card {
  padding: 2rem;
  border-radius: var(--radius);
  background-color: var(--bg-color);
  border: 2px solid transparent;
  transition: transform 0.3s, border-color 0.3s;
}

.concept-card:hover {
  transform: translateY(-5px);
}

.concept-card.purpose {
  border-color: #ffc2b8;
}

.concept-card.role {
  border-color: #b8e2d8;
}

.concept-tag {
  font-size: 0.85rem;
  font-weight: bold;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 0.5rem;
}

.purpose .concept-tag { color: var(--primary-color); }
.role .concept-tag { color: var(--secondary-color); }

.concept-card h3 {
  font-size: 1.8rem;
  margin-bottom: 1rem;
}

/* インタラクティブエリア */
.interactive-section {
  max-width: 800px;
  margin: 0 auto 4rem auto;
  padding: 2rem 1.5rem;
  text-align: center;
}

.tab-buttons {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

.tab-btn {
  background: white;
  border: 2px solid #e0e0e0;
  padding: 0.8rem 1.5rem;
  border-radius: 30px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: bold;
  transition: all 0.3s;
}

.tab-btn.active {
  background-color: var(--secondary-color);
  color: white;
  border-color: var(--secondary-color);
}

.support-box {
  margin-top: 2rem;
  background: white;
  padding: 2rem;
  border-radius: var(--radius);
  box-shadow: 0 4px 15px rgba(0,0,0,0.05);
  text-align: left;
  min-height: 120px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.support-content {
  transition: opacity 0.2s ease-in-out;
}

/* フッター */
footer {
  text-align: center;
  padding: 2rem;
  background-color: #2c3e50;
  color: white;
  font-size: 0.9rem;
}

/* レスポンシブ調整 */
@media (max-width: 600px) {
  .hero h1 { font-size: 1.6rem; }
  .concept-grid { grid-template-columns: 1fr; }
}