Button und Textbox auf selber Höhe

Hallo, ich hab das Problem, dass bei mir der Button versetzt zur Textbox angezeigt wird. Wie kann ich dies beheben?

Der hier verwendete Code

<style> #records{ margin-top: 123px; background-color: aquamarine; font-size: 30px; } #textbox_top{ border-style: solid; border-color: olive; border-width: 2px; font-size:30px; border-radius: 20px; padding-left: 20px; padding-right: 20px; width:70%; } .radio_button_top{ } #whole_area_top{ } #button_area{ border-radius: 20px; background-color: red; border-width: 2px; border-color: blue; color: white; height:45px; width: 20%; } #button_area:hover{ background-color: green; } #textbox_top::-webkit-input-placeholder { /* WebKit, Blink, Edge */ color: #CCCCCC; font-family: 'Grand Hotel'; font-size: 30px; font-weight: bold; } #textbox_top:-moz-placeholder { /* Mozilla Firefox 4 to 18 */ color: #CCCCCC; opacity: 1; font-family:'Grand Hotel'; font-size: 30px; font-weight: bold; } #textbox_top::-moz-placeholder { /* Mozilla Firefox 19+ */ color: #CCCCCC; opacity: 1; font-family: 'Grand Hotel'; font-size: 30px; font-weight: bold; } #textbox_top:-ms-input-placeholder { /* Internet Explorer 10-11 */ color: #CCCCCC; font-family: 'Grand Hotel'; font-size: 30px; font-weight: bold; } #textbox_top::-ms-input-placeholder { /* Microsoft Edge */ color: #CCCCCC; font-family: 'Grand Hotel'; font-size: 30px; font-weight: bold; } #textbox_top::placeholder { /* Most modern browsers support this now. */ color: #CCCCCC; font-family: 'Grand Hotel'; font-size: 30px; font-weight: bold; } label { font-size: 20px; } #helfer{ display:flex; } </style> <body> <form action="teststart.php" method="POST"> <div id="helfer"> <input type="text" id="textbox_top" name="textbox_top_php" placeholder=" Ihre Eingabe"> <button id="button_area" type="submit" >Das ist ein Button</button> </div> <label for="radio_button_top"> <input type="radio" id="titel_radio_button" class="radio_button_top" checked onclick="titel_radio_button_clicked()" name="titel_radio_button_php" value="Titel">Titel </label> <input type="radio" id="autor_radio_button" class="radio_button_top" onclick="autor_radio_button_clicked()" name="autor_radio_button_php" value="Autor">Autor </form> </body> </html>