:root {
    --bg-dark: #121212;
    --bg-card: #282828;
    --text-main: #FFFFFF;
    --text-sub: #AAAAAA;
    --accent: #FF007F;
    --accent-orange: #FF6F00;
}

body {
    margin: 0;
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
    display: block;
}

img {
    max-width: 100%;
    height: auto;
}

ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

/* ヘッダー / ファーストビュー */
.hero {
    position: relative;
    width: 100%;
    height: 100vh;
    overflow: hidden;
    color: #FFFFFF;
}

.hero-bg-spacer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('/images/lp05-hero_bg_sp.png');
    background-size: cover;
    background-position: center;
    z-index: 1;
}

.header-top {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    box-sizing: border-box;
    z-index: 20;
}

.logo-container img {
    height: 40px;
    opacity: 0;
}

.header-cta {
    display: flex;
    align-items: center;
}

/* ハンバーガーボタン */
.hamburger {
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    width: 30px;
    height: 24px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    z-index: 30;
}

.hamburger span {
    display: block;
    width: 100%;
    height: 3px;
    background-color: #FFFFFF;
    border-radius: 2px;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: translateY(10px) rotate(45deg);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: translateY(-11px) rotate(-45deg);
}

/* ドロワーメニュー */
.drawer-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    background-color: rgba(18, 18, 18, 0.95);
    backdrop-filter: blur(10px);
    z-index: 25;
    padding: 80px 30px 30px;
    box-sizing: border-box;
    transition: right 0.3s ease;
}

.drawer-menu.active {
    right: 0;
}

.drawer-close {
    position: absolute;
    top: 20px;
    right: 20px;
    background: none;
    border: none;
    color: #FFFFFF;
    font-size: 24px;
    cursor: pointer;
    z-index: 35;
    transition: color 0.3s;
}

.drawer-close:hover {
    color: var(--accent);
}

.drawer-menu ul li {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.drawer-menu ul li a {
    padding: 15px 0;
    font-size: 16px;
    font-weight: bold;
    color: var(--text-main);
    display: flex;
    align-items: center;
}

.icon-menu {
    width: 24px;
    margin-right: 10px;
    color: var(--accent);
    text-align: center;
}

/* ヒーローコンテンツエリア */
.hero-content {
    position: absolute;
    bottom: 12%;                 /* 画面下部から12%の位置に配置 */
    left: 50%;                   /* 画面の左端から50%の位置へ移動 */
    transform: translateX(-50%); /* 自身の幅の半分だけ左に押し戻して完全中央揃え */
    width: 100%;                 /* 幅を100%確保 */
    max-width: 400px;            /* ボタン幅が広がりすぎないよう制限 */
    padding: 0 20px;             /* 端の切れ防止用の左右余白 */
    box-sizing: border-box;      /* パディングを含めた幅計算にする設定 */
    z-index: 15;
    text-align: center;          /* 内部要素を中央揃え */
    display: flex;
    flex-direction: column;
    align-items: center;         /* Flexboxによる中央揃え */
}

/* 会員登録ボタン */
.btn-register-hero {
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-orange) 100%);
    color: #FFFFFF;
    padding: 14px 0;             /* 上下パディングを指定（左右はwidthで制御） */
    width: 100%;                 /* hero-contentの幅いっぱいに広げる */
    max-width: 320px;            /* ボタン自体の最大幅を設定 */
    border-radius: 30px;
    font-size: 18px;
    font-weight: bold;
    display: inline-flex;
    justify-content: center;     /* アイコンとテキストをボタンの中央に配置 */
    align-items: center;
    gap: 10px;
    box-shadow: 0 4px 15px rgba(255, 0, 127, 0.4);
    transition: transform 0.2s, box-shadow 0.2s;
    box-sizing: border-box;
}

.btn-register-hero:hover {
    transform: translateY(-2px) scale(1.03);
    box-shadow: 0 6px 20px rgba(255, 0, 127, 0.6);
}

/* ランダム浮遊サムネイル */
.floating-thumbnails {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 8;
}

.thumb-card {
    position: absolute;
    width: 65px;
    height: 65px;
    background-color: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.5);
    animation: floatAnimation 4s ease-in-out infinite alternate;
    pointer-events: auto;
    transition: filter 0.2s;
    overflow: hidden;
}

.thumb-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.thumb-card:hover {
    filter: brightness(1.2);
}

@keyframes floatAnimation {
    0% {
        transform: translateY(0px) rotate(var(--base-deg));
    }
    100% {
        transform: translateY(-10px) rotate(calc(var(--base-deg) + 4deg));
    }
}

#particle-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 5;
    pointer-events: none;
}

.particle {
    position: absolute;
    background-color: #FFFFFF;
    border-radius: 50%;
    opacity: 0;
}

/* メインコンテンツ */
.music-section {
    padding: 40px 20px;
}

.bg-dark {
    background-color: #000000;
}

.section-title {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: 20px;
    padding-left: 10px;
    border-left: 4px solid var(--accent);
    display: flex;
    align-items: center;
    gap: 8px;
}

.section-title i {
    color: var(--accent);
}

/* 横スクロール対応 */
.music-grid {
    display: flex;
    overflow-x: auto;
    gap: 15px;
    padding-bottom: 15px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
    scrollbar-color: var(--accent) #1a1a1a;
}

.music-grid::-webkit-scrollbar {
    height: 6px;
}

.music-grid::-webkit-scrollbar-track {
    background: #1a1a1a;
    border-radius: 10px;
}

.music-grid::-webkit-scrollbar-thumb {
    background: linear-gradient(90deg, var(--accent) 0%, var(--accent-orange) 100%);
    border-radius: 10px;
    box-shadow: 0 0 8px rgba(255, 0, 127, 0.6);
}

.music-card {
    flex: 0 0 calc(33% - 10px);
    display: flex;
    flex-direction: column;
}

.thumb-link {
    position: relative;
    width: 100%;
}

.thumb-link .thumb {
    position: relative;
    width: 100%;
    padding-top: 100%;
    background-color: var(--bg-card);
    border-radius: 8px;
    margin-bottom: 8px;
    transition: transform 0.2s;
    overflow: hidden;
}

.thumb-link .thumb img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    z-index: 1;
}

.thumb-link .thumb i.fa-play {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 24px;
    color: #FFFFFF;
    opacity: 0;
    transition: opacity 0.3s ease, transform 0.3s ease;
    z-index: 2;
    pointer-events: none;
}

.thumb-link:hover .thumb {
    transform: scale(1.03);
}

.thumb-link:hover .thumb i.fa-play {
    opacity: 0.6;
    transform: translate(-50%, -50%) scale(1.1);
}

.rank-badge {
    position: absolute;
    top: 0;
    left: 0;
    background: rgba(0, 0, 0, 0.7);
    color: #FFFFFF;
    font-weight: bold;
    font-size: 11px;
    padding: 3px 8px;
    border-top-left-radius: 8px;
    border-bottom-right-radius: 8px;
    display: flex;
    align-items: center;
    gap: 4px;
    z-index: 3;
}

.rank-badge.rank-1 {
    background: linear-gradient(135deg, #FFD700 0%, #FF8C00 100%);
    color: #000;
}

.rank-badge.rank-2 {
    background: linear-gradient(135deg, #E0E0E0 0%, #888888 100%);
    color: #000;
}

.rank-badge.rank-3 {
    background: linear-gradient(135deg, #C47222 0%, #6E3B07 100%);
    color: #FFF;
}

.info-link {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.info-link:hover {
    opacity: 0.8;
}

.info-link .title {
    font-size: 13px;
    font-weight: bold;
    color: var(--text-main);
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.info-link .artist {
    font-size: 11px;
    color: var(--text-sub);
    display: flex;
    align-items: center;
    gap: 4px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.info-link .artist i {
    font-size: 10px;
}

.info-link .desc {
    font-size: 10px;
    color: #888888;
    margin-top: 4px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.3;
}

.recommend-card {
    flex: 0 0 calc(45% - 10px);
}

/* ジャンル＆検索 */
.genre-search-section {
    padding: 40px 20px;
}

.genre-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    margin-bottom: 30px;
}

.genre-item {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    height: 60px;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-orange) 100%);
    border-radius: 8px;
    font-weight: bold;
    color: #FFFFFF;
}

.search-box {
    width: 100%;
}

.search-form {
    display: flex;
    align-items: center;
    border: 1px solid #555555;
    border-radius: 25px;
    background-color: #1a1a1a;
    padding: 5px 15px;
}

.search-input {
    flex: 1;
    background: none;
    border: none;
    color: #FFFFFF;
    font-size: 16px;
    padding: 10px 0;
}

.search-input:focus {
    outline: none;
}

.search-submit {
    background: none;
    border: none;
    color: var(--text-sub);
    cursor: pointer;
    font-size: 16px;
    padding: 5px;
    transition: color 0.2s;
}

.search-submit:hover {
    color: var(--accent);
}

/* フッター */
.footer {
    background-color: #000000;
    padding: 40px 20px;
    text-align: center;
    font-size: 14px;
    color: var(--text-sub);
}

.footer-menu {
    margin-bottom: 30px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.footer-menu li a {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 5px 0;
}

.footer-menu li a i {
    font-size: 12px;
    color: var(--text-sub);
}

.license-info {
    margin-bottom: 30px;
    line-height: 1.8;
}

.license-info i {
    color: var(--accent);
    margin-right: 4px;
}

.copyright {
    font-size: 12px;
    margin-top: 20px;
}

/* アニメーション */
@keyframes logoFlash {
    0% { filter: brightness(100%) drop-shadow(0 0 0px #fff); }
    10% { filter: brightness(200%) drop-shadow(0 0 10px #fff); }
    20% { filter: brightness(100%) drop-shadow(0 0 0px #fff); }
}

#header-logo.active {
    opacity: 1;
    animation: logoFlash 1s ease-in-out;
}

@keyframes particleFadeOut {
    0% { transform: translateY(0) scale(1); opacity: 1; }
    100% { transform: translateY(-100px) scale(0); opacity: 0; }
}

/* PCレスポンシブ対応 */
@media (min-width: 768px) {
    .hero-bg-spacer {
        background-image: url('/images/lp05-hero_bg_pc.png');
    }

    .music-grid {
        flex-wrap: wrap;
        gap: 20px;
    }

    .music-card {
        flex: 0 0 calc(20% - 16px);
    }

    .recommend-card {
        flex: 0 0 calc(20% - 16px);
    }

    .genre-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-menu {
        grid-template-columns: repeat(4, 1fr);
    }
}