/* ========================================
   PROJECT FILTER BUTTONS FIX
   CSS cho filter buttons và z-index fix
   ======================================== */

/* Ensure all sections are above background */
section {
    position: relative;
    z-index: 10;
    padding: 100px 0;
}

/* Projects Filter Buttons */
.projects-filter {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin: 40px 0;
    flex-wrap: wrap;
    position: relative;
    z-index: 100;
}

.filter-btn {
    padding: 12px 28px;
    background: rgba(17, 34, 64, 0.6);
    border: 2px solid rgba(0, 212, 255, 0.3);
    border-radius: 50px;
    color: #E6F1FF;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer !important;
    transition: all 0.3s ease;
    position: relative;
    z-index: 100;
    backdrop-filter: blur(10px);
    pointer-events: auto !important;
    user-select: none;
}

.filter-btn:hover {
    background: rgba(0, 102, 255, 0.2);
    border-color: rgba(0, 212, 255, 0.6);
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0, 102, 255, 0.3);
}

.filter-btn.active {
    background: linear-gradient(135deg, #0066FF, #00D4FF);
    border-color: transparent;
    color: white;
    box-shadow: 0 5px 25px rgba(0, 102, 255, 0.5);
}

.filter-btn.active:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 102, 255, 0.6);
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    margin-top: 40px;
    position: relative;
    z-index: 15;
}

.project-card {
    position: relative;
    z-index: 15;
    opacity: 1;
    transform: scale(1);
    transition: all 0.3s ease;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .projects-filter {
        gap: 10px;
    }

    .filter-btn {
        padding: 10px 20px;
        font-size: 13px;
    }

    .projects-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
}