* {
    box-sizing: border-box;
    font-family: 'Segoe UI', sans-serif;
}
 
body {
    height: 100vh;
    background: #f0f0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0;
}
 
.container {
    background: #fff;
    width: 1000px;
    height: 550px;
    border-radius: 12px;
    box-shadow: 0 20px 40px rgba(0,0,0,.3);
    overflow: hidden;
    position: relative;
}
 
/* FORMULÁRIOS */
.form-container {
    position: absolute;
    width: 50%;
    height: 100%;
    padding: 60px;
    transition: all .6s ease-in-out;
}
 
.form-container h2 {
    margin-bottom: 20px;
    color: #000;
}
 
.form-container input {
    width: 100%;
    padding: 12px;
    margin: 10px 0;
    border: 1px solid #000;
    outline: none;
}
 
.form-container button {
    margin-top: 15px;
    padding: 12px;
    width: 100%;
    background: #000;
    color: #fff;
    border: none;
    cursor: pointer;
    transition: .3s;
}
 
.form-container button:hover {
    background: #333;
}
 
/* POSIÇÃO */
.login {
    left: 0;
    z-index: 2;
}
 
.register {
    left: 0;
    opacity: 0;
    z-index: 1;
}
 
/* ANIMAÇÃO */
.container.active .login {
    transform: translateX(100%);
    opacity: 0;
}
 
.container.active .register {
    transform: translateX(100%);
    opacity: 1;
    z-index: 5;
}
 
/* OVERLAY */
.overlay-container {
    position: absolute;
    left: 50%;
    width: 50%;
    height: 100%;
    background: #000;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform .6s ease-in-out;
}
 
.container.active .overlay-container {
    transform: translateX(-100%);
}
 
.overlay {
    text-align: center;
    padding: 40px;
}
 
.overlay h2 {
    margin-bottom: 10px;
}
 
.overlay button {
    margin-top: 20px;
    padding: 12px 30px;
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
    cursor: pointer;
    transition: .3s;
}
 
.overlay button:hover {
    background: #fff;
    color: #000;
}
 
.input-box{
    position: relative;
    margin: 12px 0;
}

.input-box input{
    width: 100%;
    padding: 12px 40px 12px 12px;
}

.input-box i{
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: #555;
}