/* ==========================================================================
   フロントページ専用スタイル - 杏書道教室
   common.css の CSS変数・リセットを前提とする
   ========================================================================== */

/* --------------------------------------------------------------------------
   ボタン
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 2rem;
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  border-radius: var(--radius-md);
  transition:
    background-color var(--transition),
    color var(--transition),
    transform var(--transition),
    box-shadow var(--transition);
  white-space: nowrap;
  text-decoration: none;
  cursor: pointer;
}

/* メインアプリコットボタン */
.btn--apricot {
  background-color: var(--color-apricot);
  color: #fff;
}
.btn--apricot:hover {
  background-color: var(--color-apricot-dark);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(200, 98, 58, 0.38);
}

/* 白ボタン（暗い背景の上で使用） */
.btn--white {
  background-color: #fff;
  color: var(--color-apricot);
}
.btn--white:hover {
  background-color: var(--color-bg-pale);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(255, 255, 255, 0.25);
}

/* ゴーストボタン（アプリコット枠線） */
.btn--ghost {
  background-color: transparent;
  color: var(--color-apricot);
  border: 2px solid var(--color-apricot);
}
.btn--ghost:hover {
  background-color: var(--color-apricot);
  color: #fff;
  transform: translateY(-2px);
}

/* --------------------------------------------------------------------------
   セクション共通
   -------------------------------------------------------------------------- */

/* 英字ラベル（セクション上部の小さなテキスト） */
.section-en {
  display: block;
  text-align: center;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--color-apricot);
  text-transform: uppercase;
  margin-bottom: 0.6rem;
}
.section-en--light {
  color: rgba(255, 255, 255, 0.65);
}

/* セクション見出し */
.section-title {
  font-size: clamp(1.4rem, 3vw, 1.9rem);
  font-weight: 700;
  color: var(--color-ink);
  text-align: center;
  letter-spacing: 0.04em;
  line-height: 1.5;
  margin-bottom: clamp(2rem, 4vw, 3.5rem);
}
.section-title--light {
  color: #fff;
}

/* パララックスセクション共通 */
.philosophy-section,
.courses-section,
.cta-section {
  position: relative;
  overflow: hidden;
}

/* パララックス背景レイヤー（CSS background-attachment: fixed） */
.parallax-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  z-index: 0;
}

@media (prefers-reduced-motion: reduce) {
  .parallax-bg {
    background-attachment: scroll;
  }
}

/* --------------------------------------------------------------------------
   1. ヒーロースライダー（16:9）
   -------------------------------------------------------------------------- */
.hero-slider {
  width: 100%;
  position: relative;
  overflow: hidden;
  /* 16:9 ratio: 56.25vw。最小400px、最大720px でクランプ */
  height: clamp(400px, 56.25vw, 720px);
  background-color: var(--color-dark);
}

/* スライドトラック：水平並び、CSS transitionでスライド */
.slider__track {
  display: flex;
  height: 100%;
  transition: transform 0.72s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.slider__slide {
  flex: 0 0 100%;
  height: 100%;
  position: relative;
  background-size: cover;
  background-position: center;
}

/* 暗めオーバーレイ（テキスト可読性確保） */
.slider__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(45, 37, 32, 0.70) 0%,
    rgba(45, 37, 32, 0.35) 55%,
    transparent 100%
  );
}

/* スライドコンテンツ（テキスト＋ボタン） */
.slider__content {
  position: relative;
  z-index: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: var(--header-h);
}

.slider__content .btn {
  width: 200px;
  justify-content: center;
}

/* 小さなラベルテキスト */
.slider__eyebrow {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: rgba(255, 255, 255, 0.72);
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

/* スライドタイトル（h1 または p） */
.slider__title {
  font-size: clamp(1.9rem, 5.5vw, 3.5rem);
  font-weight: 700;
  color: #fff;
  line-height: 1.35;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
  text-shadow:
    0 2px 8px rgba(0, 0, 0, 0.55),
    0 4px 24px rgba(0, 0, 0, 0.35);
}

/* サブテキスト */
.slider__sub {
  font-size: clamp(0.88rem, 2vw, 1.05rem);
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 2rem;
  letter-spacing: 0.03em;
  line-height: 1.75;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.5);
}

/* 前後ナビボタン */
.slider__btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.14);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.28);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition), border-color var(--transition);
  cursor: pointer;
}
.slider__btn:hover {
  background-color: rgba(255, 255, 255, 0.28);
  border-color: rgba(255, 255, 255, 0.5);
}
.slider__btn--prev { left: 1.25rem; }
.slider__btn--next { right: 1.25rem; }

/* ドットナビ */
.slider__dots {
  position: absolute;
  bottom: 1.25rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 10px;
  z-index: 10;
}
.slider__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.38);
  border: none;
  cursor: pointer;
  transition: background-color var(--transition), transform var(--transition);
  padding: 0;
}
.slider__dot.is-active {
  background-color: var(--color-apricot-light);
  transform: scale(1.45);
}

/* --------------------------------------------------------------------------
   2. 理念セクション（パララックス）
   -------------------------------------------------------------------------- */
.philosophy-section {
  min-height: 540px;
  display: flex;
  align-items: center;
}

.philosophy-overlay {
  position: absolute;
  inset: 0;
  background: rgba(45, 37, 32, 0.74);
  z-index: 1;
}

.philosophy-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding-block: var(--section-padding);
}

.philosophy-title {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.08em;
  line-height: 1.5;
  margin-bottom: 1.75rem;
}

.philosophy-body {
  font-size: clamp(0.9rem, 1.8vw, 1.05rem);
  color: rgba(255, 255, 255, 0.84);
  line-height: 2.1;
  letter-spacing: 0.04em;
}

/* 大きな装飾文字「杏」 */
.philosophy-deco {
  font-size: clamp(6rem, 16vw, 14rem);
  font-weight: 700;
  color: rgba(255, 255, 255, 0.045);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  letter-spacing: 0;
  z-index: 1;
  white-space: nowrap;
  line-height: 1;
}

/* --------------------------------------------------------------------------
   3. 特徴セクション
   -------------------------------------------------------------------------- */
.features-section {
  padding-block: var(--section-padding);
  background-color: var(--color-bg);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2rem;
}

.feature-card {
  text-align: center;
  padding: 2.5rem 2rem;
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-light);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}
.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.feature-card__icon {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background-color: var(--color-apricot-pale);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  color: var(--color-apricot);
}

.feature-card__title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-ink);
  letter-spacing: 0.04em;
  line-height: 1.6;
  margin-bottom: 0.85rem;
}

.feature-card__text {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--color-ink-mid);
  line-height: 1.9;
}

/* --------------------------------------------------------------------------
   4. コースセクション（パララックス）
   -------------------------------------------------------------------------- */
.courses-section {
  min-height: 640px;
}

.courses-overlay {
  position: absolute;
  inset: 0;
  background: rgba(45, 37, 32, 0.82);
  z-index: 1;
}

.courses-content {
  position: relative;
  z-index: 2;
  padding-block: var(--section-padding);
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 1.5rem;
}

.course-card {
  background-color: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius-lg);
  padding: 2rem 1.75rem;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: background-color var(--transition), transform var(--transition);
}
.course-card:hover {
  background-color: rgba(255, 255, 255, 0.13);
  transform: translateY(-4px);
}

.course-card__num {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-apricot-light);
  line-height: 1;
  margin-bottom: 0.75rem;
  letter-spacing: -0.02em;
}

.course-card__title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.04em;
  margin-bottom: 0.65rem;
}

.courses-grid .course-card__text {
  font-size: 0.85rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.74);
  line-height: 1.85;
}

/* --------------------------------------------------------------------------
   5. ギャラリーセクション
   -------------------------------------------------------------------------- */
.gallery-section {
  padding-block: var(--section-padding);
  background-color: var(--color-bg-pale);
}

.gallery-note {
  text-align: center;
  font-size: 0.82rem;
  color: var(--color-ink-muted);
  margin-top: -1.75rem;
  margin-bottom: 2rem;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
}

.gallery-item {
  border-radius: var(--radius-md);
  overflow: hidden;
  aspect-ratio: 3 / 2;
}
.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
  display: block;
}
.gallery-item:hover img {
  transform: scale(1.06);
}

/* --------------------------------------------------------------------------
   6. 体験レッスン CTA（パララックス）
   -------------------------------------------------------------------------- */
.cta-section {
  min-height: 480px;
  display: flex;
  align-items: center;
}

.cta-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(168, 78, 44, 0.88) 0%,
    rgba(45, 37, 32, 0.72) 100%
  );
  z-index: 1;
}

.cta-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding-block: var(--section-padding);
}

.cta-title {
  font-size: clamp(1.7rem, 4.5vw, 2.6rem);
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.06em;
  line-height: 1.45;
  margin-bottom: 1rem;
}

.cta-body {
  font-size: clamp(0.9rem, 1.8vw, 1rem);
  color: rgba(255, 255, 255, 0.86);
  line-height: 2;
  margin-bottom: 2rem;
}

/* --------------------------------------------------------------------------
   7. ニュースセクション
   -------------------------------------------------------------------------- */
.news-section {
  padding-block: var(--section-padding);
  background-color: var(--color-bg);
}

.news-list {
  border-top: 1px solid var(--color-border);
  margin-bottom: 2.5rem;
}

.news-item {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--color-border-light);
  flex-wrap: wrap;
}

.news-date {
  font-size: 0.82rem;
  color: var(--color-ink-muted);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  flex-shrink: 0;
}

.news-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  flex-shrink: 0;
}
.label-news {
  background-color: var(--color-apricot-pale);
  color: var(--color-apricot);
  border: 1px solid var(--color-apricot-light);
}
.label-blog {
  background-color: var(--color-accent2-light);
  color: var(--color-accent2);
  border: 1px solid var(--color-accent2-light);
}

.news-title {
  font-size: 0.9rem;
  color: var(--color-ink);
  line-height: 1.65;
  transition: color var(--transition);
}
.news-title:hover {
  color: var(--color-apricot);
}

.news-empty {
  padding: 2rem 0;
  color: var(--color-ink-muted);
  text-align: center;
  font-size: 0.9rem;
}

.news-more {
  text-align: center;
}

/* --------------------------------------------------------------------------
   スクロールフェードイン（IntersectionObserver で .is-visible を付与）
   -------------------------------------------------------------------------- */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}
.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* --------------------------------------------------------------------------
   レスポンシブ
   -------------------------------------------------------------------------- */
@media (min-width: 768px) {
  .gallery-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .slider__btn {
    width: 56px;
    height: 56px;
  }
}

@media (max-width: 599px) {
  /* スマホではスライドの前後ボタンを非表示（スワイプで代替） */
  .slider__btn {
    display: none;
  }

  .news-item {
    gap: 0.5rem;
  }
}