/* ===== CSS Variables ===== */
:root {
    --primary-color: #1a365d;
    --secondary-color: #2d5a87;
    --accent-color: #e6a23c;
    --accent-hover: #d4922e;
    --light-bg: #f8f9fa;
    --white: #ffffff;
    --dark: #1a202c;
    --gray: #666;
    --light-gray: #ddd;
    --shadow: 0 4px 20px rgba(0,0,0,0.1);
    --transition: all 0.3s ease;
}

/* ===== Reset ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; line-height: 1.6; color: var(--dark); background: var(--white); }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; }

/* ===== Typography ===== */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.2; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ===== Alert ===== */
.alert-success { position: fixed; top: 0; left: 0; right: 0; background: #27ae60; color: #fff; padding: 15px; text-align: center; z-index: 9999; }

/* ===== Navigation ===== */
.navbar { position: fixed; top: 0; left: 0; right: 0; background: var(--white); box-shadow: var(--shadow); z-index: 1000; height: 70px; }
.nav-container { max-width: 1200px; margin: 0 auto; padding: 0 20px; height: 100%; display: flex; align-items: center; justify-content: space-between; }
.logo { display: flex; align-items: center; gap: 10px; }
.logo-icon { width: 42px; height: 42px; background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); border-radius: 10px; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 20px; }
.logo-text { font-size: 1.5rem; font-weight: 700; color: var(--primary-color); }
.nav-menu { display: flex; align-items: center; gap: 30px; }
.nav-menu > li > a { font-weight: 500; color: var(--dark); padding: 10px 0; position: relative; }
.nav-menu > li > a::after { content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px; background: var(--accent-color); transition: var(--transition); }
.nav-menu > li > a:hover::after, .nav-menu > li > a.active::after { width: 100%; }
.nav-menu > li > a:hover { color: var(--primary-color); }
.btn-nav { background: var(--accent-color); color: #fff !important; padding: 10px 20px !important; border-radius: 6px; }
.btn-nav:hover { background: var(--accent-hover) !important; }
.dropdown { position: relative; }
.dropdown-menu { position: absolute; top: 100%; left: 0; background: #fff; box-shadow: var(--shadow); min-width: 200px; opacity: 0; visibility: hidden; transform: translateY(10px); transition: var(--transition); }
.dropdown:hover .dropdown-menu { opacity: 1; visibility: visible; transform: translateY(0); }
.dropdown-menu li a { display: block; padding: 12px 20px; color: var(--dark); }
.dropdown-menu li a:hover { background: var(--light-bg); color: var(--primary-color); }
.mobile-toggle { display: none; font-size: 24px; cursor: pointer; }

/* ===== Hero ===== */
.hero { min-height: 100vh; background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%); display: flex; align-items: center; padding-top: 70px; position: relative; }
.hero-overlay { position: absolute; inset: 0; background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>'); }
.hero-content { position: relative; z-index: 1; color: #fff; max-width: 700px; }
.hero-title { font-size: 3.5rem; margin-bottom: 20px; }
.hero-subtitle { font-size: 1.25rem; opacity: 0.9; margin-bottom: 32px; }
.hero-buttons { display: flex; gap: 16px; margin-bottom: 48px; }
.hero-buttons .btn { padding: 14px 32px; font-weight: 600; }
.btn { display: inline-block; padding: 12px 24px; border-radius: 8px; font-weight: 500; cursor: pointer; border: 2px solid transparent; transition: var(--transition); }
.btn-primary { background: var(--accent-color); color: #fff; border-color: var(--accent-color); }
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-2px); }
.btn-outline { background: transparent; color: #fff; border-color: #fff; }
.btn-outline:hover { background: #fff; color: var(--primary-color); }
.hero-stats { display: flex; gap: 48px; }
.stat { text-align: center; }
.stat-number { display: block; font-size: 2.5rem; font-weight: 700; color: var(--accent-color); }
.stat-label { font-size: 14px; opacity: 0.8; }

/* ===== Section Header ===== */
.section-header { text-align: center; margin-bottom: 50px; position: relative; }
.section-tag { display: inline-block; background: var(--primary-color); color: #fff; padding: 6px 16px; border-radius: 20px; font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 12px; }
.section-title { font-size: 2.5rem; color: var(--primary-color); margin-bottom: 16px; }
.view-all { position: absolute; right: 0; top: 50%; transform: translateY(-50%); color: var(--accent-color); font-weight: 600; }
.view-all:hover { color: var(--accent-hover); }

/* ===== Categories ===== */
.categories { padding: 100px 0; background: var(--light-bg); }
.categories-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.category-card { background: #fff; border-radius: 12px; padding: 30px; text-align: center; box-shadow: var(--shadow); transition: var(--transition); }
.category-card:hover { transform: translateY(-8px); box-shadow: 0 12px 40px rgba(0,0,0,0.15); }
.category-icon { width: 70px; height: 70px; background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 20px; font-size: 28px; color: #fff; }
.category-card h3 { font-size: 1.1rem; color: var(--primary-color); margin-bottom: 8px; }
.category-card p { color: var(--gray); font-size: 0.9rem; }

/* ===== Featured ===== */
.featured { padding: 100px 0; }
.featured-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.equipment-card { background: #fff; border-radius: 12px; overflow: hidden; box-shadow: var(--shadow); transition: var(--transition); }
.equipment-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,0.12); }
.eq-img { height: 180px; background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); display: flex; align-items: center; justify-content: center; position: relative; }
.eq-img i { font-size: 48px; color: rgba(255,255,255,0.9); }
.eq-tag { position: absolute; top: 12px; left: 12px; background: #27ae60; color: #fff; padding: 4px 12px; border-radius: 4px; font-size: 11px; font-weight: 600; }
.eq-tag.hot { background: #e74c3c; }
.eq-tag.sale { background: #f39c12; }
.eq-body { padding: 20px; }
.eq-body h4 { font-size: 16px; color: var(--primary-color); margin-bottom: 6px; }
.eq-brand { color: var(--gray); font-size: 13px; margin-bottom: 12px; }
.eq-meta { display: flex; gap: 16px; margin-bottom: 12px; font-size: 12px; color: var(--gray); }
.eq-meta span { display: flex; align-items: center; gap: 4px; }
.eq-price { border-top: 1px solid var(--light-gray); padding-top: 12px; margin-bottom: 12px; }
.price-label { display: block; font-size: 11px; color: var(--gray); }
.price-num { font-size: 18px; font-weight: 700; color: var(--accent-color); }
.btn-sm { display: block; width: 100%; padding: 10px; background: var(--primary-color); color: #fff; text-align: center; border-radius: 6px; font-size: 13px; }
.btn-sm:hover { background: var(--secondary-color); color: #fff; }

/* ===== Services ===== */
.services { padding: 100px 0; background: var(--light-bg); }
.services-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.service-card { background: #fff; border-radius: 12px; padding: 30px; text-align: center; box-shadow: var(--shadow); transition: var(--transition); }
.service-card:hover { transform: translateY(-6px); }
.service-icon { width: 70px; height: 70px; background: var(--light-bg); border-radius: 50%; display: flex; align-items: center; justify-content: center; margin: 0 auto 20px; font-size: 28px; color: var(--primary-color); }
.service-card h3 { font-size: 1.1rem; color: var(--primary-color); margin-bottom: 10px; }
.service-card p { color: var(--gray); font-size: 0.9rem; }

/* ===== Why Us ===== */
.why-us { padding: 100px 0; }
.why-us-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.why-us-features { display: flex; flex-direction: column; gap: 24px; }
.why-us-item { display: flex; gap: 16px; align-items: flex-start; }
.why-us-icon { width: 50px; height: 50px; background: var(--primary-color); border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 20px; color: #fff; flex-shrink: 0; }
.why-us-item h4 { font-size: 1rem; color: var(--primary-color); margin-bottom: 4px; }
.why-us-item p { color: var(--gray); font-size: 0.9rem; }
.why-us-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.stat-card { background: var(--light-bg); border-radius: 12px; padding: 24px; text-align: center; }
.stat-card i { font-size: 32px; color: var(--accent-color); margin-bottom: 12px; }
.stat-card .stat-number { display: block; font-size: 28px; font-weight: 700; color: var(--primary-color); }
.stat-card .stat-label { color: var(--gray); font-size: 13px; }

/* ===== Contact ===== */
.contact { padding: 100px 0; background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); }
.contact .section-tag { background: rgba(255,255,255,0.2); }
.contact .section-title { color: #fff; }
.contact-form { max-width: 600px; margin: 0 auto; background: #fff; border-radius: 16px; padding: 40px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.form-group { margin-bottom: 20px; }
.form-group input, .form-group textarea { width: 100%; padding: 14px; border: 1px solid var(--light-gray); border-radius: 8px; font-size: 15px; transition: var(--transition); }
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary-color); }
.btn-block { width: 100%; padding: 16px; font-size: 16px; }

/* ===== Footer ===== */
.footer { background: var(--dark); color: #fff; padding: 60px 0 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand p { color: #999; margin-top: 16px; font-size: 0.9rem; }
.footer-links h4 { margin-bottom: 20px; color: #fff; }
.footer-links li { margin-bottom: 12px; }
.footer-links a { color: #999; font-size: 0.9rem; }
.footer-links a:hover { color: var(--accent-color); }
.footer-contact h4 { margin-bottom: 20px; }
.footer-contact p { color: #999; font-size: 0.9rem; margin-bottom: 12px; display: flex; align-items: center; gap: 10px; }
.footer-contact i { color: var(--accent-color); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 20px; text-align: center; color: #999; font-size: 0.9rem; }
.footer-bottom a { color: #999; }
.footer-bottom a:hover { color: var(--accent-color); }

/* ===== Responsive ===== */
@media (max-width: 992px) {
    .hero-title { font-size: 2.5rem; }
    .categories-grid { grid-template-columns: repeat(2, 1fr); }
    .featured-grid { grid-template-columns: repeat(2, 1fr); }
    .services-grid { grid-template-columns: repeat(2, 1fr); }
    .why-us-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
    .nav-menu { display: none; }
    .mobile-toggle { display: block; }
    .hero-title { font-size: 2rem; }
    .hero-buttons { flex-direction: column; }
    .hero-stats { flex-wrap: wrap; gap: 24px; }
    .categories-grid, .featured-grid, .services-grid { grid-template-columns: 1fr; }
    .section-header { text-align: center; }
    .view-all { position: static; display: block; margin-top: 10px; }
    .footer-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
}

/* ===== Page Header ===== */
.page-header { background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); padding: 120px 0 60px; color: #fff; text-align: center; }
.page-header h1 { font-size: 2.5rem; margin-bottom: 10px; }
.page-header p { opacity: 0.9; }

/* ===== Breadcrumb ===== */
.breadcrumb { padding: 20px 0; background: var(--light-bg); }
.breadcrumb a { color: var(--primary-color); text-decoration: none; }
.breadcrumb span { color: #999; margin: 0 10px; }

/* ===== Categories Section ===== */
.categories-section { padding: 60px 0; background: var(--light-bg); min-height: 500px; }
.content-grid { display: grid; grid-template-columns: 250px 1fr; gap: 30px; }
.sidebar-filter { background: #fff; border-radius: 12px; padding: 25px; height: fit-content; box-shadow: var(--shadow); }
.sidebar-filter h3 { font-size: 18px; color: var(--primary-color); margin-bottom: 20px; padding-bottom: 15px; border-bottom: 1px solid var(--light-gray); }
.filter-list li { margin-bottom: 10px; }
.filter-list a { display: block; padding: 10px 15px; color: var(--dark); border-radius: 6px; transition: var(--transition); }
.filter-list a:hover, .filter-list a.active { background: var(--primary-color); color: #fff; }
.equipment-list { min-height: 400px; }

/* ===== Empty State ===== */
.empty-state { text-align: center; padding: 80px 40px; background: #fff; border-radius: 12px; }
.empty-state i { font-size: 64px; color: #ddd; margin-bottom: 20px; }
.empty-state p { color: var(--gray); margin-bottom: 20px; }

/* ===== Articles ===== */
.articles-section { padding: 60px 0; background: var(--light-bg); }
.articles-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.article-card { background: #fff; border-radius: 12px; overflow: hidden; box-shadow: var(--shadow); transition: var(--transition); text-decoration: none; display: block; }
.article-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(0,0,0,0.15); }
.article-img { height: 200px; background: linear-gradient(135deg, var(--primary-color), var(--secondary-color)); display: flex; align-items: center; justify-content: center; }
.article-img i { font-size: 48px; color: rgba(255,255,255,0.8); }
.article-body { padding: 20px; }
.article-cat { display: inline-block; background: var(--accent-color); color: #fff; padding: 4px 12px; border-radius: 4px; font-size: 11px; text-transform: uppercase; margin-bottom: 10px; }
.article-card h3 { font-size: 18px; color: var(--primary-color); margin-bottom: 10px; line-height: 1.4; }
.article-card p { color: var(--gray); font-size: 14px; line-height: 1.6; margin-bottom: 15px; }
.article-meta { color: #999; font-size: 12px; }

/* ===== Article Detail ===== */
.article-detail { padding: 60px 0; background: #fff; }
.article-content { max-width: 800px; margin: 0 auto; }
.article-header { text-align: center; margin-bottom: 40px; padding-bottom: 30px; border-bottom: 1px solid var(--light-gray); }
.article-header h1 { font-size: 2rem; color: var(--primary-color); margin-bottom: 15px; }
.article-meta { color: var(--gray); font-size: 14px; }
.article-meta i { margin-right: 5px; }
.article-body { color: var(--dark); line-height: 1.8; font-size: 16px; }
.article-body p { margin-bottom: 20px; }
.back-link { display: inline-block; margin-top: 40px; color: var(--primary-color); text-decoration: none; font-weight: 500; }
.back-link:hover { color: var(--accent-color); }

/* ===== Page Content ===== */
.page-content { padding: 60px 0; background: #fff; }
.page-body { max-width: 800px; margin: 0 auto; color: var(--dark); line-height: 1.8; font-size: 16px; }
.page-body h2 { color: var(--primary-color); margin: 30px 0 15px; }
.page-body p { margin-bottom: 15px; }
.page-body ul { margin: 15px 0; padding-left: 20px; }
.page-body li { margin-bottom: 10px; }

/* ===== Responsive ===== */
@media (max-width: 992px) {
    .content-grid { grid-template-columns: 1fr; }
    .sidebar-filter { display: none; }
    .articles-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    .articles-grid { grid-template-columns: 1fr; }
}