:root {
    --primary-color: #f39c12;
    --dark-color: #2c3e50;
    --light-bg: #f8f9fa;
}

body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--light-bg);
    color: #333;
}

.container { width: 90%; max-width: 1200px; margin: 0 auto; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }

/* Header Modern */
.header { background: #fff; padding: 15px 0; box-shadow: 0 2px 10px rgba(0,0,0,0.05); position: sticky; top: 0; z-index: 100;}
.nav-menu ul { list-style: none; display: flex; gap: 20px; }
.nav-menu a { text-decoration: none; color: var(--dark-color); font-weight: 600; text-transform: uppercase; font-size: 14px; transition: 0.3s;}
.nav-menu a:hover, .nav-menu a.active { color: var(--primary-color); }

/* Hero Banner */
.hero {
    height: 60vh;
    background: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('../images/banner.jpg') center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #fff;
}
.hero h1 { font-size: 3rem; margin-bottom: 10px; }

/* Grid Cards (Sản phẩm) */
.section-title { text-align: center; margin: 50px 0 30px; font-size: 2rem; color: var(--dark-color); }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; margin-bottom: 50px;}

.card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s ease;
}
.card:hover { transform: translateY(-5px); }
.card img { width: 100%; height: 200px; object-fit: cover; }
.card-content { padding: 20px; }
.card-content h3 { margin-top: 0; font-size: 18px; }
.btn { display: inline-block; padding: 10px 20px; background: var(--primary-color); color: #fff; text-decoration: none; border-radius: 5px; font-weight: bold; }
/* --- TỐI ƯU MOBILE CHO TRANG FRONT-END --- */
.mobile-menu-btn { display: none; font-size: 28px; background: none; border: none; color: var(--dark-color); cursor: pointer; padding: 5px; }

@media (max-width: 768px) {
    .header { position: relative; padding: 10px 0;}
    .mobile-menu-btn { display: block; } /* Hiện nút 3 gạch */
    
    /* Chuyển menu ngang thành menu dọc xổ xuống */
    .nav-menu { display: none; position: absolute; top: 100%; left: 0; width: 100%; background: #fff; box-shadow: 0 10px 10px rgba(0,0,0,0.1); z-index: 100; border-top: 1px solid #eee;}
    .nav-menu.active { display: block; }
    .nav-menu ul { flex-direction: column; gap: 0; padding: 0; margin: 0; }
    .nav-menu ul li { border-bottom: 1px solid #f8f9fa; }
    .nav-menu a { display: block; padding: 15px 20px; text-align: left; }
    
    /* Nhỏ chữ Slider */
    .swiper { height: 40vh; }
    .slide-caption { font-size: 16px; padding: 10px 15px; bottom: 20px;}
    
    /* Lưới bài viết thành 1 cột */
    .grid-3 { grid-template-columns: 1fr; gap: 20px; }
}