/*
Theme Name: Tu Van Cuu Long
Author: Tu Bui
Description: 
Version: 3.0
*/

:root {
    --primary: #004a8c; /* Xanh đậm Opacontrol */
    --accent: #76df19;  /* Vàng thương hiệu */
    --hover: #e6b800;
}

body { font-family: 'Roboto', Arial, sans-serif; margin: 0; padding: 0; color: #333; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 15px; }

/* TOPBAR */
.top-bar { background: #f8f8f8; padding: 8px 0; font-size: 13px; border-bottom: 1px solid #eee; }
.top-flex { display: flex; justify-content: space-between; align-items: center; }

/* HEADER */
header { background: var(--primary); color: #fff; }
.header-main { display: flex; justify-content: space-between; align-items: center; padding: 10px 0; }
.logo img { height: 70px; display: block; }

/* MENU */
nav ul { list-style: none; display: flex; margin: 0; padding: 0; }
nav ul li a { 
    color: #fff; text-decoration: none; padding: 25px 15px; 
    display: block; font-weight: bold; text-transform: uppercase; font-size: 14px; 
}
nav ul li a:hover { color: var(--accent); background: rgba(0,0,0,0.1); }
.nav-border { height: 4px; background: #0e228f; width: 100%; }

/* HERO SLIDER */
.hero { 
    background: url('https://opacontrol.com.vn/uploads/images/slider/slider-1.jpg') no-repeat center center; 
    background-size: cover; height: 550px; position: relative;
}
.hero-overlay { 
    position: absolute; top: 0; left: 0; width: 100%; height: 100%; 
    background: linear-gradient(to right, rgba(0,74,140,0.8) 30%, transparent); 
}
.hero-content { position: relative; color: #fff; padding-top: 120px; max-width: 600px; }
.hero h1 { font-size: 40px; text-transform: uppercase; line-height: 1.2; }
.btn-more { 
    background: var(--accent); color: #000; padding: 12px 30px; 
    text-decoration: none; font-weight: bold; border-radius: 4px; display: inline-block;
}

/* DỊCH VỤ GRID */
.services { padding: 60px 0; background: #fff; }
.section-title { text-align: center; color: var(--primary); margin-bottom: 40px; text-transform: uppercase; }
.service-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.service-card { 
    border: 1px solid #eee; padding: 20px; text-align: center; 
    transition: 0.4s; position: relative; overflow: hidden;
}
.service-card:hover { border-bottom: 4px solid var(--primary); transform: translateY(-5px); box-shadow: 0 10px 30px rgba(0,0,0,0.1); }
.service-card h3 { font-size: 16px; margin: 15px 0; min-height: 45px; }

/* FOOTER */
footer { background: #1a1a1a; color: #fff; padding: 50px 0; margin-top: 50px; }
.footer-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 50px; }
.footer-col h4 { border-left: 4px solid var(--accent); padding-left: 10px; text-transform: uppercase; }