.certificate-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
    width: 100%;
}

.certificate-list li {
    background: var(--color-card-bg);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 4px 16px rgba(26,35,126,0.10);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
    width: 100%;
    max-width: 100%;
    box-sizing: border-box;
}

.certificate-list li:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 32px rgba(26,35,126,0.15);
}

.certificate-list img {
    width: 100%;
    height: auto;
    border-radius: 12px;
    margin-bottom: 1rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.certificate-list p {
    color: var(--color-highlight);
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0;
    text-align: center;
}

/* Modal for full-size certificate viewing */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.8);
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    max-width: 90%;
    max-height: 90%;
}

.modal-content img {
    width: 100%;
    height: auto;
    border-radius: 8px;
}

.close {
    position: absolute;
    top: 10px;
    right: 25px;
    color: white;
    font-size: 35px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: #ccc;
}

/* Mobile and Tablet Responsive Design */
@media (max-width: 900px) {
    .certificate-list {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 1.5rem;
    }
}

@media (max-width: 768px) {
    .certificate-list {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        margin-top: 1.5rem;
    }
    
    .certificate-list li {
        padding: 1.2rem;
        border-radius: 12px;
    }
    
    .certificate-list img {
        border-radius: 8px;
        margin-bottom: 0.8rem;
    }
    
    .certificate-list p {
        font-size: 1.1rem;
    }
    
    .modal-content {
        max-width: 95%;
        max-height: 95%;
    }
    
    .close {
        top: 5px;
        right: 15px;
        font-size: 30px;
    }
}

@media (max-width: 480px) {
    .certificate-list {
        gap: 1rem;
        margin-top: 1rem;
        padding: 0 0.5rem;
    }
    
    .certificate-list li {
        padding: 1rem;
        border-radius: 10px;
    }
    
    .certificate-list img {
        border-radius: 6px;
        margin-bottom: 0.6rem;
    }
    
    .certificate-list p {
        font-size: 1rem;
        line-height: 1.4;
    }
    
    .modal-content {
        max-width: 98%;
        max-height: 98%;
    }
    
    .close {
        top: 2px;
        right: 10px;
        font-size: 28px;
    }
}

@media (max-width: 360px) {
    .certificate-list {
        padding: 0 0.2rem;
    }
    
    .certificate-list li {
        padding: 0.8rem;
    }
    
    .certificate-list p {
        font-size: 0.95rem;
    }
    
    .close {
        font-size: 25px;
        right: 8px;
    }
}