@media (max-width:768px) {

    h2 {
        font-size: 28px;
    }

    h3 {
        font-size: 24px;
    }

    .form-select {
        height: 50px;
    }

    .btn-lg {
        font-size: 18px;
    }
}

.size-grid {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 12px;
    margin-bottom: 25px;
}

.size-btn {
    background: #111;
    border: 2px solid #444;
    color: white;
    height: 55px;
    border-radius: 12px;
    transition: .25s;
    font-weight: 600;
}

    .size-btn:hover {
        border-color: #b11226;
        transform: translateY(-2px);
    }

    .size-btn.active {
        background: #b11226;
        border-color: #b11226;
    }

@media(max-width:768px) {

    .size-grid {
        grid-template-columns: repeat(3,1fr);
    }
}