reset.css

body {
   background-image: url('image/background.jpg');
   margin: 0px;
   padding: 0px;
   font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
}

.img {
   text-align: center;
   background-color: black;
   padding-bottom: 1%;

}

h1 {
   text-align: center;
   margin-top: 2rem;
   margin-bottom: 1rem;
   margin-top: 1rem;
   margin-bottom: 1rem;
   color: #fff;
   font-size:4rem;  
   font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;

}
input {
   width: 20rem;
   height: 2rem;
   border-width: 1px;
   margin-bottom: 10px;
}

button {
   background-color: #2c87c3;
   padding: 5px;
   height: auto;
   margin-top: 1rem;
   color: white;
   width: 30%;
   border-radius: 0.2rem;
   text-align: center;
   padding: 6px;
   height: auto;
   margin-top: 10px;
   color: white;
   width: 30%;
   border-radius: 0.2rem;
   text-align: center;
   display: inline-block;
}

button:hover {
   background-color: #15679d;
}

form {
   text-align: center;
   display: block;
}

.box {
   
   background-color: transparent;
   backdrop-filter: blur(1px);
   padding-bottom: 8%;
   width: 30%;
   height: 10rem;
   margin-top:6rem;
   margin-left: auto;
   margin-right: auto;
   border-radius: 5px;
   border:1px solid rgba(247, 247, 247, 0.136);

}    
.btn-success {
   border: 2px solid rgb(8, 8, 8);
   padding: 6px;
   padding-bottom: 5.5px;
   margin-left: 18px;
   margin-top: 1rem;
   color: white;
   width: 30%;
   border-radius: 0.2rem;
   text-align: center;
   font-size: 1rem;
   margin-bottom: 5%;

}

.btn-success:hover {
   border: 2px solid rgb(8, 8, 8);
   border-radius: 0.2rem;
}