* {
    list-style: none;
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Poppins', sans-serif;
}

body {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #181616;
}

nav {
    width: 70px;
    height: 450px;
    background: #1b1a1a;
    text-align: center;
    border-radius: 10px;
    box-shadow: inset 0 0 4px rgba(255, 255, 255, .1),
                inset 3px 3px 8px rgba(255, 255, 255, .1);
    transition: .4s;
}

nav li {
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 70px;
    color: #ffffff;
    opacity: .9;
    transition: .4s;
}

nav li:hover {
    color: #0cebc5;
    transform: scale(1.1);
    opacity: 1;
}

nav .brand {
    color: #0cebc5;
    font-size: 28px;
    margin-top: 30px;
}

nav li i {
    position: absolute;
    font-size: 26px !important;
    transition: .4s;
}

nav li a {
    position: absolute;
    font-size: 18px;
    letter-spacing: 1px;
    opacity: 0;
    transition: .4s;
}

nav label {
    cursor: pointer;
    color: #ffffff;
    background: #1b1a1a;
    font-size: 24px !important;
    width: 40px;
    height: 40px;
    padding: 6px 18px;
    border-radius: 50%;
    transform: translateX(35px) translateY(8px);
    border-right: 1px solid rgba(255, 255, 255, .1);
    transition: .4s;
}

nav label:hover {
    color: #0cebc5;
}

input:checked ~ nav {
    width: 180px;
}

input:checked ~ nav label {
    transform: translateX(90px) translateY(10px) rotate(180deg);
    padding-left: 10px;
    border-right: 0;
    border-left: 1px solid rgba(255, 255, 255, .1);
}

input:checked ~ nav li i {
    padding-right: 100px;
}

input:checked ~ nav li a {
    padding-left: 40px;
    opacity: 1;
}

input {
    display: none;
}
a{
    color: #ffffff;
    text-decoration: none;
}
a:hover{
    text-decoration: underline;
}