body {
    font-family: courier, courier new, serif;
    background: #3C3F42 none no-repeat center top fixed !important;
    background-size: cover !important;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}
#preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: black;
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
}
#preloader video {
    max-width: 100%;
    max-height: 100vh;
    width: auto;
    height: auto;
}
#mainContent {
    display: none;
    width: 100%;
    flex: 1;
    position: relative;
}
main {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
}
input[type=text], input[type=password] {
    width: 100%;
    padding: 12px 20px;
    margin: 8px 0;
    display: inline-block;
    border: 1px solid #ccc;
    box-sizing: border-box;
}

/* Animated button with border effect */
button {
    background: linear-gradient(-30deg, #3498DB 50%, #2980B9 50%);
    color: white;
    padding: 14px 20px;
    margin: 8px 0;
    border: none;
    cursor: pointer;
    width: 100%;
    font-weight: bold;
    position: relative;
    overflow: hidden;
    border-radius: 4px;
}

button::before {
    content: '';
    position: absolute;
    top: 0px;
    left: 0px;
    width: 100%;
    height: 100%;
    background-color: #5DADE2;
    opacity: 0;
    transition: .2s opacity ease-in-out;
    border-radius: 4px;
}

button:hover {
    color: black;
}

button:hover::before {
    opacity: 0.2;
}

/* Animation spans for button */
button span {
    position: absolute;
}

button span:nth-child(1) {
    top: 0px;
    left: 0px;
    width: 100%;
    height: 2px;
    background: linear-gradient(to left, rgba(41, 128, 185, 0), #1B4F72);
    animation: 2s animateTop linear infinite;
}

button span:nth-child(2) {
    top: 0px;
    right: 0px;
    height: 100%;
    width: 2px;
    background: linear-gradient(to top, rgba(41, 128, 185, 0), #1B4F72);
    animation: 2s animateRight linear -1s infinite;
}

button span:nth-child(3) {
    bottom: 0px;
    left: 0px;
    width: 100%;
    height: 2px;
    background: linear-gradient(to right, rgba(41, 128, 185, 0), #1B4F72);
    animation: 2s animateBottom linear infinite;
}

button span:nth-child(4) {
    top: 0px;
    left: 0px;
    height: 100%;
    width: 2px;
    background: linear-gradient(to bottom, rgba(41, 128, 185, 0), #1B4F72);
    animation: 2s animateLeft linear -1s infinite;
}

/* Animation keyframes */
@keyframes animateTop {
    0% {
        transform: translateX(100%);
    }
    100% {
        transform: translateX(-100%);
    }
}

@keyframes animateRight {
    0% {
        transform: translateY(100%);
    }
    100% {
        transform: translateY(-100%);
    }
}

@keyframes animateBottom {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

@keyframes animateLeft {
    0% {
        transform: translateY(-100%);
    }
    100% {
        transform: translateY(100%);
    }
}

.imgcontainer {
    text-align: center;
    margin: 24px 0 12px 0;
}
img.avatar {
    vertical-align: middle;
    width: 262px;
    height: 68px;
}
.container {
    padding: 16px;
}
span.psw {
    float: right;
    padding-top: 16px;
}
form {
    border: 3px solid #f1f1f1;
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
    background-color: white;
    border-radius: 3px;
    box-sizing: border-box;
}
@media screen and (max-width: 300px) {
    span.psw {
        display: block;
        float: none;
    }
}
@media screen and (min-width: 1200px) {
    #mainContent {
        padding: 40px;
    }
}