.tech-hero {
    padding: 15rem 2rem 8rem;
    background: linear-gradient(rgba(0,46,95,0.8), rgba(0,46,95,0.8)), url('../images/banner2.jpg');
    background-size: cover;
    background-position: center;
    text-align: center;
    color: #fff;
}

.tech-hero h1 {
    font-size: 4.5rem;
    margin-bottom: 2rem;
    font-weight: 700;
}

.tech-hero p {
    font-size: 2rem;
    max-width: 80rem;
    margin: 0 auto;
    opacity: 0.9;
}

/* 2. CATEGORIES & GRID */
.tech-categories {
    padding: 6rem 2rem;
}

.category-group {
    margin-bottom: 5rem;
    background: #fff;
    padding: 3rem;
    border-radius: 1.5rem;
    box-shadow: 0 0.5rem 1.5rem rgba(0,0,0,0.05);
}

.category-title {
    font-size: 2.8rem;
    color: #002e5f;
    margin-bottom: 3rem;
    border-left: 0.5rem solid #00bfff;
    padding-left: 1.5rem;
    display: flex;
    align-items: center;
}

.category-title i {
    margin-right: 1.5rem;
    color: #00bfff;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(18rem, 1fr));
    gap: 2.5rem;
}

.tech-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2.5rem;
    background: #f9f9f9;
    border-radius: 1rem;
    border: 1px solid #eee;
    transition: all .3s ease;
    text-decoration: none !important; /* Xóa gạch chân */
    outline: none !important;
}

.tech-item i {
    font-size: 4rem;
    color: #002e5f;
    margin-bottom: 1.5rem;
}

.tech-item span {
    font-size: 1.6rem;
    color: #333;
    font-weight: 600;
    
}

.tech-item:hover {
    background: #00bfff;
    transform: translateY(-0.5rem);
    border-color: #00bfff;
}

.tech-item:hover i,
.tech-item:hover span {
    color: #fff;
}
/* MOBILE RESPONSIVE */
@media (max-width: 768px) {
    .tech-hero h1 { font-size: 3.5rem; }
    .tech-grid { grid-template-columns: repeat(2, 1fr); }
}