How to make element stretch vertically and not affect look?

Question

I have a page that looks like this.

//$(document).ready(function() {

//   function viewport_height() {
//      var window_height = $(window).height();
//      $('#wrapper').height(window_height);
//      $('#chat-area').height = $(window_height);
      
//   }

//   viewport_height();

//   $(window).resize(function() {
//      viewport_height();
//  });

//});

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  text-decoration: none;
  font-family: 'Poppins', sans-serif;
}
body{
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: #f7f7f7;
  padding: 0 10px;
}
.wrapper{
  background: #fff;
  max-width: 450px;
  width: 100%;
  border-radius: 16px;
  box-shadow:
  0 0 128px 0 rgba(0, 0, 0, 0.1),
              0 32px 64px -48px rgba(0, 0, 0, 0.5);
}

/* Login & Signup Form CSS Start */
.form{
  padding: 25px 30px;
}
.form header{
  font-size: 25px;
  font-weight: 600;
  padding-bottom: 10px;
  border-bottom: 1px solid #e6e6e6;
}
.form form{
  margin: 20px 0;
}
.form form .error-text{
  color: #721c24;
  padding: 8px 10px;
  text-align: center;
  border-radius: 5px;
  background: #f8d7da;
  border: 1px solid #f5c6cb;
  margin-bottom: 10px;
  display: none;
}
.form form .name-details{
  display: flex;
}
.form .name-details .field:first-child{
  margin-right: 10px;
}
.form .name-details .field:last-child{
  margin-left: 10px;
}
.form form .field{
  display: flex;
  margin-bottom: 10px;
  flex-direction: column;
  position: relative;
}
.form form .field label{
  margin-bottom: 2px;
}
.form form .input input{
  height: 40px;
  width: 100%;
  font-size: 16px;
  padding: 0 10px;
  border-radius: 5px;
  border: 1px solid #ccc;
}
.form form .field input{
  outline: none;
}
.form form .image input{
  font-size: 17px;
}
.form form .button input{
  height: 45px;
  border: none;
  color: #fff;
  font-size: 17px;
  background: #333;
  border-radius: 5px;
  cursor: pointer;
  margin-top: 13px;
}
.form form .field i{
  position: absolute;
  right: 15px;
  top: 70%;
  color: #ccc;
  cursor: pointer;
  transform: translateY(-50%);
}
.form form .field i.active::before{
  color: #333;
  content: "\f070";
}
.form .link{
  text-align: center;
  margin: 10px 0;
  font-size: 17px;
}
.form .link a{
  color: #333;
}
.form .link a:hover{
  text-decoration: underline;
}


/* Users List CSS Start */
.users{
  padding: 25px 30px;
}
.users header,
.users-list a{
  display: flex;
  align-items: center;
  padding-bottom: 20px;
  border-bottom: 1px solid #e6e6e6;
  justify-content: space-between;
}
.wrapper img{
  object-fit: cover;
  border-radius: 50%;
}
.users header img{
  height: 50px;
  width: 50px;
}
:is(.users, .users-list) .content{
  display: flex;
  align-items: center;
}
:is(.users, .users-list) .content .details{
  color: #000;
  margin-left: 20px;
}
:is(.users, .users-list) .details span{
  font-size: 18px;
  font-weight: 500;
}
.users header .logout{
  display: block;
  background: #333;
  color: #fff;
  outline: none;
  border: none;
  padding: 7px 15px;
  text-decoration: none;
  border-radius: 5px;
  font-size: 17px;
}
.users .search{
  margin: 20px 0;
  display: flex;
  position: relative;
  align-items: center;
  justify-content: space-between;
}
.users .search .text{
  font-size: 18px;
}
.users .search input{
  position: absolute;
  height: 42px;
  width: calc(100% - 50px);
  font-size: 16px;
  padding: 0 13px;
  border: 1px solid #e6e6e6;
  outline: none;
  border-radius: 5px 0 0 5px;
  opacity: 0;
  pointer-events: none;
  transition: all 0.2s ease;
}
.users .search input.show{
  opacity: 1;
  pointer-events: auto;
}
.users .search button{
  position: relative;
  z-index: 1;
  width: 47px;
  height: 42px;
  font-size: 17px;
  cursor: pointer;
  border: none;
  background: #fff;
  color: #333;
  outline: none;
  border-radius: 0 5px 5px 0;
  transition: all 0.2s ease;
}
.users .search button.active{
  background: #333;
  color: #fff;
}
.search button.active i::before{
  content: '\f00d';
}
.users-list{
  max-height: 350px;
  overflow-y: auto;
}
:is(.users-list, .chat-box)::-webkit-scrollbar{
  width: 0px;
}
.users-list a{
  padding-bottom: 10px;
  margin-bottom: 15px;
  padding-right: 15px;
  border-bottom-color: #f1f1f1;
}
.users-list a:last-child{
  margin-bottom: 0px;
  border-bottom: none;
}
.users-list a img{
  height: 40px;
  width: 40px;
}
.users-list a .details p{
  color: #67676a;
}
.users-list a .status-dot{
  font-size: 12px;
  color: #468669;
  padding-left: 10px;
}
.users-list a .status-dot.offline{
  color: #ccc;
}

/* Chat Area CSS Start */
.chat-area header{
  display: flex;
  align-items: center;
  padding: 18px 30px;
}
.chat-area header .back-icon{
  color: #333;
  font-size: 18px;
}
.chat-area header img{
  height: 45px;
  width: 45px;
  margin: 0 15px;
}
.chat-area header .details span{
  font-size: 17px;
  font-weight: 500;
}
.chat-box{
  position: relative;
  min-height: 500px;
  max-height: 500px;
  overflow-y: auto;
  padding: 10px 30px 20px 30px;
  background: #f7f7f7;
  box-shadow: inset 0 32px 32px -32px rgb(0 0 0 / 5%),
              inset 0 -32px 32px -32px rgb(0 0 0 / 5%);
}
.chat-box .text{
  position: absolute;
  top: 45%;
  left: 50%;
  width: calc(100% - 50px);
  text-align: center;
  transform: translate(-50%, -50%);
}
.chat-box .chat{
  margin: 15px 0;
}
.chat-box .chat p{
  word-wrap: break-word;
  padding: 8px 16px;
  box-shadow: 0 0 32px rgb(0 0 0 / 8%),
              0rem 16px 16px -16px rgb(0 0 0 / 10%);
}
.chat-box .outgoing{
  display: flex;
}
.chat-box .outgoing .details{
  margin-left: auto;
  max-width: calc(100% - 130px);
}
.outgoing .details p{
  background: #333;
  color: #fff;
  border-radius: 18px 18px 0 18px;
}
.chat-box .incoming{
  display: flex;
  align-items: flex-end;
}
.chat-box .incoming img{
  height: 35px;
  width: 35px;
}
.chat-box .incoming .details{
  margin-right: auto;
  margin-left: 10px;
  max-width: calc(100% - 130px);
}
.incoming .details p{
  background: #fff;
  color: #333;
  border-radius: 18px 18px 18px 0;
}
.typing-area{
  padding: 18px 30px;
  display: flex;
  justify-content: space-between;
}
.typing-area input{
  height: 45px;
  width: calc(100% - 58px);
  font-size: 16px;
  padding: 0 13px;
  border: 1px solid #e6e6e6;
  outline: none;
  border-radius: 5px 0 0 5px;
}
.typing-area button{
  color: #fff;
  width: 55px;
  border: none;
  outline: none;
  background: #333;
  font-size: 19px;
  cursor: pointer;
  opacity: 0.7;
  pointer-events: none;
  border-radius: 0 5px 5px 0;
  transition: all 0.3s ease;
}
.typing-area button.active{
  opacity: 1;
  pointer-events: auto;
}

/* Responive media query */
@media screen and (max-width: 450px) {
  .form, .users{
    padding: 20px;
  }
  .form header{
    text-align: center;
  }
  .form form .name-details{
    flex-direction: column;
  }
  .form .name-details .field:first-child{
    margin-right: 0px;
  }
  .form .name-details .field:last-child{
    margin-left: 0px;
  }

  .users header img{
    height: 45px;
    width: 45px;
  }
  .users header .logout{
    padding: 6px 10px;
    font-size: 16px;
  }
  :is(.users, .users-list) .content .details{
    margin-left: 15px;
  }

  .users-list a{
    padding-right: 10px;
  }

  .chat-area header{
    padding: 15px 20px;
  }
  .chat-box{
    min-height: 400px;
    padding: 10px 15px 15px 20px;
  }
  .chat-box .chat p{
    font-size: 15px;
  }
  .chat-box .outogoing .details{
    max-width: 230px;
  }
  .chat-box .incoming .details{
    max-width: 265px;
  }
  .incoming .details img{
    height: 30px;
    width: 30px;
  }
  .chat-area form{
    padding: 20px;
  }
  .chat-area form input{
    height: 40px;
    width: calc(100% - 48px);
  }
  .chat-area form button{
    width: 45px;
  }
}

<html lang="en"><head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>My Online Chat App | Hello World</title>
  <link rel="stylesheet" href="style.css">
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.2/css/all.min.css">
</head><body>
<!--<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>-->
  <div class="wrapper" id="wrapper">
    <section class="chat-area" id="chat-area">
      <header>
        <div class="details">
          <span>User</span>
          <p>Active now</p>
        </div>
      </header>
      <div class="chat-box">
      <div class="chat incoming">
      <div class="details">
      <p>j</p>
      </div>
      </div>
      <div class="chat incoming">
      <div class="details">
      <p>j</p>
      </div>
      </div>
      <div class="chat incoming">
      <div class="details">
        <p>j</p>
        </div>
        </div><div class="chat incoming">
        <div class="details">
          <p>j</p>
        </div>
        </div><div class="chat incoming">
        <div class="details">
          <p>j</p>
        </div>
        </div><div class="chat incoming">
        <div class="details">
          <p>j</p>
        </div>
        </div><div class="chat incoming">
        <div class="details">
          <p>j</p>
        </div>
        </div><div class="chat outgoing">
        <div class="details">
          <p>tst</p>
        </div>
        </div><div class="chat outgoing">
        <div class="details">
          <p>test</p>
        </div>
        </div><div class="chat outgoing">
        <div class="details">
          <p>test</p>
        </div>
        </div></div>
      <form action="#" class="typing-area">
        <input type="text" class="incoming_id" name="incoming_id" value="340930066" hidden="">
        <input type="text" name="message" class="input-field" placeholder="Type a message here..." autocomplete="off">
        <button><i class="fab fa-telegram-plane"></i></button>
      </form>
    </section>
  </div>
  </body></html>

I want the <div class="wrapper"> to resize vertically when height of the device doesn't fit. So when I shrink my browser to a smaller height it will look shrink with it. Also I want the look to stay. I tried to do display: flex; but it just made everything go everywhere. I can't seem to do it. I am trying to do it with JavaScript, but it doesn't work the way it should. Changing the viewport height does not help.

I know your tags say `html` and `css` .. So I am mentioning this in a comment .. I have done this many times and the easiest way is using a JavaScript listener to watch for display resize amongst what ever you want to listen for (in addition to running the resize function once on document ready). It grabs the display (view port) height in pixels and sets the wrapper's height accordingly. — Zak, Apr 09 '21 at 17:43
Ok. How can I do that? Can I get a link to a question answers that? — , Apr 09 '21 at 17:45
https://stackoverflow.com/questions/19193801/how-to-resize-a-div-to-clients-viewport-height -- There is a jQuery answer toward the end that should get you started .. — Zak, Apr 09 '21 at 17:46
@Zak can you look at my jsfiddle and tell my how that will help. — , Apr 09 '21 at 17:51
I suspect that JS is unneeded here and this can be accomplished with flex-- I'm looking right now... — Alexander Nied, Apr 09 '21 at 17:54
Your description is a bit confusing, do you want the header/footer to stay in place and the body to shrink/grow when height changes? if so then you can easily do this with flex, no js needed — Huangism, Apr 09 '21 at 18:51
@j08691 The reason I have all the code is because I have no idea what is preventing me from doing this. — , Apr 09 '21 at 18:51

score 2 · Accepted Answer · answered Apr 09 '21 at 18:57

Is this what you are looking for? I wasn't 100% sure from the description

The only css I added are at the bottom of the css section

.chat-area {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}
.chat-area header,
.chat-area typing-area {
  flex-shrink: 0;
}
.chat-box {
  flex-grow: 1;
  min-height: auto;
}

The above is the only css I added, the min-height: auto; was to override your original code. Original code is not modified

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  text-decoration: none;
  font-family: 'Poppins', sans-serif;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: #f7f7f7;
  padding: 0 10px;
}

.wrapper {
  background: #fff;
  max-width: 450px;
  width: 100%;
  border-radius: 16px;
  box-shadow: 0 0 128px 0 rgba(0, 0, 0, 0.1), 0 32px 64px -48px rgba(0, 0, 0, 0.5);
}


/* Login & Signup Form CSS Start */

.form {
  padding: 25px 30px;
}

.form header {
  font-size: 25px;
  font-weight: 600;
  padding-bottom: 10px;
  border-bottom: 1px solid #e6e6e6;
}

.form form {
  margin: 20px 0;
}

.form form .error-text {
  color: #721c24;
  padding: 8px 10px;
  text-align: center;
  border-radius: 5px;
  background: #f8d7da;
  border: 1px solid #f5c6cb;
  margin-bottom: 10px;
  display: none;
}

.form form .name-details {
  display: flex;
}

.form .name-details .field:first-child {
  margin-right: 10px;
}

.form .name-details .field:last-child {
  margin-left: 10px;
}

.form form .field {
  display: flex;
  margin-bottom: 10px;
  flex-direction: column;
  position: relative;
}

.form form .field label {
  margin-bottom: 2px;
}

.form form .input input {
  height: 40px;
  width: 100%;
  font-size: 16px;
  padding: 0 10px;
  border-radius: 5px;
  border: 1px solid #ccc;
}

.form form .field input {
  outline: none;
}

.form form .image input {
  font-size: 17px;
}

.form form .button input {
  height: 45px;
  border: none;
  color: #fff;
  font-size: 17px;
  background: #333;
  border-radius: 5px;
  cursor: pointer;
  margin-top: 13px;
}

.form form .field i {
  position: absolute;
  right: 15px;
  top: 70%;
  color: #ccc;
  cursor: pointer;
  transform: translateY(-50%);
}

.form form .field i.active::before {
  color: #333;
  content: "\f070";
}

.form .link {
  text-align: center;
  margin: 10px 0;
  font-size: 17px;
}

.form .link a {
  color: #333;
}

.form .link a:hover {
  text-decoration: underline;
}


/* Users List CSS Start */

.users {
  padding: 25px 30px;
}

.users header,
.users-list a {
  display: flex;
  align-items: center;
  padding-bottom: 20px;
  border-bottom: 1px solid #e6e6e6;
  justify-content: space-between;
}

.wrapper img {
  object-fit: cover;
  border-radius: 50%;
}

.users header img {
  height: 50px;
  width: 50px;
}

:is(.users,
.users-list) .content {
  display: flex;
  align-items: center;
}

:is(.users,
.users-list) .content .details {
  color: #000;
  margin-left: 20px;
}

:is(.users,
.users-list) .details span {
  font-size: 18px;
  font-weight: 500;
}

.users header .logout {
  display: block;
  background: #333;
  color: #fff;
  outline: none;
  border: none;
  padding: 7px 15px;
  text-decoration: none;
  border-radius: 5px;
  font-size: 17px;
}

.users .search {
  margin: 20px 0;
  display: flex;
  position: relative;
  align-items: center;
  justify-content: space-between;
}

.users .search .text {
  font-size: 18px;
}

.users .search input {
  position: absolute;
  height: 42px;
  width: calc(100% - 50px);
  font-size: 16px;
  padding: 0 13px;
  border: 1px solid #e6e6e6;
  outline: none;
  border-radius: 5px 0 0 5px;
  opacity: 0;
  pointer-events: none;
  transition: all 0.2s ease;
}

.users .search input.show {
  opacity: 1;
  pointer-events: auto;
}

.users .search button {
  position: relative;
  z-index: 1;
  width: 47px;
  height: 42px;
  font-size: 17px;
  cursor: pointer;
  border: none;
  background: #fff;
  color: #333;
  outline: none;
  border-radius: 0 5px 5px 0;
  transition: all 0.2s ease;
}

.users .search button.active {
  background: #333;
  color: #fff;
}

.search button.active i::before {
  content: '\f00d';
}

.users-list {
  max-height: 350px;
  overflow-y: auto;
}

:is(.users-list,
.chat-box)::-webkit-scrollbar {
  width: 0px;
}

.users-list a {
  padding-bottom: 10px;
  margin-bottom: 15px;
  padding-right: 15px;
  border-bottom-color: #f1f1f1;
}

.users-list a:last-child {
  margin-bottom: 0px;
  border-bottom: none;
}

.users-list a img {
  height: 40px;
  width: 40px;
}

.users-list a .details p {
  color: #67676a;
}

.users-list a .status-dot {
  font-size: 12px;
  color: #468669;
  padding-left: 10px;
}

.users-list a .status-dot.offline {
  color: #ccc;
}


/* Chat Area CSS Start */

.chat-area header {
  display: flex;
  align-items: center;
  padding: 18px 30px;
}

.chat-area header .back-icon {
  color: #333;
  font-size: 18px;
}

.chat-area header img {
  height: 45px;
  width: 45px;
  margin: 0 15px;
}

.chat-area header .details span {
  font-size: 17px;
  font-weight: 500;
}

.chat-box {
  position: relative;
  min-height: 500px;
  max-height: 500px;
  overflow-y: auto;
  padding: 10px 30px 20px 30px;
  background: #f7f7f7;
  box-shadow: inset 0 32px 32px -32px rgb(0 0 0 / 5%), inset 0 -32px 32px -32px rgb(0 0 0 / 5%);
}

.chat-box .text {
  position: absolute;
  top: 45%;
  left: 50%;
  width: calc(100% - 50px);
  text-align: center;
  transform: translate(-50%, -50%);
}

.chat-box .chat {
  margin: 15px 0;
}

.chat-box .chat p {
  word-wrap: break-word;
  padding: 8px 16px;
  box-shadow: 0 0 32px rgb(0 0 0 / 8%), 0rem 16px 16px -16px rgb(0 0 0 / 10%);
}

.chat-box .outgoing {
  display: flex;
}

.chat-box .outgoing .details {
  margin-left: auto;
  max-width: calc(100% - 130px);
}

.outgoing .details p {
  background: #333;
  color: #fff;
  border-radius: 18px 18px 0 18px;
}

.chat-box .incoming {
  display: flex;
  align-items: flex-end;
}

.chat-box .incoming img {
  height: 35px;
  width: 35px;
}

.chat-box .incoming .details {
  margin-right: auto;
  margin-left: 10px;
  max-width: calc(100% - 130px);
}

.incoming .details p {
  background: #fff;
  color: #333;
  border-radius: 18px 18px 18px 0;
}

.typing-area {
  padding: 18px 30px;
  display: flex;
  justify-content: space-between;
}

.typing-area input {
  height: 45px;
  width: calc(100% - 58px);
  font-size: 16px;
  padding: 0 13px;
  border: 1px solid #e6e6e6;
  outline: none;
  border-radius: 5px 0 0 5px;
}

.typing-area button {
  color: #fff;
  width: 55px;
  border: none;
  outline: none;
  background: #333;
  font-size: 19px;
  cursor: pointer;
  opacity: 0.7;
  pointer-events: none;
  border-radius: 0 5px 5px 0;
  transition: all 0.3s ease;
}

.typing-area button.active {
  opacity: 1;
  pointer-events: auto;
}


/* Responive media query */

@media screen and (max-width: 450px) {
  .form,
  .users {
    padding: 20px;
  }
  .form header {
    text-align: center;
  }
  .form form .name-details {
    flex-direction: column;
  }
  .form .name-details .field:first-child {
    margin-right: 0px;
  }
  .form .name-details .field:last-child {
    margin-left: 0px;
  }
  .users header img {
    height: 45px;
    width: 45px;
  }
  .users header .logout {
    padding: 6px 10px;
    font-size: 16px;
  }
   :is(.users,
  .users-list) .content .details {
    margin-left: 15px;
  }
  .users-list a {
    padding-right: 10px;
  }
  .chat-area header {
    padding: 15px 20px;
  }
  .chat-box {
    min-height: 400px;
    padding: 10px 15px 15px 20px;
  }
  .chat-box .chat p {
    font-size: 15px;
  }
  .chat-box .outogoing .details {
    max-width: 230px;
  }
  .chat-box .incoming .details {
    max-width: 265px;
  }
  .incoming .details img {
    height: 30px;
    width: 30px;
  }
  .chat-area form {
    padding: 20px;
  }
  .chat-area form input {
    height: 40px;
    width: calc(100% - 48px);
  }
  .chat-area form button {
    width: 45px;
  }
}

.chat-area {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

.chat-area header,
.chat-area typing-area {
  flex-shrink: 0;
}

.chat-box {
  flex-grow: 1;
  min-height: auto;
}

<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>My Online Chat App | Hello World</title>
  <link rel="stylesheet" href="style.css">
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.2/css/all.min.css">
</head>

<body>
  <input id="hidden" type="hidden" value="7">
  <div class="wrapper">
    <section class="chat-area">
      <header>
        <a href="users.php" class="back-icon"><i class="fas fa-arrow-left"></i></a>
        <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
        <div class="details">
          <span>Justin Skinner</span>
          <p>Active now</p>
        </div>
      </header>
      <div class="chat-box">
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat incoming">
          <img src="https://sign-up-hello-world.000webhostapp.com/ChatApp/php/images/1617736821tigeer.jpg" alt="">
          <div class="details">
            <p>j</p>
          </div>
        </div>
        <div class="chat outgoing">
          <div class="details">
            <p>tst</p>
          </div>
        </div>
        <div class="chat outgoing">
          <div class="details">
            <p>test</p>
          </div>
        </div>
        <div class="chat outgoing">
          <div class="details">
            <p>test</p>
          </div>
        </div>
      </div>
      <form action="#" class="typing-area">
        <input type="text" class="incoming_id" name="incoming_id" value="340930066" hidden="">
        <input type="text" name="message" class="input-field" placeholder="Type a message here..." autocomplete="off">
        <button><i class="fab fa-telegram-plane"></i></button>
      </form>
    </section>
  </div>

  <script src="javascript/chat.js"></script>
</body>

</html>

The key is flex container need to have the height and the overflow hidden and your middle body needs to have flex grow. — Huangism, Apr 09 '21 at 19:01

score 2 · Answer 2 · answered Apr 09 '21 at 19:00

Here's how to do it with flexbox using this answer.

JSFiddle

body{
  height:100vh
}

.wrapper{
  height:100%;
}

.chat-area{
  display: flex; /* displays flex-items (children) inline */
  flex-direction: column; /* stacks them vertically */
  height: 100%; /* needs to take the parents height, alternative: body {display: flex} */
}

.chat-box{
  flex: 1; /* takes the remaining height of the "container" div */
  overflow: auto; /* to scroll just the "main" div */
}

How to make element stretch vertically and not affect look?

2 Answers2

JSFiddle