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

:root {
    --primary-red: #8B0000;
    --light-red: #A52A2A;
    --dark-red: #660000;
    --white: #FFFFFF;
    --light-gray: #F5F5F5;
    --gray: #E0E0E0;
    --dark-gray: #333333;
    --text-color: #2C2C2C;
}

body {
    font-family: 'Montserrat', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
    scroll-behavior: smooth;
}

body.menu-open {
    overflow: hidden;
}

/* Selection Color */
::selection {
    background: var(--primary-red);
    color: var(--white);
}

::-moz-selection {
    background: var(--primary-red);
    color: var(--white);
}

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

/* Header */
.header {
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo img {
    height: 60px;
    width: auto;
    transition: transform 0.3s ease;
}

.logo img:hover {
    transform: scale(1.05);
}

.nav {
    display: flex;
    gap: 30px;
}

.nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: all 0.3s;
    position: relative;
    padding: 5px 0;
}

.nav a::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--primary-red);
    transition: all 0.3s;
    transform: translateX(-50%);
}

.nav a:hover::before {
    width: 100%;
}

.nav a:hover,
.nav a.active {
    color: var(--primary-red);
}

.nav a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--primary-red);
}

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

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--primary-red);
    transition: 0.3s;
    display: block;
}

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

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

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Hero Section */
.hero {
    position: relative;
    height: 90vh;
    overflow: hidden;
}

.hero-slider {
    height: 100%;
    position: relative;
}

.slide {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

.slide.active {
    opacity: 1;
}

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

.slide-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--white);
    z-index: 2;
    width: 90%;
    max-width: 800px;
}

.slide::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.4);
    z-index: 1;
}

.slide-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    text-shadow: 2px 2px 8px rgba(0,0,0,0.7);
    animation: fadeInUp 1s ease;
}

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

.slide-content p {
    font-size: 1.5rem;
    margin-bottom: 30px;
    text-shadow: 1px 1px 4px rgba(0,0,0,0.5);
    animation: fadeInUp 1s ease 0.2s both;
}

.cta-btn {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-red), var(--dark-red));
    color: var(--white);
    padding: 15px 40px;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: all 0.3s;
    box-shadow: 0 4px 15px rgba(139,0,0,0.3);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 1s ease 0.4s both;
}

.cta-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: left 0.5s;
}

.cta-btn:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 8px 25px rgba(139,0,0,0.5);
}

.cta-btn:hover::before {
    left: 100%;
}

.cta-btn:active {
    transform: translateY(-1px) scale(1.02);
}

.slider-controls {
    position: absolute;
    top: 50%;
    width: 100%;
    display: flex;
    justify-content: space-between;
    padding: 0 20px;
    z-index: 3;
}

.slider-controls button {
    background: rgba(255,255,255,0.3);
    border: none;
    color: var(--white);
    font-size: 3rem;
    width: 50px;
    height: 50px;
    cursor: pointer;
    border-radius: 50%;
    transition: 0.3s;
}

.slider-controls button:hover {
    background: var(--primary-red);
}

.slider-dots {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
    z-index: 3;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
    cursor: pointer;
    transition: 0.3s;
}

.dot.active {
    background: var(--primary-red);
    width: 30px;
    border-radius: 6px;
}

/* Section Styles */
section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 50px;
    color: var(--dark-gray);
    position: relative;
    padding-bottom: 20px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, transparent, var(--primary-red), transparent);
    border-radius: 2px;
}

.section-title::before {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 4px;
    background: var(--primary-red);
    border-radius: 2px;
}

/* About Intro */
.about-intro {
    background: var(--light-gray);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 50px;
    align-items: center;
}

.about-image img {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.about-image img:hover {
    transform: scale(1.02);
    box-shadow: 0 15px 40px rgba(139,0,0,0.2);
}

.about-text h2 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: var(--primary-red);
}

.quote {
    font-style: italic;
    font-size: 1.2rem;
    color: var(--dark-gray);
    margin: 20px 0;
    padding-left: 20px;
    border-left: 4px solid var(--primary-red);
}

.btn-secondary {
    display: inline-block;
    background: transparent;
    color: var(--primary-red);
    padding: 12px 30px;
    text-decoration: none;
    border: 2px solid var(--primary-red);
    border-radius: 50px;
    font-weight: 600;
    margin-top: 20px;
    transition: all 0.3s;
}

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

/* Services */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.service-card {
    background: var(--white);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-red), var(--light-red));
    transform: scaleX(0);
    transition: transform 0.3s;
}

.service-card:hover::before {
    transform: scaleX(1);
}

.service-card:hover {
    transform: translateY(-15px);
    box-shadow: 0 15px 40px rgba(139,0,0,0.2);
}

.service-icon {
    width: 100%;
    height: 200px;
    margin-bottom: 20px;
    overflow: hidden;
    border-radius: 10px;
}

.service-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: 0.3s;
}

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

.service-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--dark-gray);
}

.service-link {
    color: var(--primary-red);
    text-decoration: none;
    font-weight: 600;
    display: inline-block;
    margin-top: 15px;
    transition: 0.3s;
}

.service-link:hover {
    transform: translateX(5px);
}

/* Why Choose Us */
.why-choose {
    background: var(--light-gray);
}

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

.feature {
    text-align: center;
    padding: 30px 20px;
    background: var(--white);
    border-radius: 10px;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.feature:hover {
    box-shadow: 0 10px 30px rgba(139,0,0,0.15);
    border-color: var(--primary-red);
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    height: 150px;
    overflow: hidden;
    border-radius: 10px;
}

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

.feature h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--primary-red);
}

/* Portfolio */
.portfolio-filter {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.filter-btn {
    background: transparent;
    border: 2px solid var(--gray);
    padding: 10px 25px;
    border-radius: 50px;
    cursor: pointer;
    font-weight: 500;
    transition: 0.3s;
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--primary-red);
    color: var(--white);
    border-color: var(--primary-red);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-bottom: 40px;
}

.portfolio-item {
    position: relative;
    overflow: hidden;
    border-radius: 10px;
    cursor: pointer;
    height: 300px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.portfolio-item:hover {
    box-shadow: 0 15px 40px rgba(139,0,0,0.25);
}

.portfolio-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: 0.5s;
}

.portfolio-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(139,0,0,0.9), transparent);
    color: var(--white);
    padding: 30px 20px;
    transform: translateY(100%);
    transition: 0.3s;
}

.portfolio-item:hover .portfolio-overlay {
    transform: translateY(0);
}

.portfolio-item:hover img {
    transform: scale(1.1);
}

.portfolio-overlay h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
}

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

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary-red), var(--dark-red));
    color: var(--white);
    text-align: center;
}

.cta-section h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.cta-section p {
    font-size: 1.2rem;
    margin-bottom: 30px;
}

/* Footer */
.footer {
    background: var(--dark-gray);
    color: var(--white);
    padding: 50px 0 20px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 30px;
}

.footer-logo {
    height: 50px;
    margin-bottom: 15px;
}

.footer h4 {
    color: var(--primary-red);
    margin-bottom: 15px;
}

.footer ul {
    list-style: none;
}

.footer ul li {
    margin-bottom: 10px;
}

.footer a {
    color: var(--white);
    text-decoration: none;
    transition: 0.3s;
}

.footer a:hover {
    color: var(--primary-red);
}

.social-links {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* Floating Contact */
.floating-contact {
    position: fixed;
    right: 20px;
    bottom: 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    z-index: 999;
}

.float-btn {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    text-decoration: none;
    font-weight: bold;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    transition: all 0.3s ease;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% {
        box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    }
    50% {
        box-shadow: 0 4px 25px rgba(139,0,0,0.6);
    }
}

.float-btn:hover {
    transform: scale(1.15) rotate(5deg);
    box-shadow: 0 6px 20px rgba(0,0,0,0.4);
}

.float-btn.phone {
    background: var(--primary-red);
}

.float-btn.zalo {
    background: #0068FF;
}

.float-btn.messenger {
    background: #0084FF;
}

/* Responsive */
@media (max-width: 1024px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .portfolio-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav {
        position: fixed;
        top: 90px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 90px);
        background: var(--white);
        flex-direction: column;
        padding: 30px;
        transition: left 0.3s ease;
        box-shadow: 0 5px 20px rgba(0,0,0,0.1);
        overflow-y: auto;
        z-index: 999;
    }
    
    .nav.active {
        left: 0;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .nav a {
        padding: 15px 0;
        border-bottom: 1px solid var(--gray);
        font-size: 1.1rem;
    }
    
    .nav a:last-child {
        border-bottom: none;
    }
    
    .nav a::before {
        display: none;
    }
    
    .nav a.active::after {
        display: none;
    }
    
    .slide-content h1 {
        font-size: 2rem;
    }
    
    .slide-content p {
        font-size: 1rem;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .services-grid,
    .features-grid,
    .portfolio-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .slide-content h1 {
        font-size: 1.5rem;
    }
    
    .cta-btn {
        padding: 12px 30px;
        font-size: 0.9rem;
    }
    
    .floating-contact {
        right: 10px;
        bottom: 10px;
    }
    
    .float-btn {
        width: 45px;
        height: 45px;
    }
}


/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--light-gray);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-red);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--dark-red);
}

/* Loading Animation */
@keyframes shimmer {
    0% {
        background-position: -1000px 0;
    }
    100% {
        background-position: 1000px 0;
    }
}

/* Button Ripple Effect */
.cta-btn, .btn-secondary, .submit-btn {
    position: relative;
    overflow: hidden;
}

.cta-btn:active, .btn-secondary:active, .submit-btn:active {
    transform: scale(0.98);
}

/* Image Zoom Effect */
.service-icon, .feature-icon, .portfolio-item, .news-image, .project-image {
    position: relative;
    overflow: hidden;
}

.service-icon::after, .feature-icon::after, .portfolio-item::after, .news-image::after, .project-image::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(139, 0, 0, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.service-card:hover .service-icon::after,
.feature:hover .feature-icon::after,
.portfolio-item:hover::after,
.news-card:hover .news-image::after,
.project-card:hover .project-image::after {
    width: 300%;
    height: 300%;
}

/* Gradient Text */
.gradient-text {
    background: linear-gradient(135deg, var(--primary-red), var(--light-red));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Card Hover Glow */
.service-card, .feature, .portfolio-item, .news-card, .project-card {
    position: relative;
}

.service-card::after, .feature::after, .news-card::after, .project-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 10px;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
    box-shadow: 0 0 30px rgba(139, 0, 0, 0.4);
}

.service-card:hover::after, .feature:hover::after, .news-card:hover::after, .project-card:hover::after {
    opacity: 1;
}

/* Smooth Page Transitions */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

section {
    animation: fadeIn 0.6s ease-out;
}

/* Enhanced Quote Style */
.quote {
    font-style: italic;
    font-size: 1.2rem;
    color: var(--dark-gray);
    margin: 20px 0;
    padding-left: 20px;
    border-left: 4px solid var(--primary-red);
    position: relative;
}

.quote::before {
    content: '"';
    position: absolute;
    left: -10px;
    top: -10px;
    font-size: 3rem;
    color: var(--primary-red);
    opacity: 0.3;
}

/* Enhanced Footer Links */
.footer a {
    color: var(--white);
    text-decoration: none;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
}

.footer a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--primary-red);
    transition: width 0.3s;
}

.footer a:hover::after {
    width: 100%;
}

/* Form Focus Effects */
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-red);
    box-shadow: 0 0 0 3px rgba(139, 0, 0, 0.1);
    transform: translateY(-2px);
}

/* Enhanced Buttons */
.submit-btn, .btn-secondary {
    position: relative;
    overflow: hidden;
}

.submit-btn::before, .btn-secondary::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.submit-btn:hover::before, .btn-secondary:hover::before {
    width: 300px;
    height: 300px;
}

/* Stats Counter Animation */
.stat-item h3 {
    font-size: 3rem;
    color: var(--primary-red);
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

/* Badge Styles */
.project-badge, .featured-badge {
    animation: slideInRight 0.5s ease;
}

@keyframes slideInRight {
    from {
        transform: translateX(100px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Enhanced Mobile Menu */
@media (max-width: 768px) {
    .nav.active {
        animation: slideInLeft 0.3s ease;
    }
    
    @keyframes slideInLeft {
        from {
            transform: translateX(-100%);
        }
        to {
            transform: translateX(0);
        }
    }
    
    .nav a {
        padding: 15px 0;
        border-bottom: 1px solid var(--gray);
        transition: all 0.3s;
    }
    
    .nav a:hover {
        padding-left: 10px;
        background: var(--light-gray);
    }
}

/* Parallax Effect for Hero */
.hero {
    background-attachment: fixed;
}

/* Enhanced Slider Dots */
.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.dot:hover {
    background: rgba(255,255,255,0.8);
    transform: scale(1.2);
}

.dot.active {
    background: var(--primary-red);
    width: 30px;
    border-radius: 6px;
    border-color: var(--white);
}

/* Print Styles */
@media print {
    .header, .floating-contact, .cta-section {
        display: none;
    }
    
    body {
        color: #000;
    }
    
    a {
        text-decoration: underline;
    }
}

/* Accessibility Improvements */
.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary-red);
    color: white;
    padding: 8px;
    text-decoration: none;
    z-index: 100;
}

.skip-to-content:focus {
    top: 0;
}

/* Focus Visible for Keyboard Navigation */
a:focus-visible, button:focus-visible {
    outline: 3px solid var(--primary-red);
    outline-offset: 2px;
}

/* Reduced Motion for Accessibility */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}