/* ==========================================
   卢宁建筑事务所 - Lu Ning Architecture
   中英文双语网站样式
   ========================================== */

/* CSS Variables */
:root {
    --primary-color: #1a1a1a;
    --secondary-color: #c9a96e;
    --accent-color: #8b7355;
    --text-color: #333;
    --text-light: #666;
    --bg-color: #fff;
    --bg-light: #f8f8f8;
    --bg-dark: #1a1a1a;
    --border-color: #e0e0e0;
    --shadow: 0 4px 20px rgba(0,0,0,0.1);
    --shadow-hover: 0 8px 30px rgba(0,0,0,0.15);
    --transition: all 0.3s ease;
    --font-en: 'Playfair Display', serif;
    --font-cn: 'Noto Sans SC', sans-serif;
    --font-body: 'Open Sans', 'Noto Sans SC', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-color);
    background-color: var(--bg-color);
}

/* Language Toggle - 语言切换 */
.lang-en { display: block; }
.lang-cn { display: none; }

body.chinese .lang-en { display: none; }
body.chinese .lang-cn { display: block; }

/* 内联语言切换 */
span.lang-en, a.lang-en { display: inline; }
span.lang-cn, a.lang-cn { display: none; }

body.chinese span.lang-en, body.chinese a.lang-en { display: none; }
body.chinese span.lang-cn, body.chinese a.lang-cn { display: inline; }

/* Header */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.98);
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
    transition: var(--transition);
}

header.scrolled {
    background: rgba(255,255,255,0.98);
    box-shadow: 0 2px 30px rgba(0,0,0,0.12);
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 90px;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 15px;
    text-decoration: none;
    color: var(--primary-color);
}

.logo-icon {
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-icon svg {
    width: 100%;
    height: 100%;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-name-en {
    font-family: var(--font-en);
    font-size: 20px;
    font-weight: 600;
    letter-spacing: 2px;
    color: var(--primary-color);
}

.logo-name-cn {
    font-family: var(--font-cn);
    font-size: 12px;
    color: var(--text-light);
    letter-spacing: 3px;
}

.logo a:hover {
    opacity: 0.8;
}

/* Navigation */
nav {
    display: flex;
    align-items: center;
    gap: 40px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 35px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 1px;
    text-transform: uppercase;
    position: relative;
    padding: 5px 0;
    transition: var(--transition);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--secondary-color);
    transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--secondary-color);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

/* Language Switcher */
.lang-switch {
    display: flex;
    gap: 10px;
    padding-left: 30px;
    border-left: 1px solid var(--border-color);
}

.lang-switch button {
    background: none;
    border: none;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    padding: 5px 10px;
    transition: var(--transition);
}

.lang-switch button.active {
    color: var(--secondary-color);
    font-weight: 600;
}

.lang-switch button:hover {
    color: var(--secondary-color);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 10px;
}

.menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

/* Hero Section */
.hero {
    height: 100vh;
    min-height: 700px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background: linear-gradient(135deg, #1a1a1a 0%, #2d2d2d 100%);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.4;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to bottom, rgba(0,0,0,0.3), rgba(0,0,0,0.6));
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: #fff;
    max-width: 900px;
    padding: 0 40px;
}

.hero h1 {
    font-family: var(--font-en);
    font-size: 72px;
    font-weight: 400;
    letter-spacing: 8px;
    margin-bottom: 20px;
    text-transform: uppercase;
}

.hero .subtitle {
    font-family: var(--font-cn);
    font-size: 24px;
    letter-spacing: 10px;
    margin-bottom: 30px;
    color: var(--secondary-color);
}

.hero p {
    font-size: 18px;
    line-height: 1.8;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto 40px;
}

.hero-btn {
    display: inline-block;
    padding: 15px 50px;
    border: 2px solid var(--secondary-color);
    color: #fff;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 2px;
    text-transform: uppercase;
    transition: var(--transition);
}

.hero-btn:hover {
    background: var(--secondary-color);
    color: var(--primary-color);
}

/* Page Header */
.page-header {
    padding: 180px 0 100px;
    background: linear-gradient(135deg, #1a1a1a 0%, #2d2d2d 100%);
    text-align: center;
    color: #fff;
}

.page-header h1 {
    font-family: var(--font-en);
    font-size: 48px;
    font-weight: 400;
    letter-spacing: 5px;
    margin-bottom: 15px;
    text-transform: uppercase;
}

.page-header .subtitle {
    font-family: var(--font-cn);
    font-size: 20px;
    color: var(--secondary-color);
    letter-spacing: 5px;
}

/* Sections */
section {
    padding: 100px 0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-family: var(--font-en);
    font-size: 42px;
    font-weight: 400;
    color: var(--primary-color);
    margin-bottom: 15px;
    letter-spacing: 3px;
}

.section-header .subtitle {
    font-family: var(--font-cn);
    font-size: 18px;
    color: var(--secondary-color);
    letter-spacing: 5px;
}

.section-header p {
    max-width: 700px;
    margin: 20px auto 0;
    color: var(--text-light);
}

/* About Section */
.about-section {
    background: var(--bg-light);
}

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

.about-image {
    position: relative;
}

.about-image img {
    width: 100%;
    height: 500px;
    object-fit: cover;
}

.about-image::before {
    content: '';
    position: absolute;
    top: 20px;
    left: 20px;
    right: -20px;
    bottom: -20px;
    border: 2px solid var(--secondary-color);
    z-index: -1;
}

.about-content h3 {
    font-family: var(--font-en);
    font-size: 32px;
    font-weight: 400;
    margin-bottom: 25px;
    color: var(--primary-color);
}

.about-content p {
    color: var(--text-light);
    margin-bottom: 20px;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 30px;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 15px;
}

.feature-item i {
    color: var(--secondary-color);
    font-size: 20px;
}

/* Services Section */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.service-card {
    background: #fff;
    padding: 50px 40px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.service-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-5px);
    border-color: var(--secondary-color);
}

.service-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 25px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-light);
    border-radius: 50%;
    transition: var(--transition);
}

.service-card:hover .service-icon {
    background: var(--secondary-color);
}

.service-icon i {
    font-size: 32px;
    color: var(--secondary-color);
    transition: var(--transition);
}

.service-card:hover .service-icon i {
    color: #fff;
}

.service-card h3 {
    font-family: var(--font-en);
    font-size: 22px;
    font-weight: 500;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.service-card p {
    color: var(--text-light);
    font-size: 15px;
}

/* Projects Section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.project-card {
    position: relative;
    overflow: hidden;
    cursor: pointer;
}

.project-card img {
    width: 100%;
    height: 350px;
    object-fit: cover;
    transition: var(--transition);
}

.project-card:hover img {
    transform: scale(1.1);
}

.project-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.9) 0%, rgba(0,0,0,0) 60%);
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 30px;
    transition: var(--transition);
}

.project-card:hover .project-overlay {
    background: linear-gradient(to top, rgba(0,0,0,0.95) 0%, rgba(0,0,0,0.3) 100%);
}

.project-overlay h3 {
    color: #fff;
    font-family: var(--font-en);
    font-size: 20px;
    font-weight: 500;
    margin-bottom: 5px;
}

.project-overlay span {
    color: var(--secondary-color);
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* Project Categories Filter */
.project-filter {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 50px;
    flex-wrap: wrap;
}

.filter-btn {
    background: none;
    border: none;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    padding: 10px 25px;
    letter-spacing: 1px;
    text-transform: uppercase;
    transition: var(--transition);
    border-bottom: 2px solid transparent;
}

.filter-btn:hover,
.filter-btn.active {
    color: var(--secondary-color);
    border-color: var(--secondary-color);
}

/* Stats Section */
.stats-section {
    background: var(--bg-dark);
    padding: 80px 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    text-align: center;
}

.stat-item {
    color: #fff;
}

.stat-number {
    font-family: var(--font-en);
    font-size: 60px;
    font-weight: 300;
    color: var(--secondary-color);
    line-height: 1;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 2px;
    opacity: 0.8;
}

/* FAQ Section */
.faq-section {
    background: var(--bg-light);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    margin-bottom: 15px;
    border: 1px solid var(--border-color);
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 25px 30px;
    cursor: pointer;
    transition: var(--transition);
}

.faq-question:hover {
    background: var(--bg-light);
}

.faq-question h3 {
    font-family: var(--font-body);
    font-size: 17px;
    font-weight: 500;
    color: var(--primary-color);
    margin: 0;
}

.faq-question i {
    color: var(--secondary-color);
    transition: var(--transition);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer p {
    padding: 0 30px 25px;
    color: var(--text-light);
    line-height: 1.8;
}

/* Contact Section */
.contact-section {
    background: var(--bg-light);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-info h3 {
    font-family: var(--font-en);
    font-size: 28px;
    font-weight: 400;
    margin-bottom: 30px;
    color: var(--primary-color);
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
}

.contact-item i {
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--secondary-color);
    color: #fff;
    font-size: 20px;
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 5px;
    color: var(--primary-color);
}

.contact-item p {
    color: var(--text-light);
    font-size: 15px;
}

.contact-item a {
    color: var(--text-light);
    text-decoration: none;
    transition: var(--transition);
}

.contact-item a:hover {
    color: var(--secondary-color);
}

/* Contact Form */
.contact-form {
    background: #fff;
    padding: 50px;
    box-shadow: var(--shadow);
}

.contact-form h3 {
    font-family: var(--font-en);
    font-size: 24px;
    font-weight: 400;
    margin-bottom: 30px;
    color: var(--primary-color);
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--primary-color);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 15px;
    border: 1px solid var(--border-color);
    font-family: var(--font-body);
    font-size: 15px;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--secondary-color);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.submit-btn {
    width: 100%;
    padding: 18px;
    background: var(--primary-color);
    color: #fff;
    border: none;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    cursor: pointer;
    transition: var(--transition);
}

.submit-btn:hover {
    background: var(--secondary-color);
}

/* Map */
.map-section {
    height: 450px;
}

.map-section iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* Testimonials */
.testimonials-section {
    background: var(--bg-dark);
    color: #fff;
}

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

.testimonial-card {
    background: rgba(255,255,255,0.05);
    padding: 40px;
    border-left: 4px solid var(--secondary-color);
}

.testimonial-card p {
    font-size: 18px;
    line-height: 1.8;
    font-style: italic;
    margin-bottom: 25px;
    opacity: 0.9;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 15px;
}

.testimonial-author img {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    object-fit: cover;
}

.author-info h4 {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 3px;
}

.author-info span {
    font-size: 14px;
    color: var(--secondary-color);
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--accent-color) 100%);
    padding: 100px 0;
    text-align: center;
    color: #fff;
}

.cta-section h2 {
    font-family: var(--font-en);
    font-size: 42px;
    font-weight: 400;
    margin-bottom: 20px;
}

.cta-section p {
    font-size: 18px;
    max-width: 600px;
    margin: 0 auto 40px;
    opacity: 0.9;
}

.cta-btn {
    display: inline-block;
    padding: 18px 50px;
    background: var(--primary-color);
    color: #fff;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    transition: var(--transition);
}

.cta-btn:hover {
    background: #fff;
    color: var(--primary-color);
}

/* Footer */
footer {
    background: var(--bg-dark);
    color: #fff;
    padding: 80px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-about h3 {
    font-family: var(--font-en);
    font-size: 24px;
    font-weight: 500;
    margin-bottom: 20px;
    color: #fff;
}

.footer-about p {
    color: rgba(255,255,255,0.7);
    line-height: 1.8;
    margin-bottom: 25px;
}

.footer-social {
    display: flex;
    gap: 15px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.1);
    color: #fff;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--secondary-color);
}

.footer-links h4,
.footer-contact h4 {
    font-size: 16px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 25px;
    color: #fff;
}

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

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--secondary-color);
}

.footer-contact p {
    color: rgba(255,255,255,0.7);
    margin-bottom: 15px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.footer-contact i {
    color: var(--secondary-color);
    margin-top: 3px;
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-bottom p {
    color: rgba(255,255,255,0.5);
    font-size: 14px;
}

.footer-bottom a {
    color: var(--secondary-color);
    text-decoration: none;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .header-container {
        padding: 0 30px;
    }

    .nav-links {
        gap: 25px;
    }

    .hero h1 {
        font-size: 56px;
    }

    .services-grid,
    .projects-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px 20px;
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .header-container {
        height: 70px;
    }

    .menu-toggle {
        display: flex;
    }

    nav {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 30px;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
        box-shadow: var(--shadow);
    }

    nav.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-links {
        flex-direction: column;
        text-align: center;
        gap: 20px;
    }

    .lang-switch {
        padding-left: 0;
        border-left: none;
        padding-top: 20px;
        border-top: 1px solid var(--border-color);
        justify-content: center;
    }

    .hero {
        min-height: 600px;
    }

    .hero h1 {
        font-size: 36px;
        letter-spacing: 4px;
    }

    .hero .subtitle {
        font-size: 18px;
    }

    .page-header {
        padding: 140px 0 60px;
    }

    .page-header h1 {
        font-size: 32px;
    }

    section {
        padding: 60px 0;
    }

    .container {
        padding: 0 20px;
    }

    .section-header h2 {
        font-size: 32px;
    }

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

    .about-image::before {
        display: none;
    }

    .services-grid,
    .projects-grid {
        grid-template-columns: 1fr;
    }

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

    .contact-form {
        padding: 30px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

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

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

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 28px;
    }

    .stat-number {
        font-size: 42px;
    }

    .about-features {
        grid-template-columns: 1fr;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeInUp 0.6s ease forwards;
}

/* Utility Classes */
.text-center { text-align: center; }
.mb-0 { margin-bottom: 0; }
.mt-40 { margin-top: 40px; }