login.css

body {
  margin: 0;
  padding: 0;
  /* background-image: url(s_images/003.jpg); */
  background-size: 100% 120%;
  background-position: absolute;
  font-family: sans-serif;
}
.loginbox {
  width: 340px;
  height: 450px;
  background: rgb(53, 48, 48);
  color: #fff;
  top: 50%;
  left: 50%;
  position: absolute;
  transform: translate(-50%, -50%);
  box-sizing: border-box;
  padding: 70px 30px;
  border-radius: 50px;
}
.avatar {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  position: absolute;
  top: -50px;
  left: calc(50% - 50px);
}
h1 {
  margin: 0;
  padding: 0 0 20px;
  text-align: center;
  font-size: 22px;
}
.loginbox p {
  margin: 0;
  padding: 0;
  font-weight: bold;
}
.loginbox input {
  width: 100%;
  margin-bottom: 20px;
}

.loginbox input[type="mail"],
input[type="password"] {
  border: none;
  border-bottom: 1px solid #fff;
  background: transparent;
  outline: none;
  color: yellowgreen;
  height: 40px;
  font-size: 16px;
}

.loginbox input[type="submit"] {
  border: none;
  outline: none;
  height: 40px;
  background: rgb(10, 122, 156);
  color: #fff;
  font-size: 18px;
  border-radius: 20px;
  width: 120px;
  margin-bottom: 0;
}

.loginbox input[type="submit"]:hover {
  cursor: pointer;
  background: rgb(196, 240, 3);
  color: #000;
}

.loginbox a {
  text-decoration: none;
  font-size: 12px;
  line-height: 20px;
  color: darkgrey;
}
.loginbox a:hover {
  color: #ffc107;
}
h4 {
  margin-top: 0;
  margin-bottom: 15;
}