inputタグ カスタムしてみた

<form>
	<div class="form-group">
		<label for="exampleInputEmail1">Eメールアドレス</label>
		<input type="email" class="form-control" id="exampleInputEmail1" placeholder="Eメールアドレス">
	</div>
	<div class="form-group">
		<label for="exampleInputPassword1">パスワード</label>
		<input type="password" class="form-control" id="exampleInputPassword1" placeholder="パスワード">
	</div>
	<div class="form-group">
		<label for="exampleSelect1exampleFormControlSelect1">選択の例</label>
		<select class="form-control" id="exampleFormControlSelect1">
			<option>1</option>
			<option>2</option>
			<option>3</option>
			<option>4</option>
			<option>5</option>
		</select>
	</div>
	<div class="form-group">
		<label for="exampleFormControlTextarea1">テキストエリアの例</label>
		<textarea class="form-control" id="exampleFormControlTextarea1" rows="3"></textarea>
	</div>
	<div class="form-group form-check">
		<input type="checkbox" class="form-check-input" id="exampleCheck1">
		<label class="form-check-label" for="exampleCheck1">記憶する</label>
	</div>
	<button type="submit" class="btn btn-primary">送信する</button>
</form>

/* Google Chrome, Safari, Opera 15+, Android, iOS */
input.form-control::-webkit-input-placeholder {
color: red;
}
/* Firefox 18- */
input.form-control:-moz-placeholder {
color: red;
opacity: 1;
}
/* Firefox 19+ */
input.form-control::-moz-placeholder {
color: red;
opacity: 1;
}
/* IE 10+ */
input.form-control:-ms-input-placeholder {
color: red;
}