:root {
  --primary-color: #c43b2f;      /* 朱色（鬼・出陣） */
  --secondary-color: #1f2c5c;    /* 藍（桃太郎モチーフ） */
  --accent-color: #f3c04b;       /* きびだんご寄りの金 */
  --peach-color: #f7b7a6;        /* 桃 */
  --text-primary: #241b18;
  --text-secondary: #5a4742;
  --bg-primary: #fff3e6;         /* 生成り〜桃色のクリーム */
  --bg-secondary: #ffe4d4;       /* 淡い桃 */
  --border-light: rgba(196,59,47,0.22);
  --shadow-medium: 0 12px 34px rgba(0,0,0,0.14);
}

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

body.oni-theme {
  font-family: 'Zen Kaku Gothic New','Hiragino Kaku Gothic ProN','Yu Gothic',sans-serif;
  background:
    radial-gradient(900px 600px at 12% 12%, rgba(247,183,166,0.55), transparent 60%),
    radial-gradient(800px 550px at 88% 18%, rgba(243,192,75,0.35), transparent 62%),
    linear-gradient(to bottom, var(--bg-primary) 0%, #ffeede 35%, var(--bg-secondary) 100%);
  color: var(--text-primary);
  padding: 20px;
}

/* ===== コンテナ ===== */

.container {
  max-width: 900px;
  margin: 0 auto;
  background: rgba(255,255,255,0.94);
  border-radius: 18px;
  box-shadow: var(--shadow-medium);
  overflow: hidden;
  border: 1px solid var(--border-light);
}

/* ===== ヘッダー ===== */

.header {
  position: relative;
  background:
    radial-gradient(900px 420px at 20% 25%, rgba(243,192,75,0.22), transparent 62%),
    linear-gradient(135deg, rgba(196,59,47,0.96), rgba(31,44,92,0.96));
  color: #ffffff;
  padding: 60px 40px;
  text-align: center;
}

.header::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 18% 65%, rgba(255,255,255,0.10) 0 2px, transparent 3px),
    radial-gradient(circle at 82% 38%, rgba(255,255,255,0.08) 0 2px, transparent 3px),
    radial-gradient(circle at 55% 25%, rgba(255,255,255,0.08) 0 2px, transparent 3px);
  opacity: 0.8;
}

.header-badge {
  display: inline-block;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.30);
  background: rgba(0,0,0,0.14);
  margin-bottom: 18px;
  font-size: 0.95rem;
  letter-spacing: 0.12em;
}

.app-title {
  font-family: 'Shippori Mincho','Yu Mincho',serif;
  font-size: clamp(2.2rem, 5vw, 3.0rem);
  letter-spacing: 0.12em;
}

.app-subtitle {
  margin-top: 18px;
  font-size: 1rem;
  letter-spacing: 0.18em;
  opacity: 0.92;
}

/* ===== コンテンツ ===== */

.content {
  padding: 50px;
}

.section {
  margin-bottom: 50px;
}

/* 見出し */

.section-title {
  font-family: 'Shippori Mincho','Yu Mincho',serif;
  font-size: 1.6rem;
  margin-bottom: 25px;
  padding-left: 18px;
  border-left: 5px solid var(--primary-color);
  color: var(--secondary-color);
}

/* ===== アプリ説明ブロック ===== */

.app-info {
  background:
    linear-gradient(to bottom, rgba(255,255,255,0.96), rgba(255,245,235,0.96));
  padding: 35px;
  border-radius: 14px;
  border: 1px solid rgba(180,200,220,0.45);
}

.app-info p {
  line-height: 1.9;
  margin-bottom: 14px;
  color: var(--text-secondary);
}

.description-content h4 {
  font-family: 'Shippori Mincho','Yu Mincho',serif;
  color: var(--primary-color);
  margin-top: 26px;
  margin-bottom: 10px;
  padding-left: 14px;
  border-left: 3px solid rgba(243,192,75,0.65);
}

.description-content p {
  margin-bottom: 0;
}

/* ===== 特徴リスト ===== */

.features-list {
  list-style: none;
  margin-top: 25px;
}

.features-list li {
  position: relative;
  padding-left: 42px;
  margin: 12px 0;
  color: var(--text-secondary);
  line-height: 1.7;
}

.features-list li::before {
  content: "👹";
  position: absolute;
  left: 0;
  top: 0;
}

/* ===== キーワード ===== */

.keyword-box {
  margin-top: 28px;
  padding: 22px 24px;
  border-radius: 14px;
  border: 1px solid rgba(31,44,92,0.18);
  background:
    radial-gradient(700px 260px at 12% 10%, rgba(247,183,166,0.35), transparent 60%),
    linear-gradient(to bottom, rgba(255,255,255,0.96), rgba(255,241,231,0.96));
}

.keyword-box h3 {
  font-family: 'Shippori Mincho','Yu Mincho',serif;
  color: var(--secondary-color);
  margin-bottom: 10px;
}

.keywords {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ===== 運営情報・問い合わせ ===== */

.company-info,
.contact-info {
  background:
    linear-gradient(to bottom, rgba(255,250,248,0.98), rgba(255,236,225,0.96));
  padding: 35px;
  border-radius: 14px;
  border: 1px solid rgba(180,200,220,0.45);
}

.company-info h3,
.contact-info h3 {
  font-family: 'Shippori Mincho','Yu Mincho',serif;
  color: var(--secondary-color);
  margin-bottom: 18px;
}

/* ===== 日付 ===== */

.date-info {
  margin-top: 40px;
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* ===== モバイル対応 ===== */

@media (max-width: 768px) {
  .content {
    padding: 30px;
  }

  .header {
    padding: 45px 22px;
  }

  .app-title {
    letter-spacing: 0.10em;
  }
}