Two Column Form

<!DOCTYPE html>
<title>My Example</title>

/* -- Start layout styles -- */
/* A container for a row that will hold columns */
.form-row {
    display: flex;
    flex-wrap: wrap; /* Allows items to wrap if needed, though we handle stacking with media queries */
    gap: 20px; /* The space between the columns */
    margin-bottom: 20px;
}
.form-row .form-group {
    flex: 1; /* Allows each form group to grow and take up equal space */
    min-width: 200px; /* Prevents columns from getting too squished before stacking */
    margin-bottom: 0;
}
/* This handles single, full-width rows */
.form-group:not(.form-row .form-group) {
    margin-bottom: 20px;
}

/* -- Responsive stacking for mobile -- */
@media (max-width: 600px) {
    .form-row {
        flex-direction: column;
        gap: 0; /* Remove gap when stacking */
    }
    .form-row .form-group {
        margin-bottom: 20px; /* Add margin back for stacked view */
    }
}
/* -- End layout styles -- */

/* General styling for labels and inputs */
.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}
.form-group input, .form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-size: 1rem;
    box-sizing: border-box;
}

.submit-btn {
    width: 100%;
    padding: 12px;
    border: none;
    background-color: #3498db;
    color: white;
    font-size: 1.1rem;
    border-radius: 5px;
    cursor: pointer;
}
</style>

<div class="two-column-form-container">
    <h2>Shipping Information</h2>
    <form action="#" method="post">
        
        <div class="form-row">
            <div class="form-group">
                <label for="first-name">First Name</label>
                <input type="text" id="first-name" name="first_name" required>
            </div>
            <div class="form-group">
                <label for="last-name">Last Name</label>
                <input type="text" id="last-name" name="last_name" required>
            </div>
        </div>

<div class="form-group">
            <label for="address">Street Address</label>
            <input type="text" id="address" name="address" required>
        </div>

<div class="form-row">
            <div class="form-group">
                <label for="city">City</label>
                <input type="text" id="city" name="city" required>
            </div>
            <div class="form-group">
                <label for="state">State / Province</label>
                <input type="text" id="state" name="state" required>
            </div>
        </div>

<div class="form-row">
            <div class="form-group">
                <label for="zip-code">Zip / Postal Code</label>
                <input type="text" id="zip-code" name="zip_code" required>
            </div>
            <div class="form-group">
                <label for="country">Country</label>
                <select id="country" name="country" required>
                    <option>United States</option>
                    <option>Canada</option>
                    <option>Mexico</option>
                </select>
            </div>
        </div>

<button type="submit" class="submit-btn">Submit</button>
    </form>
</div>