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

html {
    overflow-x: hidden;
    width: 100%;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
    width: 100%;
}


/* Header */

header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px 50px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
}

.logo img {
    height: 60px;
    width: auto;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 40px;
}

nav a {
    color: #333;
    text-decoration: none;
    font-weight: 500;
    font-size: 16px;
    transition: color 0.3s;
    position: relative;
}

nav a:after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: #0099dc;
    transition: width 0.3s;
}

nav a:hover:after {
    width: 100%;
}

nav a:hover {
    color: #0099dc;
}


/* Mobile Menu Toggle (Hamburger) */

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
    z-index: 1001;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: #333;
    transition: all 0.3s ease;
    border-radius: 2px;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

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

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}


/* Mobile Navigation */

.mobile-nav {
    display: none;
    position: fixed;
    top: 100px;
    left: 0;
    width: 100%;
    background: white;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    z-index: 999;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.mobile-nav.active {
    max-height: 400px;
}

.mobile-nav ul {
    list-style: none;
    padding: 20px 0;
    display: block;
}

.mobile-nav li {
    border-bottom: 1px solid #f0f0f0;
}

.mobile-nav a {
    display: block;
    padding: 15px 30px;
    color: #333;
    text-decoration: none;
    font-weight: 500;
    transition: background 0.3s, color 0.3s;
}

.mobile-nav a:hover {
    background: #f8f9fa;
    color: #0099dc;
}

.mobile-nav a:after {
    display: none;
}


/* Breadcrumb */

.breadcrumb {
    margin-top: 100px;
    padding: 20px 50px;
    background: #f8f9fa;
}

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

.breadcrumb a {
    color: #666;
    text-decoration: none;
    font-size: 14px;
}

.breadcrumb a:hover {
    color: #0099dc;
}

.breadcrumb span {
    color: #333;
    margin: 0 10px;
}


/* Product Hero */

.product-hero {
    padding: 80px 50px;
    background: white;
}

.product-hero-container {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.product-image-main {
    text-align: center;
}

.product-image-main img {
    max-width: 100%;
    height: auto;
    max-height: 600px;
    object-fit: contain;
}

.product-info-main h1 {
    font-size: 42px;
    font-weight: 300;
    margin-bottom: 15px;
    color: #333;
}

.product-code {
    font-size: 18px;
    color: #0099dc;
    margin-bottom: 30px;
    font-weight: 500;
}

.product-description {
    font-size: 18px;
    color: #666;
    line-height: 1.8;
    margin-bottom: 40px;
}

.product-features-list {
    list-style: none;
    margin-bottom: 40px;
}

.product-features-list li {
    padding: 12px 0;
    border-bottom: 1px solid #e0e0e0;
    font-size: 16px;
    color: #555;
}

.product-features-list li:last-child {
    border-bottom: none;
}

.product-features-list li strong {
    color: #333;
    margin-right: 10px;
}

.cta-buttons {
    display: flex;
    gap: 20px;
}

.btn-primary {
    padding: 15px 40px;
    background: #0099dc;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 600;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: #0077b3;
}

.btn-secondary {
    padding: 15px 40px;
    background: white;
    color: #0099dc;
    text-decoration: none;
    border: 2px solid #0099dc;
    border-radius: 5px;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-secondary:hover {
    background: #0099dc;
    color: white;
}


/* Hero Carousel */

.hero-carousel {
    position: relative;
    width: 100%;
    height: 600px;
    /* 높이 지정 */
    overflow: hidden;
    /* 넘치는 부분 숨김 */
    display: flex;
    align-items: center;
    justify-content: center;
    padding-bottom: 50px;
    /* dots를 위한 공간 확보 */
}

.hero-slide {
    display: none;
    animation: heroFadeIn 0.8s;
    width: 100%;
    height: 100%;
}

.hero-slide.active {
    display: flex;
    /* 중앙 정렬을 위해 flex 사용 */
    align-items: center;
    justify-content: center;
}

.hero-slide img {
    max-width: 100%;
    max-height: 550px;
    /* 600px에서 550px로 줄임 (dots 공간 확보) */
    height: auto;
    object-fit: contain;
}

@keyframes heroFadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.hero-dots {
    text-align: center;
    position: absolute;
    bottom: 20px;
    width: 100%;
    z-index: 10;
    /* dots가 이미지 위에 표시되도록 */
}

.hero-dot {
    height: 12px;
    width: 12px;
    margin: 0 5px;
    background-color: #bbb;
    border-radius: 50%;
    display: inline-block;
    cursor: pointer;
    transition: background-color 0.3s;
}

.hero-dot.active,
.hero-dot:hover {
    background-color: #0099dc;
}


/* Product Definition Section */

.product-definition {
    position: relative;
    width: 100%;
    height: 500px;
    overflow: hidden;
}

.definition-container {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.definition-bg {
    position: absolute;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

.definition-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.3);
}

.definition-title {
    position: relative;
    z-index: 2;
    color: white;
    font-size: 42px;
    font-weight: 600;
    text-align: center;
    padding: 0 50px;
    max-width: 1000px;
}


/* Features Section */

.features-section {
    padding: 0;
    background: white;
}

.features-container {
    max-width: 100%;
    margin: 0 auto;
}

.section-title {
    text-align: center;
    font-size: 42px;
    font-weight: 300;
    padding: 80px 50px 60px;
    color: #333;
}

.feature-row {
    position: relative;
    height: 600px;
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    border-bottom: 3px solid white;
}

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

.feature-row.reverse {
    justify-content: flex-end;
}

.feature-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to right, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.1));
}

.feature-row.reverse .feature-overlay {
    background: linear-gradient(to left, rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.1));
}

.feature-text {
    position: relative;
    z-index: 2;
    max-width: 600px;
    padding: 50px;
    color: white;
    margin: 60px;
}

.feature-row.reverse .feature-text {
    text-align: right;
}

.feature-text h3 {
    font-size: 38px;
    font-weight: 600;
    margin-bottom: 20px;
    color: white;
}

.feature-text p {
    font-size: 18px;
    line-height: 1.8;
    color: white;
}


/* RO Filter Section */

.rofilter-section {
    background: #f8f9fa;
    padding: 80px 50px;
    position: relative;
}

.rofilter-container {
    max-width: 1400px;
    margin: 0 auto;
    position: relative;
}


/* Carousel Navigation */

.carousel-nav {
    text-align: center;
    margin-bottom: 40px;
}

.carousel-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    border: 2px solid #0099dc;
    background: transparent;
    margin: 0 8px;
    cursor: pointer;
    transition: all 0.3s;
    padding: 0;
}

.carousel-dot.active {
    background: #0099dc;
    width: 14px;
    height: 14px;
}

.carousel-dot:hover {
    background: #0099dc;
}


/* Slides */

.rofilter-slide {
    display: none;
    animation: fadeIn 0.5s;
}

.rofilter-slide.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.rofilter-main-title {
    font-size: 36px;
    font-weight: 600;
    text-align: center;
    color: #333;
    margin-bottom: 60px;
    line-height: 1.4;
}

.rofilter-content {
    background: white;
    padding: 60px;
    border-radius: 10px;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
    min-height: 600px;
}

.rofilter-subtitle {
    font-size: 32px;
    font-weight: 600;
    color: #0099dc;
    text-align: center;
    margin-bottom: 50px;
}

.rofilter-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-bottom: 50px;
}

.rofilter-feature {
    text-align: center;
}

.rofilter-feature img {
    max-width: 100%;
    height: auto;
    max-height: 300px;
    margin-bottom: 30px;
}

.rofilter-feature h4 {
    font-size: 22px;
    font-weight: 600;
    color: #0099dc;
    margin-bottom: 15px;
}

.rofilter-feature p {
    font-size: 16px;
    color: #555;
    line-height: 1.6;
}

.rofilter-feature sup {
    color: #0099dc;
    font-weight: 600;
}

.rofilter-references {
    border-top: 1px solid #e0e0e0;
    padding-top: 30px;
}

.rofilter-references p {
    font-size: 13px;
    color: #777;
    line-height: 1.6;
    margin-bottom: 15px;
}

.rofilter-references sup {
    color: #0099dc;
    font-weight: 600;
    margin-right: 5px;
}


/* Substances Section */

.rofilter-diagram {
    text-align: center;
    margin-bottom: 50px;
}

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

.substances-title {
    font-size: 32px;
    font-weight: 600;
    text-align: center;
    color: #333;
    margin-bottom: 40px;
}

.substances-list {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin-bottom: 50px;
}

.substance-group {
    flex: 1;
    padding: 35px 25px;
    background: #fff;
    border: 2px solid #0099dc;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 153, 220, 0.1);
    min-height: 150px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.substance-group p {
    font-size: 15px;
    color: #333;
    line-height: 2;
    text-align: left;
}

.substance-group sup {
    color: #0099dc;
    font-weight: 600;
}

.plus-sign {
    font-size: 48px;
    color: #0099dc;
    font-weight: 700;
    flex-shrink: 0;
    padding: 0 10px;
}


/* Specifications Section */

.specs-section {
    padding: 80px 50px;
    background: #f8f9fa;
}

.specs-container {
    max-width: 1200px;
    margin: 0 auto;
}

.specs-table {
    width: 100%;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
}

.specs-table tr {
    border-bottom: 1px solid #e0e0e0;
}

.specs-table tr:last-child {
    border-bottom: none;
}

.specs-table td {
    padding: 20px 30px;
    font-size: 16px;
}

.specs-table td:first-child {
    font-weight: 600;
    color: #333;
    width: 35%;
    background: #f8f9fa;
}

.specs-table td:last-child {
    color: #666;
}


/* Footer */

footer {
    background: #2c3e50;
    color: white;
    padding: 60px 50px 30px;
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-about h3 {
    font-size: 24px;
    margin-bottom: 20px;
    color: #0099dc;
}

.footer-about p {
    color: #bdc3c7;
    line-height: 1.8;
}

.footer-links h4 {
    margin-bottom: 20px;
    font-size: 18px;
}

.footer-links ul {
    list-style: none;
}

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    display: block;
    margin-bottom: 10px;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #0099dc;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid #34495e;
    color: #bdc3c7;
}


/* Responsive */

@media (max-width: 1024px) {
    .header-container {
        padding: 20px 30px;
    }
    nav ul {
        gap: 25px;
    }
    nav a {
        font-size: 15px;
    }
    .product-hero-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .feature-row {
        height: 500px;
    }
    .feature-text {
        padding: 40px;
        margin: 40px;
    }
    .feature-text h3 {
        font-size: 32px;
    }
    .substances-list {
        flex-direction: column;
        gap: 30px;
    }
    .plus-sign {
        font-size: 48px;
        padding: 10px 0;
    }
}

@media (max-width: 768px) {
    /* Header Mobile */
    .header-container {
        padding: 15px 20px;
    }
    .logo img {
        height: 50px;
    }
    /* Hide desktop nav, show mobile menu toggle */
    .desktop-nav {
        display: none !important;
    }
    .mobile-menu-toggle {
        display: flex;
    }
    .mobile-nav {
        display: block;
        top: 80px;
    }
    /* Breadcrumb Mobile */
    .breadcrumb {
        margin-top: 80px;
        padding: 15px 20px;
    }
    .breadcrumb a,
    .breadcrumb span {
        font-size: 12px;
    }
    /* Product Hero Mobile */
    .product-hero {
        padding: 40px 20px;
    }
    .specs-section,
    .rofilter-section {
        padding: 40px 20px;
    }
    .section-title {
        padding: 60px 20px 40px;
        font-size: 32px;
    }
    .feature-row {
        height: 400px;
        justify-content: center;
    }
    .feature-row.reverse {
        justify-content: center;
    }
    .feature-text {
        padding: 30px 20px;
        text-align: center !important;
        margin: 20px;
    }
    .feature-text h3 {
        font-size: 26px;
    }
    .feature-text p {
        font-size: 16px;
    }
    .product-info-main h1 {
        font-size: 32px;
    }
    .product-definition {
        height: 350px;
    }
    .definition-title {
        font-size: 28px;
        padding: 0 30px;
    }
    .rofilter-main-title {
        font-size: 26px;
    }
    .rofilter-content {
        padding: 40px 20px;
        min-height: 500px;
    }
    .rofilter-subtitle {
        font-size: 24px;
    }
    .rofilter-features {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .substances-title {
        font-size: 24px;
    }
    .substance-group {
        padding: 25px 20px;
        min-height: 120px;
    }
    .substance-group p {
        font-size: 14px;
        line-height: 1.8;
    }
    /* Mobile Image Replacements */
    .desktop-img {
        display: none !important;
    }
    .mobile-img {
        display: block !important;
    }
    /* Hide Feature 9 on mobile */
    .feature-img-9 {
        display: none !important;
    }
    /* Specifications Mobile */
    .specs-section {
        padding: 60px 20px;
    }
    .specs-table td {
        padding: 15px 20px;
        font-size: 14px;
        display: block;
        width: 100% !important;
    }
    .specs-table td:first-child {
        background: #f8f9fa;
        font-weight: 700;
        border-bottom: none;
        padding-bottom: 10px;
    }
    .specs-table td:last-child {
        padding-top: 5px;
        padding-bottom: 15px;
    }
    .specs-table tr {
        display: block;
        margin-bottom: 10px;
    }
    /* Footer Mobile */
    footer {
        padding: 40px 20px 20px;
    }
    .footer-container {
        grid-template-columns: 1fr;
        gap: 30px;
        margin-bottom: 20px;
    }
    .footer-about {
        grid-column: 1 / -1;
    }
    .footer-about h3 {
        font-size: 20px;
        margin-bottom: 15px;
    }
    .footer-about p {
        font-size: 14px;
    }
    .footer-links h4 {
        font-size: 16px;
        margin-bottom: 15px;
    }
    .footer-links a {
        font-size: 14px;
        margin-bottom: 8px;
    }
    .footer-links ul {
        padding-left: 0;
    }
    .footer-links ul li {
        font-size: 14px;
        margin-bottom: 8px;
    }
    .footer-bottom {
        padding-top: 20px;
        font-size: 13px;
    }
}


/* Small Mobile (max-width: 480px) */

@media (max-width: 480px) {
    .header-container {
        padding: 15px 15px;
    }
    .breadcrumb {
        padding: 10px 15px;
    }
    .breadcrumb a,
    .breadcrumb span {
        font-size: 11px;
    }
    .product-hero {
        padding: 30px 15px;
    }
    .section-title {
        padding: 50px 15px 30px;
        font-size: 24px;
    }
    .specs-section {
        padding: 50px 15px;
    }
    .specs-table td {
        padding: 12px 15px;
        font-size: 13px;
    }
    .specs-table td:first-child {
        font-size: 13px;
    }
    .specs-table td:last-child {
        font-size: 13px;
    }
    .rofilter-section {
        padding: 50px 15px;
    }
    .rofilter-main-title {
        font-size: 22px;
    }
    .rofilter-content {
        padding: 30px 15px;
    }
    .rofilter-subtitle {
        font-size: 20px;
    }
    footer {
        padding: 30px 15px 15px;
    }
    .footer-container {
        grid-template-columns: 1fr;
        gap: 25px;
        margin-bottom: 15px;
    }
    .footer-about {
        grid-column: 1;
    }
    .footer-about h3 {
        font-size: 18px;
        margin-bottom: 12px;
    }
    .footer-about p {
        font-size: 13px;
        line-height: 1.6;
    }
    .footer-links h4 {
        font-size: 15px;
        margin-bottom: 12px;
    }
    .footer-links a,
    .footer-links ul li {
        font-size: 13px;
        margin-bottom: 6px;
    }
    .footer-bottom {
        padding-top: 15px;
        font-size: 12px;
    }
}


/* ============================================
   Related Products Section - Option 2
   간단한 추천 박스 스타일
   ============================================ */

.related-simple-section {
    padding: 60px 50px;
    background: white;
    border-top: 1px solid #e0e0e0;
}

.related-simple-container {
    max-width: 1000px;
    margin: 0 auto;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
}

.related-simple-header {
    padding: 30px;
    text-align: center;
    background: white;
    border-bottom: 2px solid #0099dc;
}

.related-simple-header h3 {
    font-size: 28px;
    font-weight: 600;
    color: #333;
    margin: 0;
}

.related-simple-list {
    padding: 20px;
}

.related-simple-item {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 20px;
    background: white;
    border-radius: 10px;
    margin-bottom: 15px;
    text-decoration: none;
    transition: all 0.3s;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.related-simple-item:last-child {
    margin-bottom: 0;
}

.related-simple-item:hover {
    transform: translateX(8px);
    box-shadow: 0 4px 15px rgba(0, 153, 220, 0.15);
}

.item-icon {
    font-size: 32px;
    min-width: 50px;
    text-align: center;
}

.item-content {
    flex: 1;
}

.item-content h4 {
    font-size: 20px;
    font-weight: 600;
    color: #0099dc;
    margin: 0 0 5px 0;
}

.item-content p {
    font-size: 14px;
    color: #666;
    margin: 0;
}

.item-price {
    text-align: right;
}

.item-price span {
    font-size: 18px;
    font-weight: 600;
    color: #333;
}

.item-arrow {
    font-size: 24px;
    color: #0099dc;
    min-width: 30px;
    text-align: center;
}

.related-simple-footer {
    padding: 25px 30px;
    text-align: center;
    background: white;
    border-top: 1px solid #e0e0e0;
}

.view-all-link {
    color: #0099dc;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: color 0.3s;
}

.view-all-link:hover {
    color: #0077b3;
}


/* Related Products - Mobile Responsive */

@media (max-width: 768px) {
    .related-simple-section {
        padding: 40px 20px;
    }
    .related-simple-header h3 {
        font-size: 22px;
    }
    .related-simple-item {
        flex-wrap: wrap;
        gap: 15px;
    }
    .item-icon {
        font-size: 28px;
        min-width: 40px;
    }
    .item-content h4 {
        font-size: 18px;
    }
    .item-content p {
        font-size: 13px;
    }
    .item-price {
        order: 4;
        width: 100%;
        text-align: left;
        padding-left: 60px;
    }
    .item-arrow {
        order: 3;
    }
}

@media (max-width: 480px) {
    .related-simple-header {
        padding: 20px;
    }
    .related-simple-header h3 {
        font-size: 20px;
    }
    .related-simple-list {
        padding: 15px;
    }
    .related-simple-item {
        padding: 15px;
    }
    .item-icon {
        font-size: 24px;
        min-width: 35px;
    }
    .item-content h4 {
        font-size: 16px;
    }
    .item-content p {
        font-size: 12px;
    }
    .item-price span {
        font-size: 16px;
    }
}