/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.7;
    color: #1e293b;
    background-color: #ffffff;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: #0f172a;
}

h1 {
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.01em;
}

h3 {
    font-size: 1.5rem;
    font-weight: 600;
}

p {
    margin-bottom: 1rem;
    line-height: 1.7;
    color: #475569;
}

.emphasis {
    font-weight: 500;
    color: #1e293b;
    font-size: 1.05rem;
}

/* Content Blocks */
.content-block {
    max-width: 900px;
    margin: 3rem auto;
    text-align: left;
}

.content-block p {
    font-size: 1.05rem;
    margin-bottom: 1.5rem;
}

/* Buttons */
.primary-button, .secondary-button, .cta-button, .product-button {
    display: inline-block;
    padding: 14px 32px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    text-align: center;
}

.primary-button, .cta-button {
    background: #0f172a;
    color: white;
    border-color: #0f172a;
}

.primary-button:hover, .cta-button:hover {
    background: #1e293b;
    border-color: #1e293b;
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(15, 23, 42, 0.25);
}

.secondary-button {
    background: transparent;
    color: #0f172a;
    border: 2px solid #cbd5e1;
}

.secondary-button:hover {
    background: #f8fafc;
    border-color: #94a3b8;
    transform: translateY(-2px);
}

.large {
    padding: 18px 40px;
    font-size: 1.1rem;
}

.product-button {
    width: 100%;
    background: #0f172a;
    color: white;
    margin-top: 1.5rem;
    border: 2px solid #0f172a;
}

.product-button:hover {
    background: #1e293b;
    border-color: #1e293b;
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(15, 23, 42, 0.25);
}

.product-button.primary {
    background: #1e40af;
    border-color: #1e40af;
}

.product-button.primary:hover {
    background: #1e3a8a;
    border-color: #1e3a8a;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    border-bottom: 1px solid #e2e8f0;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 24px;
}

.nav-brand h2 {
    color: #0f172a;
    margin: 0;
    font-size: 1.5rem;
    font-weight: 700;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2.5rem;
}

.nav-links a {
    text-decoration: none;
    color: #475569;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: #0f172a;
}

.nav-links .cta-button {
    padding: 10px 24px;
    background: #0f172a;
    color: white;
    border-radius: 6px;
    font-size: 0.95rem;
}

.nav-links .cta-button:hover {
    background: #1e293b;
    color: white;
    transform: translateY(-1px);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 2px;
    background: #475569;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding: 140px 0 100px;
    background: linear-gradient(135deg, #f8fafc 0%, #ffffff 100%);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 5rem;
    align-items: center;
}

.hero-text h1 {
    color: #0f172a;
    margin-bottom: 1.25rem;
}

.hero-subtitle {
    font-size: 1.35rem;
    font-weight: 600;
    color: #1e40af;
    margin-bottom: 1.75rem;
    line-height: 1.5;
}

.hero-description {
    font-size: 1.1rem;
    color: #475569;
    margin-bottom: 2.5rem;
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: 1.25rem;
    flex-wrap: wrap;
}

.hero-image img {
    width: 100%;
    height: auto;
    max-height: 500px;
    aspect-ratio: 1093 / 684;
    object-fit: cover;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.12);
    display: block;
    background: linear-gradient(90deg, #f1f5f9 25%, #e2e8f0 50%, #f1f5f9 75%);
    background-size: 200% 100%;
}

/* Problem Section */
.problem-section {
    padding: 100px 0;
    background: #ffffff;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.section-header h2 {
    color: #0f172a;
    margin-bottom: 1.25rem;
}

.section-header p {
    font-size: 1.15rem;
    color: #64748b;
    line-height: 1.7;
}

.solution-highlight {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: white;
    padding: 3.5rem;
    border-radius: 16px;
    text-align: center;
    margin-top: 4rem;
    box-shadow: 0 20px 60px rgba(15, 23, 42, 0.15);
}

.solution-highlight h3 {
    font-size: 1.75rem;
    margin-bottom: 1.25rem;
    color: white;
}

.solution-highlight p {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.9);
    margin: 0;
}

/* Science Section */
.science-section {
    padding: 100px 0;
    background: #f8fafc;
}

/* Video Container */
.video-container {
    margin: 4rem 0;
    text-align: center;
}

.video-wrapper {
    position: relative;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding-bottom: 56.25%;
    height: 0;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
    background: #000;
}

.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.video-caption {
    margin-top: 1.25rem;
    font-size: 0.95rem;
    color: #64748b;
    font-style: italic;
}

/* Infographic Section */
.infographic-section {
    margin: 4rem 0;
    text-align: center;
}

.infographic-section h3 {
    font-size: 2rem;
    color: #0f172a;
    margin-bottom: 3rem;
}

.infographic-grid {
    display: grid;
    gap: 3rem;
    max-width: 1100px;
    margin: 0 auto;
}

.infographic-item {
    background: #f8fafc;
    border-radius: 16px;
    padding: 2rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    will-change: transform;
    backface-visibility: hidden;
    -webkit-font-smoothing: antialiased;
}

.infographic-item:hover {
    transform: translateY(-4px) translateZ(0);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

.infographic-item img {
    width: 100%;
    height: auto;
    border-radius: 12px;
    display: block;
    margin-bottom: 1rem;
    object-fit: contain;
    background: #f1f5f9;
    /* Average aspect ratio for both infographics (1200x675 and 1200x469) */
    aspect-ratio: 2 / 1;
    min-height: 300px;
    /* Prevent disappearing during load/scroll */
    opacity: 1 !important;
    visibility: visible !important;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transform: translateZ(0);
    -webkit-transform: translateZ(0);
}

.infographic-caption {
    font-size: 0.95rem;
    color: #64748b;
    font-style: italic;
    margin-top: 1rem;
}

.science-mechanisms {
    display: grid;
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.mechanism {
    display: flex;
    align-items: flex-start;
    gap: 2.5rem;
    background: white;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid #e2e8f0;
}

.mechanism:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

.mechanism-number {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: white;
    width: 64px;
    height: 64px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    font-weight: 700;
    flex-shrink: 0;
}

.mechanism-content h3 {
    color: #0f172a;
    margin-bottom: 0.75rem;
    font-size: 1.35rem;
}

.mechanism-content p {
    color: #475569;
    margin: 0;
    line-height: 1.8;
}

/* Benefits Section */
.benefits-section {
    padding: 100px 0;
    background: white;
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2.5rem;
    margin-bottom: 4rem;
}

.benefit-card {
    background: #f8fafc;
    padding: 3rem;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.benefit-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.1);
    border-color: #cbd5e1;
}

.benefit-icon {
    color: #1e40af;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: rgba(30, 64, 175, 0.1);
    border-radius: 12px;
}

.benefit-icon svg {
    width: 36px;
    height: 36px;
}

.benefit-card h3 {
    color: #0f172a;
    margin-bottom: 0.75rem;
    font-size: 1.35rem;
}

.benefit-intro {
    font-weight: 600;
    color: #1e40af;
    font-size: 1.05rem;
    margin-bottom: 1rem;
}

.benefit-card p {
    color: #475569;
    line-height: 1.8;
}

/* Safety Section */
.safety-section {
    padding: 100px 0;
    background: #f8fafc;
}

.safety-principles {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.safety-card {
    background: white;
    padding: 2.5rem;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.safety-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

.safety-icon {
    color: #0f172a;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.safety-icon svg {
    width: 48px;
    height: 48px;
}

.safety-card h3 {
    color: #0f172a;
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

.safety-card p {
    color: #475569;
    line-height: 1.8;
    margin: 0;
}

/* Products Section */
.products-section {
    padding: 100px 0;
    background: white;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
    gap: 3rem;
    margin-top: 3rem;
}

.product-card {
    background: #f8fafc;
    border-radius: 16px;
    padding: 2.5rem;
    position: relative;
    border: 2px solid #e2e8f0;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.product-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.12);
    border-color: #cbd5e1;
}

.product-card.featured {
    border-color: #1e40af;
    background: linear-gradient(135deg, #f8fafc 0%, #eff6ff 100%);
    box-shadow: 0 12px 40px rgba(30, 64, 175, 0.1);
}

.product-badge {
    position: absolute;
    top: -12px;
    right: 24px;
    background: #0f172a;
    color: white;
    padding: 0.5rem 1.25rem;
    border-radius: 24px;
    font-size: 0.875rem;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(15, 23, 42, 0.3);
}

.product-badge.professional {
    background: #1e40af;
}

.product-image {
    margin-bottom: 2rem;
}

.product-image img {
    width: 100%;
    height: 240px;
    object-fit: cover;
    border-radius: 12px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.product-card h3 {
    color: #0f172a;
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
}

.product-subtitle {
    color: #1e40af;
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 1rem;
}

.product-description {
    color: #475569;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.product-features {
    list-style: none;
    margin-bottom: 1.5rem;
}

.product-features li {
    padding: 0.75rem 0;
    position: relative;
    padding-left: 2rem;
    color: #334155;
    line-height: 1.6;
}

.product-features li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #1e40af;
    font-weight: bold;
    font-size: 1.1rem;
}

.product-details {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid #e2e8f0;
}

.product-details p {
    font-size: 0.95rem;
    color: #64748b;
    line-height: 1.7;
}

/* FAQ Section */
.faq-section {
    padding: 100px 0;
    background: #f8fafc;
}

.faq-list {
    max-width: 900px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    border-radius: 12px;
    margin-bottom: 1.25rem;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    border: 1px solid #e2e8f0;
    transition: box-shadow 0.3s ease;
}

.faq-item:hover {
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

.faq-question {
    width: 100%;
    padding: 1.75rem 2rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background-color 0.3s ease;
    background: transparent;
    border: none;
    text-align: left;
    font-family: inherit;
}

.faq-question:hover {
    background: #f8fafc;
}

.faq-question h3 {
    margin: 0;
    color: #0f172a;
    font-size: 1.15rem;
    font-weight: 600;
}

.faq-toggle {
    font-size: 1.5rem;
    font-weight: 300;
    color: #0f172a;
    transition: transform 0.3s ease;
    flex-shrink: 0;
    margin-left: 1rem;
}

.faq-answer {
    padding: 0 2rem;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
}

.faq-answer p {
    color: #475569;
    line-height: 1.8;
}

.faq-answer ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.faq-answer li {
    color: #475569;
    margin-bottom: 0.5rem;
    line-height: 1.7;
}

.faq-item.active .faq-answer {
    padding: 0 2rem 1.75rem;
    max-height: 600px;
}

.faq-item.active .faq-toggle {
    transform: rotate(45deg);
}

/* CTA Section */
.cta-section {
    padding: 100px 0;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: white;
    text-align: center;
}

.cta-content h2 {
    color: white;
    margin-bottom: 1.25rem;
    font-size: 2.75rem;
}

.cta-content p {
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    color: rgba(255, 255, 255, 0.9);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.cta-buttons {
    display: flex;
    gap: 1.25rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 2rem;
}

.cta-buttons .primary-button {
    background: white;
    color: #0f172a;
    border-color: white;
}

.cta-buttons .primary-button:hover {
    background: #f8fafc;
    color: #0f172a;
}

.cta-buttons .secondary-button {
    background: transparent;
    color: white;
    border-color: rgba(255, 255, 255, 0.5);
}

.cta-buttons .secondary-button:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: white;
}

.guarantee {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.7);
}

/* Footer */
.footer {
    background: #0f172a;
    color: white;
    padding: 80px 0 32px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer-brand h3 {
    color: white;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    margin: 0;
    line-height: 1.7;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3rem;
}

.footer-column h4 {
    margin-bottom: 1.25rem;
    color: white;
    font-size: 1rem;
    font-weight: 600;
}

.footer-column a {
    display: block;
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    margin-bottom: 0.75rem;
    transition: color 0.3s ease;
    font-size: 0.95rem;
}

.footer-column a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 2rem;
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    h1 {
        font-size: 2.5rem;
    }

    h2 {
        font-size: 2rem;
    }

    .nav-links {
        display: none;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero {
        padding: 120px 0 80px;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 3rem;
        text-align: center;
    }

    .hero-cta {
        justify-content: center;
    }

    .hero-image img {
        height: auto;
        max-height: 320px;
        aspect-ratio: 1093 / 684;
    }

    .benefits-grid,
    .safety-principles {
        grid-template-columns: 1fr;
    }

    .products-grid {
        grid-template-columns: 1fr;
    }

    .mechanism {
        flex-direction: column;
        text-align: center;
        padding: 2rem;
    }

    .mechanism-number {
        margin: 0 auto;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .footer-links {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .cta-buttons .primary-button,
    .cta-buttons .secondary-button {
        width: 100%;
        max-width: 320px;
    }

    .problem-section,
    .science-section,
    .benefits-section,
    .safety-section,
    .products-section,
    .faq-section,
    .cta-section {
        padding: 80px 0;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.75rem;
    }

    .hero {
        padding: 100px 0 60px;
    }

    .product-card,
    .benefit-card,
    .safety-card {
        padding: 2rem;
    }

    .mechanism {
        padding: 1.5rem;
    }

    .section-header h2 {
        font-size: 1.75rem;
    }
}