/* ============================================
   グローバルリセットとベーススタイル
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
    padding: 20px 0;
    transition: background 0.5s ease;
}

/* ============================================
   波のアニメーション背景
   ============================================ */
.wave {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 120"><path fill="%23ffffff" fill-opacity="0.1" d="M0,0 Q300,50 600,0 T1200,0 L1200,120 L0,120 Z"><animate attributeName="d" dur="10s" repeatCount="indefinite" values="M0,0 Q300,50 600,0 T1200,0 L1200,120 L0,120 Z;M0,0 Q300,0 600,50 T1200,0 L1200,120 L0,120 Z;M0,0 Q300,50 600,0 T1200,0 L1200,120 L0,120 Z"/></path></svg>') repeat-x;
    animation: wave 15s linear infinite;
    opacity: 0.3;
    pointer-events: none;
    z-index: 1;
}

.wave:nth-child(2) {
    animation: wave 20s linear infinite reverse;
    opacity: 0.2;
}

.wave:nth-child(3) {
    animation: wave 25s linear infinite;
    opacity: 0.1;
}

@keyframes wave {
    0% { background-position-x: 0; }
    100% { background-position-x: 1200px; }
}

/* ============================================
   浮遊する絵文字アニメーション
   ============================================ */
.floating-emoji {
    position: fixed;
    font-size: 3rem;
    animation: float 6s ease-in-out infinite;
    opacity: 0.6;
    pointer-events: none;
    z-index: 2;
}

.floating-emoji:nth-child(4) { top: 10%; left: 10%; animation-delay: 0s; }
.floating-emoji:nth-child(5) { top: 20%; right: 15%; animation-delay: 1s; }
.floating-emoji:nth-child(6) { top: 60%; left: 20%; animation-delay: 2s; }
.floating-emoji:nth-child(7) { bottom: 20%; right: 20%; animation-delay: 3s; }
.floating-emoji:nth-child(8) { top: 70%; right: 10%; animation-delay: 1.5s; }
.floating-emoji:nth-child(9) { top: 40%; left: 5%; animation-delay: 2.5s; }

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    25% { transform: translateY(-20px) rotate(5deg); }
    50% { transform: translateY(-10px) rotate(-5deg); }
    75% { transform: translateY(-15px) rotate(3deg); }
}

/* ============================================
   パーティクル効果（泡）
   ============================================ */
.particles {
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
    z-index: 1;
}

.particle {
    position: absolute;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0.4) 50%, rgba(255, 255, 255, 0) 100%);
    border-radius: 50%;
    animation: bubble-float linear infinite;
    opacity: 0;
}

@keyframes bubble-float {
    0% {
        transform: translateY(0) translateX(0) scale(0);
        opacity: 0;
    }
    10% {
        opacity: 0.8;
        transform: translateY(-10vh) translateX(5px) scale(1);
    }
    50% {
        opacity: 0.6;
    }
    100% {
        transform: translateY(-100vh) translateX(-20px) scale(0.5);
        opacity: 0;
    }
}

/* ============================================
   メインコンテナとレイアウト
   ============================================ */
.container {
    position: relative;
    z-index: 10;
    max-width: 1400px;
    margin: 0 auto;
    padding: 40px 20px 60px;
    animation: fadeIn 1s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* ============================================
   タイトルとヘッダースタイル
   ============================================ */
/* サーフィンアイコン（タイトル上） */
.logo-icon {
    text-align: center;
    font-size: 6rem;
    margin-bottom: 20px;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

h1 {
    text-align: center;
    font-size: 3.5rem;
    font-weight: bold;
    color: white;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    margin-bottom: 40px;
    animation: fadeInDown 1s ease-out;
}

.subtitle {
    font-size: 1.8rem;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 30px;
    text-align: center;
    animation: fadeIn 1.5s ease-out;
}

.description {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.8;
    margin: 30px auto 50px;
    max-width: 600px;
    animation: fadeIn 2.5s ease-out;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ============================================
   カテゴリナビゲーション
   ============================================ */
.category-navigation {
    text-align: left;
    margin: 30px 0 50px;
    padding: 25px;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: fadeIn 1.5s ease-out;
}

.category-label {
    font-size: 1.1rem;
    font-weight: 600;
    color: white;
    margin-right: 15px;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.category-select {
    padding: 12px 20px;
    font-size: 1rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.95);
    color: #333;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.category-select:hover {
    background: white;
    border-color: rgba(255, 255, 255, 0.5);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.category-select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.3);
}

/* ============================================
   製品グループとグリッド
   ============================================ */
.product-group {
    margin-bottom: 60px;
    padding: 30px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: fadeIn 2s ease-out;
}

.group-title {
    font-size: 2rem;
    font-weight: bold;
    color: white;
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 15px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.category-icon {
    font-size: 2.5rem;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 25px;
}

/* ============================================
   製品カードスタイル
   ============================================ */
.product-card {
    background: rgba(255, 255, 255, 0.95);
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    background: white;
}

.product-card.empty {
    background: transparent;
    box-shadow: none;
    border: 2px dashed rgba(255, 255, 255, 0.3);
    min-height: 200px;
}

.product-card.empty:hover {
    transform: none;
    box-shadow: none;
}

.product-image {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: 10px;
    margin-bottom: 20px;
}

.product-title {
    font-size: 1.5rem;
    font-weight: bold;
    color: #333;
    margin-bottom: 15px;
}

.product-description {
    font-size: 0.95rem;
    color: #666;
    line-height: 1.7;
    margin-bottom: 20px;
    flex-grow: 1;
}

/* ============================================
   リンクとボタンスタイル
   ============================================ */
.detail-link {
    display: inline-block;
    padding: 12px 25px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
}

.detail-link:hover {
    background: linear-gradient(135deg, #764ba2, #667eea);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.detail-link.disabled {
    background: #ccc;
    color: #666;
    cursor: not-allowed;
    pointer-events: none;
}

/* ============================================
   フッター
   ============================================ */
.footer {
    text-align: center;
    padding: 40px 20px;
    margin-top: 60px;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    position: relative;
    z-index: 10;
    animation: fadeIn 2.5s ease-out;
}

.footer-text {
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.footer-text strong {
    background: linear-gradient(135deg, #fff 0%, #f0f0f0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: 1.2rem;
}

.footer-copyright {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.8);
}

/* ============================================
   トップへ戻るボタン
   ============================================ */
#back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
}

#back-to-top.show {
    opacity: 1;
    visibility: visible;
}

#back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.5);
}

/* ============================================
   レスポンシブデザイン
   ============================================ */
@media (max-width: 1024px) {
    .grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
        gap: 20px;
    }
}

@media (max-width: 768px) {
    body {
        padding: 10px 0;
    }

    .logo-icon {
        font-size: 4rem;
        margin-bottom: 15px;
    }

    h1 {
        font-size: 2.5rem;
        margin-bottom: 30px;
    }

    .container {
        padding: 20px 15px 40px;
    }

    .category-navigation {
        padding: 20px;
        margin: 20px 0 30px;
    }

    .category-label {
        display: block;
        margin-bottom: 10px;
        margin-right: 0;
    }

    .category-select {
        width: 100%;
        padding: 10px 15px;
    }

    .product-group {
        padding: 20px;
        margin-bottom: 40px;
    }

    .group-title {
        font-size: 1.5rem;
        gap: 10px;
    }

    .category-icon {
        font-size: 2rem;
    }

    .grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .floating-emoji {
        font-size: 2rem;
    }

    #back-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
        font-size: 1.3rem;
    }

    .footer {
        padding: 30px 15px;
        margin-top: 40px;
    }
}

@media (max-width: 480px) {
    .logo-icon {
        font-size: 3rem;
    }

    h1 {
        font-size: 2rem;
    }

    .group-title {
        font-size: 1.3rem;
    }

    .product-title {
        font-size: 1.3rem;
    }

    .product-description {
        font-size: 0.9rem;
    }
}

/* ［Kindle Unlimited］の読み放題（初回体験あり） */
.ku-cta--glass{
  display:inline-block; padding:.5em .8em; border-radius:.75rem;
  background: rgba(255,255,255,.18); color:#0b1220;
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
  border:1px solid rgba(255,255,255,.35);
}
.ku-cta--glass:hover{ background: rgba(255,255,255,.24); }
.ku-cta--glass:focus-visible{ outline:2px solid #fff; outline-offset:2px; }

/* NEW リリース バッジ (クラシック赤バージョン) */
.new-badge {
    display: inline-block;
    background: linear-gradient(135deg, #ff416c 0%, #ff4b2b 100%);
    color: white;
    font-size: 0.65rem;
    font-weight: bold;
    padding: 5px 12px;
    border-radius: 20px;
    letter-spacing: 0.5px;
    box-shadow: 0 3px 10px rgba(255, 65, 108, 0.5);
    animation: wave-badge 2s ease-in-out infinite;
    position: relative;
}

.new-badge::after {
    content: '✨';
    position: absolute;
    right: -5px;
    top: -8px;
    font-size: 1rem;
    animation: sparkle-badge 1.5s ease-in-out infinite;
}

/* アップデート バッジ (パープルバージョン) */
.update-badge {
    display: inline-block;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-size: 0.65rem;
    font-weight: bold;
    padding: 5px 12px;
    border-radius: 20px;
    letter-spacing: 0.5px;
    box-shadow: 0 3px 10px rgba(102, 126, 234, 0.5);
    animation: wave-badge 2s ease-in-out infinite;
    position: relative;
}

.update-badge::after {
    content: '✨';
    position: absolute;
    right: -5px;
    top: -8px;
    font-size: 1rem;
    animation: sparkle-badge 1.5s ease-in-out infinite;
}

@keyframes wave-badge {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-3px); }
}

@keyframes sparkle-badge {
    0%, 100% { opacity: 0; transform: scale(0.8); }
    50% { opacity: 1; transform: scale(1.2); }
}