instruction.css

body {
    height: 100vh;
    background: #8E0E00;
    /* fallback for old browsers */
    background: -webkit-linear-gradient(to bottom,
        #1F1C18,
        #8E0E00);
    );
    /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(to bottom,
        #1F1C18,
        #8E0E00);
    /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}

a,
a:hover {
    color: white;
    display: inline-block;
    text-decoration: none;
    font-weight: 400;
}

h2 {
    text-align: center;
    font-size: 16px;
    font-weight: 600;
    text-transform: uppercase;
    display: inline-block;
    margin: 40px 8px 10px 8px;
    color: #cccccc;
}

/* STRUCTURE */

.wrapper {
    display: flex;
    align-items: center;
    flex-direction: column;
    justify-content: center;
    width: 100%;
    min-height: 100%;
    padding: 20px;

    position: absolute;

    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
}

#Content {
    -webkit-border-radius: 10px 10px 10px 10px;
    border-radius: 10px 10px 10px 10px;
    background: #200000;
    /* fallback for old browsers */
    /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
    padding: 10px;
    width: 90%;
    max-width: 850px;
    position: relative;
    -webkit-box-shadow: 0 30px 60px 0 rgba(0, 0, 0, 0.3);
    box-shadow: 0 30px 60px 0 rgba(0, 0, 0, 0.3);
    text-align: center;
}

/* TABS */

h2.inactive {
    color: #cccccc;
}

h2.active {
    color: #0d0d0d7c;
    border-bottom: 2px solid #ff8c7f;
}

/* FORM TYPOGRAPHY*/

#button,
#sign-out {
    background-color: #1F1C18;
    border: none;
    color: white;
    padding: 15px 80px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    text-transform: uppercase;
    font-size: 13px;
    -webkit-box-shadow: 0 10px 40px #1F1C18;
    box-shadow: 0 10px 40px 0 #1F1C18;
    -webkit-border-radius: 5px 5px 5px 5px;
    border-radius: 5px 5px 5px 5px;
    margin: 5px 20px 40px 20px;
    -webkit-transition: all 0.3s ease-in-out;
    -moz-transition: all 0.3s ease-in-out;
    -ms-transition: all 0.3s ease-in-out;
    -o-transition: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
}

#button:hover,
#sign-out:hover {
    background-color: #8E0E00;
    -webkit-box-shadow: 0 12px 40px 1px #8E0E00;
    box-shadow: 0 12px 40px 1px #8E0E00;
}

#button:active,
#sign-out:active {
    -moz-transform: scale(0.95);
    -webkit-transform: scale(0.95);
    -o-transform: scale(0.95);
    -ms-transform: scale(0.95);
    transform: scale(0.95);
}


/* ANIMATIONS */

/* Simple CSS3 Fade-in-down Animation */
.fadeInDown {
    -webkit-animation-name: fadeInDown;
    animation-name: fadeInDown;
    -webkit-animation-duration: 1s;
    animation-duration: 1s;
    -webkit-animation-fill-mode: both;
    animation-fill-mode: both;
}

@-webkit-keyframes fadeInDown {
    0% {
        opacity: 0;
        -webkit-transform: translate3d(0, -100%, 0);
        transform: translate3d(0, -100%, 0);
    }

    100% {
        opacity: 1;
        -webkit-transform: none;
        transform: none;
    }
}

@keyframes fadeInDown {
    0% {
        opacity: 0;
        -webkit-transform: translate3d(0, -100%, 0);
        transform: translate3d(0, -100%, 0);
    }

    100% {
        opacity: 1;
        -webkit-transform: none;
        transform: none;
    }
}

/* Simple CSS3 Fade-in Animation */
@-webkit-keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@-moz-keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.fadeIn {
    opacity: 0;
    -webkit-animation: fadeIn ease-in 1;
    -moz-animation: fadeIn ease-in 1;
    animation: fadeIn ease-in 1;

    -webkit-animation-fill-mode: forwards;
    -moz-animation-fill-mode: forwards;
    animation-fill-mode: forwards;

    -webkit-animation-duration: 1s;
    -moz-animation-duration: 1s;
    animation-duration: 1s;
}

.fadeIn.first {
    -webkit-animation-delay: 0.4s;
    -moz-animation-delay: 0.4s;
    animation-delay: 0.4s;
    margin: 20px;
    color: white;
}

.fadeIn.second {
    -webkit-animation-delay: 0.6s;
    -moz-animation-delay: 0.6s;
    animation-delay: 0.6s;
    margin: 20px;
}

.fadeIn.third {
    -webkit-animation-delay: 0.8s;
    -moz-animation-delay: 0.8s;
    animation-delay: 0.8s;
    margin: 20px;
}

.fadeIn.fourth {
    -webkit-animation-delay: 1s;
    -moz-animation-delay: 1s;
    animation-delay: 1s;
    margin: 20px;
}

.fadeIn.fifth {
    -webkit-animation-delay: 1.2s;
    -moz-animation-delay: 1.2s;
    animation-delay: 1.2s;
    margin: 8px;
    color: white;
    text-align: left;
}

/* Simple CSS3 Fade-in Animation */
.underlineHover:after {
    display: block;
    left: 0;
    bottom: -10px;
    width: 0;
    height: 2px;
    background-color: white;
    content: "";
    transition: width 0.2s;
}

.underlineHover:hover {
    color: red;
    text-decoration: none;
}

.underlineHover:hover:after {
    width: 100%;
}

/* OTHERS */

*:focus {
    outline: none;
}

#icon {
    width: 60%;
}