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

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: #1A1A1A;
    background-color: #FFFFFF;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ヒーローセクション */
.hero {
    background: linear-gradient(rgba(0,0,0,0.1), rgba(0,0,0,0)), url('../images/main-visual.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    position: relative;
    animation: subtleBackgroundMove 60s ease-in-out infinite;
    overflow: hidden;
}

/* 背景の安定した動き（サイズ変更なし） */
@keyframes subtleBackgroundMove {
    0% {
        background-position: center center;
    }
    25% {
        background-position: 50.2% 49.8%;
    }
    50% {
        background-position: 49.8% 50.2%;
    }
    75% {
        background-position: 50.1% 49.9%;
    }
    100% {
        background-position: center center;
    }
}

/* より繊細な光の変化効果 */
.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        45deg,
        rgba(255, 255, 255, 0.02) 0%,
        rgba(255, 255, 255, 0.05) 25%,
        rgba(255, 255, 255, 0.02) 50%,
        rgba(255, 255, 255, 0.08) 75%,
        rgba(255, 255, 255, 0.02) 100%
    );
    animation: subtleLightShift 15s ease-in-out infinite;
    pointer-events: none;
}

@keyframes subtleLightShift {
    0%, 100% {
        opacity: 0.3;
        transform: translateX(0) translateY(0);
    }
    25% {
        opacity: 0.5;
        transform: translateX(8px) translateY(-2px);
    }
    50% {
        opacity: 0.4;
        transform: translateX(-6px) translateY(3px);
    }
    75% {
        opacity: 0.6;
        transform: translateX(4px) translateY(1px);
    }
}

/* 微細なパーティクル効果 */
.hero::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(255,255,255,0.1), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.08), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(255,255,255,0.12), transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255,255,255,0.06), transparent),
        radial-gradient(2px 2px at 160px 30px, rgba(255,255,255,0.1), transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: subtleParticleFloat 25s linear infinite;
    pointer-events: none;
    opacity: 0.4;
}

@keyframes subtleParticleFloat {
    0% {
        transform: translateY(0px) translateX(0px);
    }
    50% {
        transform: translateY(-3px) translateX(2px);
    }
    100% {
        transform: translateY(0px) translateX(0px);
    }
}

.hero-content {
    padding: 100px 0px;
    border-radius: 20px;
    max-width: 800px;
    margin: 0 20px;
    top: 0;
    position: absolute;
}

/* ファーストビュー内ハンバーガーメニュー */
.hero-hamburger {
    display: none;
    position: absolute;
    top: 20px;
    right: 20px;
    flex-direction: column;
    cursor: pointer;
    padding: 10px;
    z-index: 101;
}

.hero-hamburger span {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.hero-hamburger.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

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

.hero-hamburger.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

.hero h1 {
    font-size: 3rem;
    font-weight: 300;
    line-height: 1.1;
    letter-spacing: -1.28px;
    margin-bottom: 30px;
    color: #1A1A1A;
}

.hero p {
    font-size: 20px;
    font-weight: 300;
    line-height: 1.5;
    color: #666666;
}

/* ヒーローテキストアニメーション */
.hero-title, .hero-subtitle {
    opacity: 0;
    transform: translateY(30px);
    transition: all 1.2s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
}

.hero-title.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.hero-subtitle.animate-in {
    opacity: 1;
    transform: translateY(0);
}

/* 上品なグラデーション効果 */
.hero-title::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    transform: translateX(-100%);
    transition: transform 1.5s ease-in-out;
}

.hero-title.animate-in::after {
    transform: translateX(100%);
}

/* より洗練された文字アニメーション */
.hero-title {
    background: linear-gradient(45deg, #1A1A1A, #333333);
    background-size: 200% 200%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 3s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

/* セクション共通 */
.section {
    padding: 100px 0;
}

.section-title {
    font-size: 40px;
/*    font-weight: 300; */
    font-weight: bold;
    text-align: center;
    margin-bottom: 20px;
    color: #1A1A1A;
}

.section-subtitle {
    font-size: 18px;
    font-weight: 400;
    line-height: 1.6;
    color: #666666;
    text-align: center;
    margin-bottom: 60px;
}

/* 主要機能セクション */
.features-section {
    background-color: #FFFFFF;
}

.feature-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    margin-bottom: 80px;
}

.feature-item {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.feature-content {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.feature-number {
    font-size: 24px;
    font-weight: bold;
    width: 180px;
    border-bottom: solid;
    color: #666666;
    letter-spacing: 2px;
}

.feature-title {
    font-size: 28px;
    font-weight: bold;
    line-height: 1.3;
    color: #1A1A1A;
}

.feature-description {
    font-size: 16px;
    font-weight: 400;
    line-height: 1.6;
    color: #666666;
}

.feature-highlight {
    background: #F8F8F8;
    padding: 20px;
    border-radius: 12px;
    border-left: 4px solid #333333;
}

.highlight-title {
    font-size: 14px;
    font-weight: 500;
    color: #333333;
    margin-bottom: 8px;
}

.highlight-text {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.5;
    color: #666666;
}

.feature-image {
    width: 100%;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
}

.feature-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* Problem: 問題提起セクション */
.problem-section {
    background-color: #FAFAFA;
}

.problem-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    margin-top: 60px;
}

.problem-card {
    background: white;
    border-radius: 16px;
    padding: 30px 20px;
    text-align: center;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    border-left: 4px solid #ff6b6b;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.problem-card:hover {
    transform: translateY(-5px);
}

.problem-icon {
    width: 120px;
    height: 120px;
    margin: 0 auto 20px auto;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0px 5px 15px rgba(0, 0, 0, 0.1);
}

.problem-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.problem-title {
    font-size: 18px;
    font-weight: 500;
    color: #1A1A1A;
    margin-bottom: 15px;
    line-height: 1.3;
}

.problem-description {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.6;
    color: #666666;
    flex-grow: 1;
}

/* Amplify: 問題の拡大セクション */
.amplify-section {
    background-color: #1A1A1A;
    color: white;
    padding: 60px 0;
}

.amplify-section .section-title {
    color: white;
}

.amplify-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-bottom: 30px;
}

.amplify-text h3 {
    font-size: 24px;
    font-weight: 500;
    margin-bottom: 20px;
    color: white;
}

.amplify-text ul {
    list-style: none;
    padding: 0;
}

.amplify-text li {
    padding: 10px 0;
    border-bottom: 1px solid #333;
    position: relative;
    padding-left: 20px;
}

.amplify-text li:before {
    content: "⚠️";
    position: absolute;
    left: 0;
}

.amplify-cta {
    text-align: center;
    background: rgba(255, 107, 107, 0.1);
    padding: 20px;
    border-radius: 12px;
    border: 2px solid #ff6b6b;
}

.amplify-cta p {
    font-size: 16px;
    font-weight: 500;
    color: #ff6b6b;
    margin: 0;
}

/* Solution: 解決策セクション */
.solution-section {
    background-color: #FFFFFF;
}

.solution-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    margin-top: 60px;
}

.solution-item {
    background: white;
    border-radius: 16px;
    padding: 30px 20px;
    text-align: center;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    border-left: 4px solid #4ecdc4;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.solution-item:hover {
    transform: translateY(-5px);
}

.solution-icon {
    width: 120px;
    height: 120px;
    margin: 0 auto 20px auto;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0px 5px 15px rgba(0, 0, 0, 0.1);
}

.solution-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.solution-item h3 {
    font-size: 18px;
    font-weight: 500;
    color: #1A1A1A;
    margin-bottom: 15px;
    line-height: 1.3;
}

.solution-item p {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.6;
    color: #666666;
    flex-grow: 1;
}
/* 品質保証セクション */
.quality-section {
    background-color: #FAFAFA;
}

.quality-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    margin-top: 60px;
}

.quality-card {
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.2);
    position: relative;
    height: 300px;
    background-size: cover;
    background-position: center;
}

.quality-card.japan {
    background-image: url('../images/japanese-design.jpg');
}

.quality-card.warranty {
    background-image: url('../images/quality-warranty.jpg');
}

.quality-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(128, 128, 128, 0.65);
    z-index: 1;
}

.quality-content {
    padding: 40px 30px;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    position: relative;
    z-index: 2;
}

.quality-title {
    font-size: 28.8px;
/*    font-weight: 300; */
    font-weight: bold;
    color: #FFCC00;
    margin-bottom: 20px;
}

.quality-description {
    background: rgba(255, 255, 255, 0.2);
    padding: 4px 8px;
    border-radius: 4px;
}

.quality-text {
    font-size: 15px;
    font-weight: 400;
    line-height: 1.5;
    color: rgba(255, 255, 255, 0.9);
}

/* Transform: 変革の約束セクション */
.transform-section {
    background-color: #FAFAFA;
}

.transform-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.transform-current, .transform-expected {
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
}

.transform-current h3 {
    color: #ff6b6b;
    font-size: 24px;
    margin-bottom: 30px;
    text-align: center;
}

.transform-expected h3 {
    color: #4ecdc4;
    font-size: 24px;
    margin-bottom: 30px;
    text-align: center;
}

.transform-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.transform-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px;
    border-radius: 8px;
}

.transform-item.negative {
    background: rgba(255, 107, 107, 0.1);
    border-left: 4px solid #ff6b6b;
}

.transform-item.positive {
    background: rgba(78, 205, 196, 0.1);
    border-left: 4px solid #4ecdc4;
}

.transform-icon {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.transform-icon i {
    font-size: 16px;
    font-weight: 600;
}

.transform-item.negative .transform-icon i {
    color: #ff6b6b;
}

.transform-item.positive .transform-icon i {
    color: #4ecdc4;
}

.transform-item p {
    margin: 0;
    font-weight: 500;
}

.transform-note {
    background: rgba(78, 205, 196, 0.1);
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    border-left: 4px solid #4ecdc4;
}

.transform-note p {
    font-size: 14px;
    color: #666666;
    margin: 0;
    line-height: 1.5;
}

/* Offer: 特別オファーセクション */
.offer-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.offer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 60px;
    align-items: center;
}

.offer-price {
    text-align: center;
    margin-bottom: 40px;
}

.price-original {
    font-size: 18px;
    text-decoration: line-through;
    opacity: 0.7;
    margin-bottom: 10px;
}

.price-special {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 10px;
}

.price-save {
    font-size: 20px;
    color: #ffd700;
    font-weight: 600;
}

.offer-benefits h3 {
    font-size: 24px;
    margin-bottom: 20px;
}

.offer-benefits ul {
    list-style: none;
    padding: 0;
}

.offer-benefits li {
    padding: 10px 0;
    font-size: 16px;
}

.offer-urgency {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 30px;
    text-align: center;
}

.urgency-timer h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: #ffd700;
}

.stock-info {
    background: rgba(255, 107, 107, 0.2);
    border-radius: 8px;
    padding: 15px;
    margin-top: 20px;
}

.stock-count {
    font-size: 18px;
    font-weight: 600;
    color: #ff6b6b;
}

/* Response: 行動喚起セクション */
.response-section {
    background-color: #1A1A1A;
    color: white;
}

.response-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.response-urgency h3 {
    font-size: 24px;
    margin-bottom: 30px;
    color: #ff6b6b;
}

.urgency-reasons {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.reason-item {
    display: flex;
    align-items: center;
    gap: 20px;
    background: rgba(255, 255, 255, 0.05);
    padding: 20px;
    border-radius: 12px;
    border-left: 4px solid #ff6b6b;
}

.reason-number {
    background: #ff6b6b;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 18px;
}

.reason-item p {
    margin: 0;
    font-size: 16px;
    line-height: 1.5;
}

.response-cta {
    text-align: center;
}

.response-cta h3 {
    font-size: 24px;
    margin-bottom: 20px;
    color: #4ecdc4;
}

.response-cta p {
    font-size: 16px;
    margin-bottom: 30px;
    opacity: 0.9;
}

.cta-buttons {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.cta-button {
    display: inline-block;
    padding: 15px 30px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
    text-align: center;
}

.cta-button.primary {
    background: #4ecdc4;
    color: white;
}

.cta-button.primary:hover {
    background: #45b7b8;
    transform: translateY(-2px);
}

.cta-button.secondary {
    background: transparent;
    color: #4ecdc4;
    border: 2px solid #4ecdc4;
}

.cta-button.secondary:hover {
    background: #4ecdc4;
    color: white;
}

/* メリットセクション */
.benefits-section {
    background-color: #FAFAFA;
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    margin-top: 60px;
}

.benefit-card {
    background: white;
    border-radius: 16px;
    padding: 40px;
    text-align: center;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.benefit-card:hover {
    transform: translateY(-5px);
}

.benefit-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 20px auto;
    display: flex;
    align-items: center;
    justify-content: center;
}

.benefit-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.benefit-title {
    font-size: 20px;
    font-weight: 500;
    color: #1A1A1A;
    margin-bottom: 15px;
}

.benefit-description {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.6;
    color: #666666;
}

/* カラーバリエーションセクション */
.colors-section {
    background-color: #FAFAFA;
}

.colors-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
    margin-top: 60px;
}

.color-item {
    text-align: center;
}

.color-image {
    width: 400px;
    height: 400px;
    border-radius: 20px;
    overflow: hidden;
    margin: 0 auto 40px;
}

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

.color-name {
    font-size: 20px;
    font-weight: 500;
    color: #1A1A1A;
}

/* 製品仕様セクション */
.specs-section {
    background-color: #FFFFFF;
}

.specs-tabs {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 60px;
}

.spec-tab {
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.spec-tab:hover {
    transform: translateY(-5px);
}

.spec-tab img {
    width: 250px;
    height: 250px;
    border-radius: 12px;
    margin-bottom: 15px;
    box-shadow: 0px 5px 15px rgba(0, 0, 0, 0.1);
    object-fit: cover;
}

.spec-tab-label {
    font-size: 16px;
    font-weight: 500;
    color: #666666;
}

.specs-table {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
}

.spec-row {
    display: flex;
    border-bottom: 1px solid #E0E0E0;
}

.spec-row:last-child {
    border-bottom: none;
}

.spec-label {
    width: 200px;
    padding: 20px;
    align-items: center;
    display: flex;
    background: #F8F8F8;
    font-size: 16px;
    font-weight: 500;
    color: #1A1A1A;
}

.spec-value {
    flex: 1;
    padding: 20px;
    font-size: 16px;
    font-weight: 400;
    color: #666666;
}
.spec-image {
    max-width: 400px;
    margin-bottom: 20px;
    margin-top: 20px;
    margin-left: auto;
    margin-right: auto;
    border-radius: 1px;
    overflow: hidden;
    box-shadow: 0px 20px 40px rgba(0, 0, 0, 0.3);
}

.spec-image img {
    width: 100%;
    height: auto;
    display: block;
}
/* フッターセクション */
.footer-content {
    text-align: center;
}
.footer-section {
    background-color: #1A1A1A;
    color: white;
}
.footer-description {
    font-size: 13px;
    padding-top: 10px;
    padding-bottom: 10px;
    opacity: 0.8;
}
/* coming Soonセクション */
.coming-content {
    text-align: center;
}

.coming-image {
    max-width: 800px;
    margin: 0 auto;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0px 20px 40px rgba(0, 0, 0, 0.3);
}
.coming-image img {
    width: 100%;
    height: auto;
    display: block;
}
/* オンラインショップセクション */
.shop-section {
    background-color: #FAFAFA;
}

.shop-content {
    text-align: center;
    margin-bottom: 60px;
}

.shop-description {
    font-size: 18px;
    font-weight: 400;
    line-height: 1.6;
    margin-bottom: 30px;
    color: #666666;
}

.shop-images {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.shop-image {
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0px 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.shop-image:hover {
    transform: translateY(-5px);
}

.shop-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* ナビゲーション */
.nav {
    background: white;
    border-bottom: 1px solid #E0E0E0;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all 0.3s ease;
}

.nav.scrolled {
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-container {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 5px 0;
    position: relative;
}

.nav-links {
    display: flex;
    gap: 40px;
}

/* ハンバーガーメニュー */
.hamburger-menu {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 10px;
    z-index: 101;
}

.hamburger-menu span {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.hamburger-menu.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

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

.hamburger-menu.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

.nav-link {
    color: #666666;
    padding: 9px 20px;
    border-radius: 20px;
    text-decoration: none;
    font-size: 15.2px;
    font-weight: 400;
    transition: all 0.3s ease;
}

.nav-link:hover {
    background: #333333;
    color: white;
}

/* 固定購入ボタン */
.fixed-purchase-button {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: white;
    padding: 15px 20px;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
    z-index: 99;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

.fixed-purchase-button.show {
    transform: translateY(0);
}

.purchase-btn {
    display: block;
    background: #333;
    color: white;
    text-align: center;
    padding: 15px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    font-size: 16px;
    transition: background 0.3s ease;
}

.purchase-btn:hover {
    background: #555;
}

/* レスポンシブデザイン */
/* 大画面でのアニメーション最適化 */
@media (min-width: 1201px) and (max-width: 1800px) {
    .hero {
        animation: subtleBackgroundMove 120s ease-in-out infinite; /* より遅いアニメーション */
    }
    
    .hero::before {
        animation: subtleLightShift 30s ease-in-out infinite; /* より遅い光の変化 */
    }
    
    .hero::after {
        animation: subtleParticleFloat 40s ease-in-out infinite; /* より遅いパーティクル */
    }
}

@media (max-width: 1200px) and (min-width: 901px) {
    .hero {
        background: linear-gradient(rgba(0,0,0,0.1), rgba(0,0,0,0.1)), url('../images/main-visual.jpg');
        background-size: cover;
        background-position: center;
        animation: none; /* TABではアニメーションを無効化 */
    }
    
    .hero::before {
        animation: none; /* 光の変化効果を無効化 */
    }
    
    .hero::after {
        animation: none; /* パーティクル効果を無効化 */
    }
    
    .container {
        padding: 0 30px;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
        gap: 60px;
        margin-bottom: 60px;
    }
    
    .feature-item {
        flex-direction: column;
        text-align: center;
        gap: 30px;
    }
    
    .feature-image {
        width: 100%;
        max-width: 500px;
        order: 1;
    }
    
    .feature-content {
        order: 2;
    }
    
    .feature-number {
        order: 1;
    }
    
    .feature-title {
        order: 2;
    }
    
    .feature-description {
        order: 3;
    }
    
    .feature-highlight {
        order: 4;
    }
    
    .problem-grid,
    .solution-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    .benefits-grid {
        grid-template-columns: 1fr;
    }
    
    .specs-tabs {
        gap: 15px;
    }
    
    .spec-tab img {
        width: 180px;
        height: 180px;
    }
    
    .amplify-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .transform-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .offer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .response-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .colors-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .color-image {
        width: 280px;
        height: 280px;
    }
    
    .shop-images {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 900px) {
    .problem-grid,
    .solution-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }
    
    .problem-card,
    .solution-item {
        padding: 20px 15px;
    }
    
    .problem-icon,
    .solution-icon {
        width: 90px;
        height: 90px;
    }
}

@media (max-width: 768px) {
    .hero {
        background: linear-gradient(rgba(0,0,0,0.1), rgba(0,0,0,0.1)), url('../images/main-visual.jpg');
        background-size: cover;
        background-position: center;
        animation: none; /* スマホではアニメーションを無効化 */
    }
    
    .hero::before {
        animation: none; /* 光の変化効果を無効化 */
    }
    
    .hero::after {
        animation: none; /* パーティクル効果を無効化 */
    }
    
    .hero h1 {
        font-size: 36px;
        line-height: 1.2;
    }
    
    .hero p {
        font-size: 16px;
        line-height: 1.5;
    }
    
    .container {
        padding: 0 20px;
    }
    
    .section-title {
        font-size: 28px;
        margin-bottom: 40px;
    }
    
    .feature-title {
        font-size: 24px;
    }
    
    .feature-grid {
        gap: 60px;
        margin-bottom: 50px;
        grid-template-columns: 1fr;
    }
    
    .feature-item {
        gap: 25px;
    }
    
    /* ファーストビュー内ハンバーガーメニュー表示 */
    .hero-hamburger {
        display: flex;
    }
    
    /* 固定購入ボタンを表示 */
    .fixed-purchase-button {
        display: block;
    }
    
    /* 通常のナビゲーションを非表示 */
    .nav {
        display: none;
    }
    
    /* メニューが開いている時はナビゲーションを表示 */
    .nav.menu-open {
        display: block;
    }
    
    /* ナビゲーションを追従するように変更 */
    .nav {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        z-index: 100;
    }
    
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 250px;
        height: 100vh;
        background: white;
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        padding-top: 80px;
        gap: 30px;
        box-shadow: -2px 0 10px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        z-index: 100;
    }
    
    .nav-links.active {
        right: 0;
    }
    
    .nav-link {
        font-size: 18px;
        padding: 15px 20px;
        width: 80%;
        text-align: center;
        border-radius: 10px;
    }
    
    .spec-row {
        flex-direction: column;
    }
    
    .spec-label {
        width: 100%;
    }
    
    .problem-grid,
    .solution-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .problem-card,
    .solution-item {
        padding: 25px 15px;
    }
    
    .problem-icon,
    .solution-icon {
        width: 100px;
        height: 100px;
    }
    
    .benefits-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .amplify-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .specs-tabs {
        flex-direction: column;
        gap: 20px;
        align-items: center;
    }
    
    .spec-tab {
        width: 100%;
        max-width: 300px;
    }
    
    .spec-tab img {
        width: 100%;
        height: 200px;
    }
    
    .transform-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .offer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .response-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .price-special {
        font-size: 36px;
    }
    
    .cta-buttons {
        flex-direction: column;
        gap: 10px;
    }
    .shop-images {
        grid-template-columns: 1fr;
    }
    .colors-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

@media (max-width: 480px) {
    .hero {
        animation: none; /* アニメーションを無効化 */
    }
    
    .hero::before {
        animation: none; /* 光の変化効果を無効化 */
    }
    
    .hero::after {
        animation: none; /* パーティクル効果を無効化 */
    }
    
    .container {
        padding: 0 15px;
    }
    
    .hero-content {
        padding: 100px 0px;
    }
    
    .hero h1 {
        font-size: 28px;
        line-height: 1.2;
    }
    
    .hero p {
        font-size: 14px;
        line-height: 1.4;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .feature-grid {
        gap: 50px;
        margin-bottom: 40px;
        grid-template-columns: 1fr;
    }
    
    .feature-item {
        gap: 20px;
    }
    
    .problem-card,
    .solution-item {
        padding: 20px 10px;
    }
    
    .problem-icon,
    .solution-icon {
        width: 80px;
        height: 80px;
    }
    
    .problem-title,
    .solution-item h3 {
        font-size: 16px;
    }
    
    .problem-description,
    .solution-item p {
        font-size: 13px;
    }
    .color-image {
        width: 100%;
        height: 350px;
    }   
    .spec-tab img {
        width: 100%;
        height: 150px;
    }
    
    .spec-tab-label {
        font-size: 14px;
    }
    
    .feature-title {
        font-size: 20px;
    }
    
    .feature-description {
        font-size: 16px;
    }
    
    .nav-links {
        flex-direction: column;
        align-items: center;
    }
    .spec-image {
    margin-left: 20px;
    margin-right: 20px;
    }
    .quality-grid {
        grid-template-columns: 1fr;
    }
}