css of my real time chat

@import url('https://fonts.googleapis.com/css2?family=Roboto&display=swap');

.sned_container {
    position: absolute;
    bottom: 10px;
    width: 100%;
    text-align: center;
}

.sned_container input {
    width: 80%;
    height: 30px;
    border: solid #333333 1px;
    border-radius: 7px;
}

.sned_container button{
    height: 35px;
    width: 100px;
    border: solid grey  1px;
    border-radius: 7px;
}



.this_message_parent {
    float: left;
    width: 70%;
    height: 40px;
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    flex-flow: column;
    border-radius: 10px 20px 20px 10px;
    font-size: 1.5em;
    position: relative;
    margin-top: 10px;
    animation-name: this_message_pop_in;
    animation-duration: 0.2s;
}

@keyframes this_message_pop_in{
    0%  {left: -80%; }
    75% {left: 8%; }
    100%{left: 0%; }
}

.this_message_backround{
    background-color: #333;
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 10px 20px 20px 10px;
}

.this_message_text{
    color: white;
    z-index: 1;
    margin-left: 10px;
    position: absolute;
    margin-bottom: 0px;
}



.partner_message_parent {
    float: right;
    width: 70%;
    height: 40px;
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    flex-flow: column;
    border-radius: 20px 10px 10px 20px;
    font-size: 1.5em;
    position: relative;
    margin-top: 10px;
    animation-name: this_message_pop_in;
    text-align: right;
    animation-duration: 0.2s;
}

@keyframes partner_message_pop_in{
    0%  {right: -80%; }
    75% {right: 8%; }
    100%{right: 0%; }
}

.partner_message_backround{
    background-color: #666;
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 20px 10px 10px 20px;
    right: 0;
}

.partner_message_text{
    color: white;
    z-index: 1;
    margin-right: 10px;
    position: absolute;
    right: 0;
    margin-bottom: 0px;
}

.type_anim{
    animation-name: type_anim_;
    animation-duration: 0.2s;
}

@keyframes type_anim_{
    50% {width: 103%; height: 110%;}
    100%{width: 100%; height: 100%;}
}

.end_message_anim{
    animation-name: end_message_anim_;
    animation-fill-mode: forwards;
    animation-duration: 0.3s;
}

@keyframes end_message_anim_{
    0% {width: 100%; height: 100%;}
    30% {width: 110%; height: 115%;}
    100%{width: var(--end_width); height: 100%;}
}

#input_area {
    position: fixed;
    height: 100%;
    width: 100%;
}

#input_area div {
    position: relative;
    height: 100%;
    width: 100%;
    display: flex;
    flex-flow: column;
    justify-content: center;
    text-align: center;
}

#message_container {
    display: inline-block;
    width: 100%;
}

#white_space {
    height: 550px;
}

body{
    margin: 0px;
}

.hidden{
    visibility: hidden;
}

.login_prompt {
    visibility: visible;
    width: 100%;
    height: 100%;
    background-image: linear-gradient(rgba(0, 0, 0, 0.6),rgba(0, 0, 0, 0.7),rgba(0, 0, 0, 0.7),rgba(0, 0, 0, 0.7),rgba(0, 0, 0, 0.6));
    position: fixed;
    top: 0px;
    z-index: 2;
    animation-name: login_prompt_anim;
    animation-timing-function: ease-out;
    animation-duration: 0.2s;
    display: flex;
    flex-flow: column;
    justify-content: center;
    align-items: center;
}

@keyframes login_prompt_anim{
    100%{height: 100%;}
}

.input{
    width: 50%;
    height: 30px;
    border-radius: 11px;
    background-color: seashell;
    margin: 10px 0px;
}

#username{

}

#password{
   visibility: hidden;
}

.login_text{
    font-size: 2em;
}

.modal-body{
    margin-top: 30px;
    margin-bottom:40px;
}

.this_username_parent {
    float: left;
    width: 70%;
    height: 40px;
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    flex-flow: column;
    border-radius: 20px 20px 20px 20px;
    font-size: 1.2em;
    position: relative;
    margin-top: 10px;
    animation-name: this_message_pop_in;
    animation-duration: 0.2s;
}

.this_username_backround{
    background-color: #333;
    position: absolute;
    width: 30%;
    height: 100%;
    border-radius: 20px 20px 20px 20px;
}

.this_username_text{
    color: whitesmoke;
    z-index: 1;
    margin-left: 10px;
    position: absolute;
    margin-bottom: 0px;
}




.partner_username_parent {
    float: right;
    width: 70%;
    height: 40px;
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    flex-flow: column;
    border-radius: 20px 20px 20px 20px;
    font-size: 1.2em;
    position: relative;
    margin-top: 10px;
    animation-name: this_message_pop_in;
    text-align: right;
    animation-duration: 0.2s;
}

.partner_username_backround{
    background-color: #666;
    position: absolute;
    width: 30%;
    height: 100%;
    border-radius: 20px 20px 20px 20px;
    right: 0;
}

.partner_username_text{
    color: whitesmoke;
    z-index: 1;
    margin-right: 10px;
    position: absolute;
    right: 0;
    margin-bottom: 0px;
}