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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.about-nav {
    background-color: #620000;
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.about-nav .nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.about-nav .logo h1 {
    color: #fff;
    font-size: 22px;
    margin-bottom: 2px;
}

.about-nav .logo p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 12px;
}

.about-nav .nav-links {
    display: flex;
    list-style: none;
    gap: 25px;
}

.about-nav .nav-links a {
    color: #fff;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
    padding: 5px 0;
    border-bottom: 2px solid transparent;
}

.about-nav .nav-links a:hover,
.about-nav .nav-links a.active {
    color: #ffd700;
    border-bottom-color: #ffd700;
}

.about-nav .contact-btn {
    background-color: #e63946;
    color: #fff;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 4px;
    font-size: 14px;
    transition: background-color 0.3s;
}

.about-nav .contact-btn:hover {
    background-color: #c5303c;
}

.about-nav .contact-btn i {
    margin-right: 5px;
}

.about-hero {
    background: linear-gradient(135deg, #620000 0%, #8b0000 100%);
    padding: 80px 0;
    text-align: center;
    color: #fff;
}

.about-hero h2 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: 4px;
}

.about-hero p {
    font-size: 18px;
    letter-spacing: 3px;
    opacity: 0.8;
}

.about-hero .hero-line {
    width: 60px;
    height: 3px;
    background-color: #ffd700;
    margin: 20px auto 0;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header p {
    font-size: 24px;
    font-weight: 700;
    color: #620000;
    letter-spacing: 2px;
    margin-bottom: 10px;
}

.section-header h2 {
    font-size: 18px;
    font-weight: 300;
    letter-spacing: 3px;
    color: #999;
}

.company-intro .section-header p {
    color: #e63946;
}

.company-intro .section-header h2 {
    color: rgba(255, 255, 255, 0.5);
}

.company-intro {
    padding: 80px 0;
    background-color: #1f1f1f;
}

.company-intro .intro-text h2 {
    color: #fff;
}

.company-intro .intro-text .intro-lead {
    color: #d0d0d0;
}

.company-intro .intro-text p {
    color: #b0b0b0;
}

.company-intro .intro-text .section-label span:last-child {
    color: #e63946;
}

.company-intro .intro-images .main-image,
.company-intro .intro-images .sub-images img {
    border: 2px solid rgba(255, 255, 255, 0.1);
}

.company-intro .intro-images .main-image:hover,
.company-intro .intro-images .sub-images img:hover {
    border-color: rgba(230, 57, 70, 0.5);
}

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

.intro-text .section-label {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
}

.intro-text .label-line {
    width: 40px;
    height: 2px;
    background-color: #e63946;
}

.intro-text .section-label span:last-child {
    font-size: 14px;
    color: #e63946;
    letter-spacing: 2px;
    font-weight: 600;
}

.intro-text h2 {
    font-size: 32px;
    color: #1a1a1a;
    margin-bottom: 25px;
    line-height: 1.3;
}

.intro-text .intro-lead {
    font-size: 17px;
    color: #333;
    line-height: 1.8;
    margin-bottom: 20px;
    font-weight: 500;
}

.intro-text p {
    font-size: 15px;
    color: #666;
    line-height: 1.8;
    margin-bottom: 15px;
}

.intro-images {
    position: relative;
}

.intro-images .main-image {
    width: 100%;
    height: 400px;
    object-fit: cover;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.intro-images .main-image:hover {
    transform: scale(1.02);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.intro-images .sub-images {
    display: flex;
    gap: 20px;
    margin-top: 25px;
    align-items: stretch;
}

.intro-images .sub-images img {
    width: 240px;
    height: 180px;
    object-fit: cover;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.intro-images .sub-images img:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}

.experience-badge {
    background: linear-gradient(135deg, #620000, #8b0000);
    color: #fff;
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-width: 120px;
}

.experience-badge span {
    font-size: 42px;
    font-weight: 700;
    line-height: 1;
}

.experience-badge p {
    font-size: 14px;
    margin-top: 5px;
}

.company-history {
    padding: 80px 0;
    background-color: #f8f8f8;
}

.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
    padding-left: 60px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 20px;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(180deg, #620000, #e63946);
}

.timeline-item {
    position: relative;
    margin-bottom: 50px;
}

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

.timeline-year {
    position: absolute;
    left: -60px;
    top: 0;
    width: 50px;
    height: 50px;
    background-color: #620000;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 600;
}

.timeline-content {
    background-color: #fff;
    padding: 25px 30px;
    border-radius: 8px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.timeline-content:hover {
    transform: translateX(5px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.timeline-content h3 {
    font-size: 20px;
    color: #1a1a1a;
    margin-bottom: 10px;
}

.timeline-content p {
    font-size: 14px;
    color: #666;
    line-height: 1.8;
}

.mission-vision {
    padding: 80px 0;
    background-color: #fff;
}

.mv-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.mv-item {
    text-align: center;
    padding: 40px 30px;
    background-color: #f8f8f8;
    border-radius: 12px;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.mv-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 40px rgba(98, 0, 0, 0.15);
    border-color: #e63946;
}

.mv-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #620000, #8b0000);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
}

.mv-icon i {
    font-size: 32px;
    color: #fff;
}

.mv-item h3 {
    font-size: 22px;
    color: #1a1a1a;
    margin-bottom: 15px;
}

.mv-item p {
    font-size: 14px;
    color: #666;
    line-height: 1.8;
}

.company-advantages {
    padding: 80px 0;
    background-color: #f8f8f8;
    background-image: url('../images/cases/youshi.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    position: relative;
}

.company-advantages::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(255, 255, 255, 0.95);
}

.company-advantages .container {
    position: relative;
    z-index: 1;
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.advantage-card {
    background-color: #fff;
    padding: 35px 30px;
    border-radius: 12px;
    box-shadow: 0 5px 25px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border-top: 4px solid transparent;
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.12);
    border-top-color: #e63946;
}

.advantage-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, #620000, #8b0000);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    transition: transform 0.3s;
}

.advantage-card:hover .advantage-icon {
    transform: scale(1.1);
}

.advantage-icon i {
    font-size: 30px;
    color: #fff;
}

.advantage-card h3 {
    font-size: 22px;
    color: #1a1a1a;
    margin-bottom: 15px;
}

.advantage-card p {
    font-size: 14px;
    color: #666;
    line-height: 1.8;
    margin-bottom: 20px;
}

.advantage-list {
    list-style: none;
}

.advantage-list li {
    font-size: 14px;
    color: #555;
    padding: 8px 0;
    display: flex;
    align-items: center;
    border-top: 1px dashed #eee;
}

.advantage-list li:first-child {
    border-top: none;
}

.advantage-list i {
    color: #e63946;
    margin-right: 10px;
}

.data-showcase {
    padding: 80px 0;
    background: linear-gradient(135deg, #620000 0%, #8b0000 100%);
}

.data-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 30px;
    text-align: center;
}

.data-item h3 {
    font-size: 42px;
    color: #fff;
    font-weight: 700;
    margin-bottom: 10px;
}

.data-item p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
    letter-spacing: 1px;
}

.cta-section {
    padding: 80px 0;
    background-color: #fff;
    text-align: center;
}

.cta-section h2 {
    font-size: 32px;
    color: #1a1a1a;
    margin-bottom: 15px;
}

.cta-section p {
    font-size: 16px;
    color: #666;
    margin-bottom: 35px;
}

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

.btn-primary {
    display: inline-block;
    padding: 15px 35px;
    background-color: #e63946;
    color: #fff;
    text-decoration: none;
    font-size: 15px;
    font-weight: 600;
    border-radius: 4px;
    transition: all 0.3s ease;
    border: 2px solid #e63946;
    cursor: pointer;
}

.btn-primary:hover {
    background-color: #c5303c;
    border-color: #c5303c;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(230, 57, 70, 0.3);
}

.btn-primary i {
    margin-right: 8px;
}

.btn-secondary {
    display: inline-block;
    padding: 15px 35px;
    background-color: transparent;
    color: #620000;
    text-decoration: none;
    font-size: 15px;
    font-weight: 600;
    border-radius: 4px;
    transition: all 0.3s ease;
    border: 2px solid #620000;
    cursor: pointer;
}

.btn-secondary:hover {
    background-color: #620000;
    color: #fff;
    transform: translateY(-2px);
}

.btn-secondary i {
    margin-right: 8px;
}

.about-footer {
    background-color: #1a1a1a;
    padding: 60px 0 0;
    color: #fff;
}

.about-footer .footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 2fr;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.about-footer .footer-section h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: #fff;
}

.about-footer .footer-section h4 {
    font-size: 16px;
    margin-bottom: 20px;
    color: #fff;
}

.about-footer .footer-section p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
    margin-bottom: 8px;
}

.about-footer .footer-section ul {
    list-style: none;
}

.about-footer .footer-section ul li {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
    line-height: 2;
}

.about-footer .footer-section ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s;
}

.about-footer .footer-section ul li a:hover {
    color: #e63946;
}

.about-footer .footer-section ul li i {
    color: #e63946;
    margin-right: 8px;
}

.about-footer .footer-bottom {
    padding: 20px 0;
    text-align: center;
}

.about-footer .footer-bottom p {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.5);
}

.about-footer .footer-bottom a {
    color: rgba(255, 255, 255, 0.5);
    text-decoration: none;
    transition: color 0.3s;
}

.about-footer .footer-bottom a:hover {
    color: #e63946;
}

@media (max-width: 992px) {
    .about-nav .nav-links {
        gap: 18px;
    }

    .about-nav .nav-links a {
        font-size: 13px;
    }

    .intro-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

    .about-footer .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

@media (max-width: 768px) {
    .about-nav .nav-links {
        display: none;
    }

    .about-nav .logo h1 {
        font-size: 18px;
    }

    .about-nav .logo p {
        font-size: 11px;
    }

    .about-hero h2 {
        font-size: 32px;
    }

    .about-hero p {
        font-size: 14px;
    }

    .intro-text h2 {
        font-size: 24px;
    }

    .intro-images .sub-images img {
        width: 180px;
        height: 140px;
    }

    .experience-badge {
        min-width: 110px;
        padding: 15px;
    }

    .experience-badge span {
        font-size: 32px;
    }

    .timeline {
        padding-left: 50px;
    }

    .timeline-year {
        left: -50px;
        width: 40px;
        height: 40px;
        font-size: 12px;
    }

    .timeline::before {
        left: 15px;
    }

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

    .cta-buttons a {
        width: 100%;
        max-width: 280px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .about-nav .contact-btn {
        font-size: 12px;
        padding: 8px 15px;
    }

    .about-hero {
        padding: 50px 0;
    }

    .about-hero h2 {
        font-size: 28px;
    }

    .intro-images .main-image {
        height: 250px;
    }

    .intro-images .sub-images {
        flex-direction: column;
        align-items: stretch;
    }

    .intro-images .sub-images img {
        width: 100%;
        height: 180px;
    }

    .experience-badge {
        flex-direction: row;
        justify-content: center;
        gap: 15px;
    }
}

.image-lightbox {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 9999;
    display: none;
    justify-content: center;
    align-items: center;
}

.image-lightbox.active {
    display: flex;
}

.lightbox-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(5px);
}

.lightbox-content {
    position: relative;
    max-width: 90%;
    max-height: 90%;
    z-index: 1;
}

.lightbox-content img {
    max-width: 100%;
    max-height: 85vh;
    border-radius: 8px;
    box-shadow: 0 0 50px rgba(255, 255, 255, 0.2);
}

.lightbox-close {
    position: absolute;
    top: -40px;
    right: 0;
    background: none;
    border: none;
    color: #fff;
    font-size: 28px;
    cursor: pointer;
    padding: 10px;
    transition: transform 0.3s;
}

.lightbox-close:hover {
    transform: rotate(90deg);
}

@media (max-width: 768px) {
    .lightbox-close {
        top: -50px;
        right: 50%;
        transform: translateX(50%);
    }

    .lightbox-close:hover {
        transform: translateX(50%) rotate(90deg);
    }
}