function validateForm() {
    var input = document.getElementById('queryInput');
    if (input.value.trim() === "") {
        input.placeholder = "type in your query";
        input.classList.add('center-placeholder');
        return false; // Prevent form submission
    }
    input.classList.remove('center-placeholder'); // default text is left-aligned if not empty
    return true; // Allow form submission
}

function clearPlaceholder() {
    var input = document.getElementById('queryInput');
    if (input.placeholder === "type in your query") {
        input.placeholder = "";
        input.classList.remove('center-placeholder'); // Remove the centering class
    }
}