/* ==============================================
   ISSEIKI 学習椅子LP - スタイルシート
   ============================================== */

/* --------------------------
   1. LP独自設定（変数・上書き）
   -------------------------- */
:root {
    /* LP独自のカラーパレット */
    --color-cream: #faf8f5;
    --color-beige: #f5f0e8;
    --color-beige-dark: #e8e0d5;
    --color-brown-light: #d4c4b0;
    --color-brown: #8b7355;
    --color-brown-dark: #5c4a3a;

    /* 共通CSSにあってLPでも使う変数はそのまま利用（--color-textなど） */
    /* 足りないものだけ再定義 */

    /* フォント */
    --font-primary: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "メイリオ", sans-serif;
    --font-serif: "Noto Serif JP", "游明朝", "YuMincho", serif;

    /* シリーズ別アクセントカラー */
    --series-a-color: #7b8e6e;
    --series-a-bg: #f0f4ed;
    --series-b-color: #6e7f8e;
    --series-b-bg: #edf1f4;
    --series-c-color: #8e7b6e;
    --series-c-bg: #f4f0ed;

    /* サイズ */
    --lp-container-max: 1000px;
    --section-padding: 80px 20px;
    --section-padding-mobile: 50px 16px;
}

/* 共通CSSのコンテナ幅をLP用に上書き */
.study-chair-lp .container {
    max-width: var(--lp-container-max);
    margin: 0 auto;
    padding: 0 20px;
}

/* リンクの基本スタイル（共通CSSになければ） */
.study-chair-lp a:hover {
    opacity: 0.8;
}

/* --------------------------
   LP独自コンポーネント
   -------------------------- */
.section-title {
    font-family: "Noto Serif JP", serif;
    font-size: 1.6rem;
    font-weight: 500;
    text-align: center;
    margin-bottom: 40px;
    color: var(--color-brown-dark);
    letter-spacing: 0.1em;
}

.section-title-en {
    display: block;
    font-family: "Noto Sans JP", sans-serif;
    font-size: 0.7rem;
    color: var(--color-accent);
    margin-bottom: 6px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    font-weight: 400;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    background-color: var(--color-brown);
    color: var(--color-white);
    border-radius: 4px;
    font-size: 0.95rem;
    font-weight: 500;
    letter-spacing: 0.05em;
    transition: background-color 0.3s ease, transform 0.2s ease;
    text-decoration: none;
}

.btn-primary:hover {
    background-color: var(--color-brown-dark);
    opacity: 1;
    transform: translateY(-2px);
}

.btn-primary svg {
    width: 18px;
    height: 18px;
    transition: transform 0.3s ease;
}

.btn-primary:hover svg {
    transform: translateX(4px);
}

/* --------------------------
   4. ファーストビュー（ヒーロー）
   -------------------------- */
.hero {
    position: relative;
    min-height: 65vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
    background-color: var(--color-beige);
}

/* 背景画像 */
.hero-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.hero-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* オーバーレイ（画像の上にかぶせる半透明レイヤー） */
.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg,
            rgba(250, 248, 245, 0.88) 0%,
            rgba(250, 248, 245, 0.78) 40%,
            rgba(250, 248, 245, 0.65) 100%);
    z-index: 2;
}

/* テキストコンテンツ */
.hero-content {
    position: relative;
    z-index: 3;
    padding: 60px 20px 50px;
    max-width: 700px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: 6px 20px;
    background-color: var(--color-accent);
    color: var(--color-white);
    font-size: 0.75rem;
    letter-spacing: 0.15em;
    border-radius: 20px;
    margin-bottom: 20px;
}

.hero-title {
    font-family: var(--font-serif);
    font-size: 2.2rem;
    font-weight: 500;
    color: var(--color-brown-dark);
    margin-bottom: 16px;
    letter-spacing: 0.08em;
    line-height: 1.5;
    /* 白い光彩で文字を浮き立たせる */
    text-shadow:
        0 0 15px rgba(255, 255, 255, 1),
        0 0 25px rgba(255, 255, 255, 0.8),
        2px 2px 0 rgba(255, 255, 255, 0.5);
}

.hero-subtitle {
    font-size: 0.95rem;
    color: var(--color-text);
    line-height: 1.9;
    letter-spacing: 0.03em;
    max-width: 600px;
    margin: 0 auto;
    text-shadow: 0 0 10px rgba(255, 255, 255, 1);
    font-weight: 500;
}

/* ヒーロー装飾パーツ */
.hero-deco {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin-top: 32px;
}

.hero-deco__item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.hero-deco__icon {
    width: 48px;
    height: 48px;
    background-color: var(--color-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-brown);
    box-shadow: 0 2px 12px rgba(92, 74, 58, 0.12);
}

.hero-deco__icon svg {
    width: 22px;
    height: 22px;
}

.hero-deco__text {
    font-size: 0.75rem;
    color: var(--color-brown-dark);
    font-weight: 500;
    letter-spacing: 0.03em;
    text-shadow: 0 0 8px rgba(255, 255, 255, 0.9);
}

/* --------------------------
   5. シリーズナビゲーション
   -------------------------- */
.series-nav {
    background-color: var(--color-white);
    padding: 40px 20px;
    border-bottom: 1px solid var(--color-beige-dark);
}

.series-nav__title {
    text-align: center;
    font-size: 0.8rem;
    color: var(--color-text-light);
    letter-spacing: 0.1em;
    margin-bottom: 24px;
    font-weight: 400;
}

.series-nav__list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    max-width: 600px;
    margin: 0 auto;
}

.series-nav__item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 20px;
    background-color: var(--color-cream);
    border: 1px solid var(--color-beige-dark);
    border-radius: 8px;
    transition: all 0.3s ease;
}

.series-nav__item:hover {
    background-color: var(--color-beige);
    border-color: var(--color-brown-light);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(92, 74, 58, 0.08);
    opacity: 1;
}

.series-nav__number {
    font-family: var(--font-serif);
    font-size: 0.7rem;
    color: var(--color-white);
    background-color: var(--color-accent);
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    letter-spacing: 0;
}

.series-nav__info {
    flex: 1;
    min-width: 0;
}

.series-nav__name {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-brown-dark);
    margin-bottom: 2px;
    line-height: 1.4;
}

.series-nav__desc {
    font-size: 0.8rem;
    color: var(--color-text-light);
    line-height: 1.5;
}

.series-nav__arrow {
    color: var(--color-brown);
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.series-nav__arrow svg {
    width: 16px;
    height: 16px;
}

.series-nav__item:hover .series-nav__arrow {
    transform: translateX(4px);
}

/* --------------------------
   追加リンク
   -------------------------- */
.series-nav__extras {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    max-width: 600px;
    margin: 24px auto 0;
}

.series-nav__extra-link {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 20px;
    background-color: var(--color-white);
    border: 1px solid var(--color-brown-light);
    color: var(--color-brown);
    border-radius: 4px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    text-align: center;
}

.series-nav__extra-link:hover {
    background-color: var(--color-brown-light);
    color: var(--color-white);
    opacity: 1;
}

.series-nav__extra-link svg {
    width: 16px;
    height: 16px;
    transition: transform 0.3s ease;
}

.series-nav__extra-link:hover svg {
    transform: translateX(4px);
}

.series-section {
    padding: var(--section-padding);
}

.series-section--a {
    background-color: var(--color-cream);
}

.series-section--b {
    background-color: var(--color-white);
}

.series-section--c {
    background-color: var(--color-cream);
}

/* シリーズヘッダー */
.series-header {
    text-align: center;
    margin-bottom: 40px;
}

.series-header__badge {
    display: inline-block;
    padding: 4px 16px;
    font-size: 0.7rem;
    letter-spacing: 0.15em;
    border-radius: 16px;
    margin-bottom: 12px;
    font-weight: 500;
}

.series-section--a .series-header__badge {
    background-color: var(--series-a-bg);
    color: var(--series-a-color);
}

.series-section--b .series-header__badge {
    background-color: var(--series-b-bg);
    color: var(--series-b-color);
}

.series-section--c .series-header__badge {
    background-color: var(--series-c-bg);
    color: var(--series-c-color);
}

.series-header__title {
    font-family: var(--font-serif);
    font-size: 1.6rem;
    font-weight: 500;
    color: var(--color-brown-dark);
    letter-spacing: 0.08em;
    margin-bottom: 6px;
}

.series-header__subtitle {
    font-size: 0.85rem;
    color: var(--color-text-light);
    letter-spacing: 0.05em;
}

/* シリーズ紹介コンテンツ */
.series-intro {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    margin-bottom: 48px;
}

.series-intro__image {
    border-radius: 12px;
    overflow: hidden;
    background-color: var(--color-beige);
    aspect-ratio: 16 / 10;
}

.series-intro__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.series-intro__body {
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.series-intro__catch {
    font-family: var(--font-serif);
    font-size: 1.2rem;
    color: var(--color-brown-dark);
    margin-bottom: 16px;
    line-height: 1.7;
    letter-spacing: 0.05em;
}

.series-intro__desc {
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.9;
    margin-bottom: 12px;
}

/* シリーズ特徴タグ */
.series-features {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 16px;
}

.series-features__tag {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 6px 14px;
    background-color: var(--color-white);
    border: 1px solid var(--color-beige-dark);
    border-radius: 20px;
    font-size: 0.78rem;
    color: var(--color-brown);
    font-weight: 500;
}

.series-features__tag svg {
    width: 14px;
    height: 14px;
}

/* シリーズ内の詳しくはこちらボタン */
.series-intro__cta {
    margin-top: 24px;
}

.series-intro__cta-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.9rem;
    color: var(--color-accent);
    font-weight: 500;
    border-bottom: 1px solid var(--color-accent);
    padding-bottom: 2px;
    transition: all 0.3s ease;
}

.series-intro__cta-link:hover {
    color: var(--color-brown-dark);
    border-color: var(--color-brown-dark);
    opacity: 1;
}

.series-intro__cta-link svg {
    width: 16px;
    height: 16px;
    transition: transform 0.3s ease;
}

.series-intro__cta-link:hover svg {
    transform: translateX(4px);
}

/* --------------------------
   7. 商品ラインナップグリッド
   -------------------------- */
.lineup {
    margin-top: 0;
}

.lineup__title {
    font-size: 0.85rem;
    color: var(--color-brown);
    text-align: center;
    margin-bottom: 20px;
    letter-spacing: 0.1em;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

.lineup__title::before,
.lineup__title::after {
    content: '';
    width: 40px;
    height: 1px;
    background-color: var(--color-brown-light);
}

.lineup__title span {
    display: block;
    font-size: 0.65rem;
    color: var(--color-text-light);
    letter-spacing: 0.15em;
    font-weight: 400;
    text-transform: uppercase;
}

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

/* 商品カード */
.lineup-card {
    background-color: var(--color-white);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--color-beige-dark);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.lineup-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(92, 74, 58, 0.1);
    opacity: 1;
}

.lineup-card__image {
    aspect-ratio: 1 / 1;
    overflow: hidden;
    background-color: var(--color-beige);
}

.lineup-card__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.lineup-card:hover .lineup-card__image img {
    transform: scale(1.05);
}

.lineup-card__body {
    padding: 12px;
}

.lineup-card__name {
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--color-brown-dark);
    line-height: 1.4;
    margin-bottom: 4px;
}

.lineup-card__price {
    font-size: 0.85rem;
    color: var(--color-accent);
    font-weight: 500;
}

.lineup-card__price-tax {
    font-size: 0.7rem;
    color: var(--color-text-light);
    font-weight: 400;
}

.lineup-card__color {
    font-size: 0.72rem;
    color: var(--color-text-light);
    margin-top: 4px;
    line-height: 1.4;
}

/* もっと見るリンク */
.lineup__more {
    text-align: center;
    margin-top: 24px;
}

.lineup__more-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 12px 28px;
    background-color: transparent;
    color: var(--color-brown);
    border: 1px solid var(--color-brown);
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.lineup__more-link:hover {
    background-color: var(--color-brown);
    color: var(--color-white);
    opacity: 1;
}

.lineup__more-link svg {
    width: 16px;
    height: 16px;
    transition: transform 0.3s ease;
}

.lineup__more-link:hover svg {
    transform: translateX(4px);
}

/* --------------------------
   8. その他の学習椅子セクション
   -------------------------- */
.others {
    padding: var(--section-padding);
    background-color: var(--color-beige);
}

.others__subtitle {
    text-align: center;
    font-size: 0.9rem;
    color: var(--color-text-light);
    margin-top: -28px;
    margin-bottom: 36px;
    line-height: 1.8;
}

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

/* その他の商品カード */
.others-card {
    background-color: var(--color-white);
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--color-beige-dark);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.others-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(92, 74, 58, 0.1);
    opacity: 1;
}

.others-card__image {
    aspect-ratio: 1 / 1;
    overflow: hidden;
    background-color: var(--color-beige);
}

.others-card__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.others-card:hover .others-card__image img {
    transform: scale(1.05);
}

.others-card__body {
    padding: 12px;
}

.others-card__name {
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--color-brown-dark);
    line-height: 1.4;
    margin-bottom: 4px;
}

.others-card__price {
    font-size: 0.85rem;
    color: var(--color-accent);
    font-weight: 500;
}

.others-card__price-tax {
    font-size: 0.7rem;
    color: var(--color-text-light);
    font-weight: 400;
}

.others-card__desc {
    font-size: 0.75rem;
    color: var(--color-text-light);
    margin-top: 4px;
    line-height: 1.5;
}

/* --------------------------
   9. フッター
   -------------------------- */

/* CTAフッター（フッター上の訴求エリア） */
.cta-footer {
    padding: 60px 20px;
    background: linear-gradient(135deg, var(--color-beige) 0%, var(--color-cream) 100%);
    text-align: center;
}

.cta-footer__title {
    font-family: var(--font-serif);
    font-size: 1.4rem;
    color: var(--color-brown-dark);
    margin-bottom: 16px;
    letter-spacing: 0.08em;
    line-height: 1.6;
}

.cta-footer__text {
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.9;
    margin-bottom: 28px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

/* --------------------------
   10. アニメーション
   -------------------------- */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* ページトップへ戻るボタン */
.study-chair-lp .back-to-top {
    position: fixed;
    bottom: 24px;
    right: 24px;
    width: 44px;
    height: 44px;
    background-color: var(--color-brown);
    color: var(--color-white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 16px rgba(92, 74, 58, 0.2);
    transition: background-color 0.3s ease, transform 0.2s ease;
    z-index: 100;
}

.study-chair-lp .back-to-top:hover {
    background-color: var(--color-brown-dark);
    transform: translateY(-2px);
}

.study-chair-lp .back-to-top svg {
    width: 20px;
    height: 20px;
}

/* --------------------------
   11. レスポンシブ対応
   タブレット (768px以上)
   -------------------------- */
@media screen and (min-width: 768px) {
    .hero {
        min-height: 70vh;
    }

    .hero-content {
        padding: 80px 20px 70px;
    }

    .hero-title {
        font-size: 2.6rem;
    }

    .hero-subtitle {
        font-size: 1.05rem;
    }

    .hero-deco {
        gap: 60px;
        margin-top: 40px;
    }

    .hero-deco__icon {
        width: 56px;
        height: 56px;
    }

    .hero-deco__icon svg {
        width: 26px;
        height: 26px;
    }

    .hero-deco__text {
        font-size: 0.8rem;
    }

    /* シリーズナビゲーション: 横並び */
    .series-nav {
        padding: 48px 20px;
    }

    .series-nav__list {
        flex-direction: row;
        max-width: 900px;
    }

    .series-nav__item {
        flex: 1;
        flex-direction: column;
        text-align: center;
        padding: 24px 16px;
        gap: 12px;
    }

    .series-nav__arrow {
        display: none;
    }

    /* 追加リンク: 横並び */
    .series-nav__extras {
        grid-template-columns: 1fr 1fr;
        max-width: 900px;
        margin-top: 32px;
        gap: 16px;
    }

    /* シリーズ紹介: 2カラムレイアウト */
    .series-intro {
        grid-template-columns: 1fr 1fr;
        gap: 40px;
        align-items: center;
    }

    /* 偶数セクションは画像と文章を反転 */
    .series-section--b .series-intro {
        direction: rtl;
    }

    .series-section--b .series-intro>* {
        direction: ltr;
    }

    /* 商品グリッド: 3列 */
    .lineup__grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 16px;
    }

    .lineup-card__body {
        padding: 16px;
    }

    .lineup-card__name {
        font-size: 0.88rem;
    }

    /* その他グリッド: 3列 */
    .others__grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 16px;
    }

    .others-card__body {
        padding: 16px;
    }

    /* セクションタイトル */
    .section-title {
        font-size: 1.8rem;
        margin-bottom: 48px;
    }

    .series-header__title {
        font-size: 1.8rem;
    }

    .series-intro__catch {
        font-size: 1.3rem;
    }
}

/* --------------------------
   PC (1024px以上)
   -------------------------- */
@media screen and (min-width: 1024px) {
    .hero {
        min-height: 75vh;
    }

    .hero-content {
        padding: 100px 20px 80px;
    }

    .hero-title {
        font-size: 2.8rem;
    }

    /* 商品グリッド: 4列 */
    .lineup__grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 20px;
    }

    /* その他グリッド: 4列 */
    .others__grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 20px;
    }

    /* シリーズ紹介の余白 */
    .series-intro {
        gap: 60px;
    }

    .series-section {
        padding: 100px 20px;
    }
}

/* --------------------------
   小画面 (480px以下)
   -------------------------- */
@media screen and (max-width: 480px) {
    .hero {
        min-height: 55vh;
    }

    .hero-content {
        padding: 48px 16px 40px;
    }

    .hero-title {
        font-size: 1.7rem;
    }

    .hero-badge {
        font-size: 0.68rem;
        padding: 5px 16px;
    }

    .hero-deco {
        gap: 24px;
    }

    .hero-deco__icon {
        width: 40px;
        height: 40px;
    }

    .hero-deco__icon svg {
        width: 18px;
        height: 18px;
    }

    .hero-deco__text {
        font-size: 0.68rem;
    }

    .section-title {
        font-size: 1.4rem;
    }

    .series-header__title {
        font-size: 1.3rem;
    }

    .series-intro__catch {
        font-size: 1.1rem;
    }

    .series-section {
        padding: var(--section-padding-mobile);
    }

    .others {
        padding: var(--section-padding-mobile);
    }

    .cta-footer {
        padding: 48px 16px;
    }

    .cta-footer__title {
        font-size: 1.2rem;
    }

    .series-nav__item {
        padding: 14px 16px;
    }

    .series-nav__name {
        font-size: 0.88rem;
    }
}