:root {
  --bg-color: #0d0e15;
  --card-bg: rgba(255, 255, 255, 0.05);
  --accent-color: #0088ff; /* 青系メインカラー */
  --accent-blue: #00f2fe;  /* 青系サブ（アクセント） */
  --text-main: #ffffff;
  --text-sub: #a0a0b0;
}

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

html {
  scroll-behavior: smooth;
  font-family: 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: #0d0e15;
}
::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--accent-color), var(--accent-blue));
  border-radius: 4px;
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.3s ease;
}

/* imgタグスタイル */
.img-logo {
  height: 36px;
  object-fit: cover;
  display: block;
  border-radius: 4px;
}

.img-thumb {
  width: 100%;
  height: 100%;
  aspect-ratio: 1/1;
  object-fit: cover;
  display: block;
  border-radius: 6px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

/* ヒーローエリア */
.hero {
  position: relative;
  width: 100%;
  height: 80vh;
  min-height: 500px;
  background: url('/images/lp04-hero_bg_sp.jpg') center center / cover no-repeat;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
  padding-bottom: 20px;
}

/* PC用背景画像切り替え（画面幅768px以上） */
@media (min-width: 768px) {
  .hero {
    background-image: url('/images/lp04-hero_bg_pc.jpg');
  }
}

/* 青系の動的グラデーションオーバーレイ */
.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  /* ベースの闇色 ＋ 動き回る鮮やかなブルー・シアンの光 */
  background: linear-gradient(
    -120deg,
    rgba(13, 14, 21, 0.75) 0%,
    rgba(0, 136, 255, 0.35) 35%,
    rgba(0, 242, 254, 0.25) 65%,
    rgba(13, 14, 21, 0.9) 100%
  );
  background-size: 200% 200%;
  animation: slowGlow 5s ease infinite alternate; /* 20秒かけてゆるやかに往復 */
  z-index: 1;
}

/* 光のゆらぎアニメーション */
@keyframes slowGlow {
  0% {
    background-position: 0% 0%;
  }
  50% {
    background-position: 100% 100%;
  }
  100% {
    background-position: 0% 100%;
  }
}

.header-bar {
  position: relative;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 20px;
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 12px;
}

.hamburger-btn {
  background: none;
  border: none;
  color: #fff;
  font-size: 28px;
  cursor: pointer;
  padding: 8px;
  z-index: 20;
  transition: transform 0.2s ease, color 0.2s ease;
}

.hamburger-btn:hover {
  color: var(--accent-blue);
  transform: scale(1.1);
}

/* 大型会員登録ボタン（青グラデーション） */
.hero-action-area {
  position: relative;
  z-index: 10;
  width: 100%;
  padding: 0 20px;
  display: flex;
  justify-content: center;
  margin-top: auto;
  margin-bottom: 25px;
}

.btn-register-main {
  width: 100%;
  max-width: 340px;
  min-height: 54px;
  background: linear-gradient(45deg, #ff9900, #ff5500);
  color: #ffffff;
  font-size: 18px;
  font-weight: bold;
  letter-spacing: 2px;
  border-radius: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 20px rgba(255, 85, 0, 0.5);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn-register-main:hover,
.btn-register-main:active {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 25px rgba(255, 85, 0, 0.7);
  background: linear-gradient(45deg, #ffaa11, #ff6611);
}

/* スライダー */
.hero-slider-container {
  position: relative;
  z-index: 10;
  width: 100%;
  padding-top: 15px;
  padding-bottom: 30px;
  overflow: hidden;
}

.hero-slider-track {
  display: flex;
  width: calc(150px * 12);
  animation: scroll 25s linear infinite;
  align-items: center;
}

.slide-item {
  width: 130px;
  margin: 0 10px;
  flex-shrink: 0;
}

.slide-item .img-thumb {
  transform-origin: center center;
}

.slide-item a:hover .img-thumb {
  transform: scale(1.08);
  border-color: var(--accent-blue);
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.5);
}

/* 上下スライダーの余白調整 */
.hero-slider-container.slider-top {
  padding-top: 10px;
  padding-bottom: 10px;
}

.hero-slider-container.slider-bottom {
  padding-top: 10px;
  padding-bottom: 10px;
}

.hero-action-area {
  margin-top: 10px;
  margin-bottom: 10px;
}

/* 逆回転用トラック設定 */
.hero-slider-reverse {
  animation: scroll-reverse 25s linear infinite;
}

/* 正回転アニメーション（既存） */
@keyframes scroll {
  0% { transform: translateX(0); }
  100% { transform: translateX(calc(-150px * 6)); }
}

/* 逆回転アニメーション（追加） */
@keyframes scroll-reverse {
  0% { transform: translateX(calc(-150px * 6)); }
  100% { transform: translateX(0); }
}

/* ハンバーガーメニュー */
.menu-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  z-index: 998;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.menu-overlay.active {
  opacity: 1;
  visibility: visible;
}

.drawer-menu {
  position: fixed;
  top: 0;
  right: -100%;
  width: 85%;
  max-width: 320px;
  height: 100%;
  background: #141521;
  z-index: 999;
  padding: 70px 0 20px 0;
  transition: right 0.3s ease;
  box-shadow: -5px 0 25px rgba(0,0,0,0.8);
}

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

.close-btn {
  background: none;
  border: none;
  color: #fff;
  font-size: 32px;
  position: absolute;
  top: 15px;
  right: 20px;
  cursor: pointer;
  padding: 10px;
  transition: transform 0.2s ease, color 0.2s ease;
}

.close-btn:hover {
  color: var(--accent-color);
  transform: rotate(90deg);
}

.menu-list {
  list-style: none;
  width: 100%;
}

.menu-list li {
  width: 100%;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.menu-list a {
  font-size: 16px;
  font-weight: bold;
  display: flex;
  align-items: center;
  width: 100%;
  padding: 20px 25px;
  box-sizing: border-box;
  transition: background 0.2s ease, padding-left 0.2s ease, color 0.2s ease;
}

.menu-list a:hover, .menu-list a:active {
  background: rgba(0, 136, 255, 0.15);
  padding-left: 32px;
  color: var(--accent-blue);
}

.menu-list a i {
  margin-right: 15px;
  width: 24px;
  text-align: center;
  font-size: 18px;
}

/* メインコンテンツ */
.container {
  padding: 20px 15px;
  max-width: 1000px;
  margin: 0 auto;
}

.section {
  margin-bottom: 40px;
}

.section-title-wrap {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
}

.section-title {
  font-size: 18px;
  border-left: 4px solid var(--accent-color);
  padding-left: 10px;
  margin-bottom: 15px; /* 全てのh2の下に余白を設定 */
}

.section-title-wrap .section-title {
  margin-bottom: 0;
}

.btn-more {
  font-size: 13px;
  font-weight: bold;
  color: var(--accent-blue);
  background: rgba(0, 136, 255, 0.1);
  border: 1px solid rgba(0, 136, 255, 0.3);
  padding: 6px 14px;
  border-radius: 16px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s ease;
}

.btn-more i {
  font-size: 10px;
  transition: transform 0.2s ease;
}

.btn-more:hover, .btn-more:active {
  background: var(--accent-color);
  color: #ffffff;
  border-color: var(--accent-color);
  box-shadow: 0 4px 12px rgba(0, 136, 255, 0.4);
}

.btn-more:hover i, .btn-more:active i {
  transform: translateX(3px);
}

.grid-layout {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

@media (min-width: 768px) {
  .grid-layout {
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
  }
}

.card {
  background: var(--card-bg);
  border-radius: 8px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  border: 1px solid rgba(255, 255, 255, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 136, 255, 0.5);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4), 0 0 10px rgba(0, 136, 255, 0.25);
}

.thumb-link {
  display: block;
  position: relative;
  width: 100%;
  aspect-ratio: 1/1;
  overflow: hidden;
}

.card:hover .thumb-link .img-thumb {
  transform: scale(1.05);
  border-color: var(--accent-blue);
}

.info-link {
  padding: 12px;
  display: block;
  flex-grow: 1;
}

.song-title {
  font-size: 13px;
  font-weight: bold;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color 0.2s ease;
}

.card:hover .song-title {
  color: var(--accent-blue);
}

.artist-name {
  font-size: 11px;
  color: var(--text-sub);
  margin-top: 4px;
}

.song-desc {
  font-size: 10px;
  color: #888899;
  margin-top: 6px;
  line-height: 1.3;
}

.rank-card {
  position: relative;
}

.rank-badge {
  position: absolute;
  top: 5px;
  left: 5px;
  background: rgba(0,0,0,0.8);
  color: #fff;
  font-weight: bold;
  font-size: 12px;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  z-index: 2;
}

.rank-1 { background: #ffd700; color: #000; }
.rank-2 { background: #c0c0c0; color: #000; }
.rank-3 { background: #c47222; color: #fff; }

.fixed-width-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  width: 100%;
}

.btn-fixed {
  width: calc(50% - 6px);
  box-sizing: border-box;
  text-align: center;
  background: var(--card-bg);
  border: 1px solid rgba(255,255,255,0.15);
  padding: 16px 10px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: bold;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: block;
  transition: transform 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.btn-fixed:hover, .btn-fixed:active {
  background: rgba(0, 136, 255, 0.15);
  border-color: var(--accent-blue);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 136, 255, 0.3);
}

@media (min-width: 768px) {
  .btn-fixed {
    width: calc(25% - 9px);
  }
}

.search-box form {
  margin-top: 20px;
  display: flex;
  gap: 8px;
}

.search-box input[type="text"] {
  flex-grow: 1;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.2);
  padding: 12px 18px;
  border-radius: 25px;
  color: #fff;
  font-size: 14px;
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.search-box input[type="text"]:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 10px rgba(0, 242, 254, 0.3);
}

.search-box button {
  background: var(--accent-color);
  border: none;
  color: #fff;
  padding: 0 22px;
  border-radius: 25px;
  cursor: pointer;
  font-size: 16px;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.search-box button:hover {
  background: #1a96ff;
  transform: scale(1.05);
}

.footer {
  background: #06060a;
  padding: 30px 15px;
  font-size: 12px;
  color: var(--text-sub);
  border-top: 1px solid rgba(255,255,255,0.05);
}

.footer-nav {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  width: 100%;
  margin-bottom: 30px;
}

.footer-nav li {
  width: calc(50% - 5px);
  box-sizing: border-box;
}

.footer-nav a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  min-height: 48px;
  padding: 10px;
  background: var(--card-bg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 6px;
  box-sizing: border-box;
  text-align: center;
  font-size: 12px;
  color: #d0d0e0;
  transition: transform 0.2s ease, background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.footer-nav a:hover, .footer-nav a:active {
  background: rgba(0, 136, 255, 0.2);
  border-color: var(--accent-color);
  color: #ffffff;
  transform: translateY(-2px);
}

@media (min-width: 768px) {
  .footer-nav li {
    width: calc(25% - 8px);
  }
}

.license-info {
  border-top: 1px solid rgba(255,255,255,0.05);
  padding-top: 20px;
  margin-bottom: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: center;
  line-height: 1.6;
}

.copyright {
  text-align: center;
  font-size: 10px;
}