grid input bootstrap code example

Example 1: large input box bootstrap 4

.form-control-sm
.form-control-lg

Example 2: bootstrap form-control inline

<div class="form-group">
    <label for="birthday" class="col-xs-2 control-label">Birthday</label>
    <div class="col-xs-10">
        <div class="form-inline">
            <div class="form-group">
                <input type="text" class="form-control" placeholder="year"/>
            </div>
            <div class="form-group">
                <input type="text" class="form-control" placeholder="month"/>
            </div>
            <div class="form-group">
                <input type="text" class="form-control" placeholder="day"/>
            </div>
        </div>
    </div>
</div>