:root {
    --primary-color: #003366;
    --secondary-color: #008080;
    --accent-color: #FF9900;
    --text-color: #333333;
    --light-text: #666666;
    --bg-light: #F4F7F6;
    --white: #FFFFFF;
    --glass-bg: rgba(255, 255, 255, 0.8);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--white);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

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

/* Header */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
    letter-spacing: -1px;
}

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

.nav-links a {
    font-weight: 500;
    font-size: 0.95rem;
}

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

/* Hero Section */
.hero {
    height: 70vh;
    background: linear-gradient(rgba(0, 51, 102, 0.6), rgba(0, 51, 102, 0.6)), url('../images/hero_bg.jpg') no-repeat center center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding-top: 80px;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-content p {
    font-size: 1.25rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent-color);
    color: var(--white);
    border-radius: 5px;
    font-weight: 600;
    transition: var(--transition);
}

.btn:hover {
    background-color: #e68a00;
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(255, 153, 0, 0.3);
}

/* Section Common */
section {
    padding: 100px 0;
}

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

.section-title h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.section-title .underline {
    width: 60px;
    height: 4px;
    background-color: var(--secondary-color);
    margin: 0 auto;
}

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

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 60px;
    align-items: center;
}

.about-img img {
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.about-text h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--primary-color);
}

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

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

.advantage-card {
    padding: 40px;
    background: var(--white);
    border-radius: 15px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.advantage-card:hover {
    transform: translateY(-10px);
}

.advantage-card i {
    font-size: 3rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
    display: block;
}

.advantage-card h3 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

/* Products */
.products {
    background-color: var(--bg-light);
}

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

.product-card {
    position: relative;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.product-card img {
    width: 100%;
    height: 400px;
    object-fit: cover;
    transition: var(--transition);
}

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

.product-info {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 30px;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.8));
    color: var(--white);
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1.5fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-logo {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 20px;
}

.footer-info p {
    opacity: 0.7;
    margin-bottom: 10px;
}

.footer-links h4,
.footer-contact h4 {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

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

.footer-links ul li a {
    opacity: 0.7;
}

.footer-links ul li a:hover {
    opacity: 1;
    padding-left: 5px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    opacity: 0.5;
}

/* Responsive */
@media (max-width: 992px) {

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

    .hero-content h1 {
        font-size: 2.5rem;
    }
}

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

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

    section {
        padding: 60px 0;
    }
}