* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  background-color: #020024;
}

.bgg {
  position: fixed;
  z-index: 1;
  height: 400px;
  width: 500px;
  left: 50%;
  margin-left: -255px;
  margin-top: 10%;
  border: 20px solid #5d1818;
  border-top-color: #2b0909;
  border-right-color: #3c0c0c;
  border-left-color: #4a1010;
}

.window{
    position: absolute;
    height: 100%;
    width: 100%;
    background: url(https://images.unsplash.com/20/cold-city.JPG?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=500&q=60);
    z-index: 1;
    opacity: 0.5;
    background-size: cover;
}

.bgg .snowflake, .bgg .snowflake {
  position: absolute;
  font-size: 25px;
  color: #fff;
  height: 100%;
  animation: snow infinite;
}

.snow {
    position: absolute;
    z-index: 2;
    width: 459px;
    height: 0;
    background-color: #fff;
    bottom: 0;
    animation: windowSnow 10s ease-in infinite forwards;
}

.snowflake:nth-of-type(1) {
  left: 0%;
  animation-delay: 0s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(2) {
  left: 10%;
  animation-delay: 0.1s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(3) {
  left: 20%;
  animation-delay: 0.2s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(4) {
  left: 30%;
  animation-delay: 0.3s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(5) {
  left: 40%;
  animation-delay: 0.4s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(6) {
  left: 10%;
  animation-delay: 0.5s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(7) {
  left: 15%;
  animation-delay: 0s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(8) {
  left: 20%;
  animation-delay: 0.1s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(9) {
  left: 25%;
  animation-delay: 0.2s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(10) {
  left: 30%;
  animation-delay: 0.3s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(11) {
  left: 35%;
  animation-delay: 0.4s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(12) {
  left: 40%;
  animation-delay: 0.5s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(13) {
  left: 45%;
  animation-delay: 0s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(14) {
  left: 50%;
  animation-delay: 0.1s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(15) {
  left: 55%;
  animation-delay: 0.2s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(16) {
  left: 60%;
  animation-delay: 0.3s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(17) {
  left: 65%;
  animation-delay: 0.4s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(18) {
  left: 70%;
  animation-delay: 0.5s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(19) {
  left: 75%;
  animation-delay: 0s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(20) {
  left: 80%;
  animation-delay: 0.1s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(21) {
  left: 85%;
  animation-delay: 0.2s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(22) {
  left: 90%;
  animation-delay: 0.3s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(23) {
  left: 95%;
  animation-delay: 0.4s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(24) {
  left: 5%;
  animation-delay: 0.5s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(25) {
  left: 50%;
  animation-delay: 0s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(26) {
  left: 60%;
  animation-delay: 0.1s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(27) {
  left: 70%;
  animation-delay: 0.2s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(28) {
  left: 80%;
  animation-delay: 0.3s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(29) {
  left: 90%;
  animation-delay: 0.4s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(30) {
  left: 95%;
  animation-delay: 0.5s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(31) {
  left: 7%;
  animation-delay: 0s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(32) {
  left: 17%;
  animation-delay: 0.1s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(33) {
  left: 27%;
  animation-delay: 0.1s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(34) {
  left: 37%;
  animation-delay: 0.2s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(35) {
  left: 47%;
  animation-delay: 0.3s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(36) {
  left: 57%;
  animation-delay: 0.4s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(37) {
  left: 67%;
  animation-delay: 0.5s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(38) {
  left: 77%;
  animation-delay: 0s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(39) {
  left: 87%;
  animation-delay: 0.1s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(40) {
  left: 95%;
  animation-delay: 0.2s;
  animation-duration: 3s;
}

.snowflake:nth-of-type(41) {
  left: 3%;
  animation-delay: 0.3s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(42) {
  left: 23%;
  animation-delay: 0.4s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(43) {
  left: 53%;
  animation-delay: 0.5s;
  animation-duration: 1s;
}

.snowflake:nth-of-type(44) {
  left: 73%;
  animation-delay: 0s;
  animation-duration: 2s;
}

.snowflake:nth-of-type(45) {
  left: 93%;
  animation-delay: 0.1s;
  animation-duration: 3s;
}

ul {
  list-style-type: none;
}

@keyframes snow {
  0% {transform: skewX(0deg) translateY(-3%);}
  5% {transform: skewX(1deg) translateY(5%);}
  10% {transform: skewX(2deg) translateY(10%);}
  15% {transform: skewX(3deg) translateY(15%);}
  20% {transform: skewX(4deg) translateY(20%);}
  25% {transform: skewX(5deg) translateY(25%);}
  30% {transform: skewX(6deg) translateY(30%);}
  35% {transform: skewX(7deg) translateY(35%);}
  40% {transform: skewX(8deg) translateY(40%);}
  45% {transform: skewX(9deg) translateY(45%);}
  50% {transform: skewX(10deg) translateY(50%);}
  55% {transform: skewX(9deg) translateY(55%);}
  60% {transform: skewX(8deg) translateY(60%);}
  65% {transform: skewX(7deg) translateY(65%);}
  70% {transform: skewX(6deg) translateY(70%);}
  75% {transform: skewX(5deg) translateY(75%);}
  80% {transform: skewX(4deg) translateY(80%);}
  85% {transform: skewX(3deg) translateY(85%);}
  90% {transform: skewX(2deg) translateY(90%);}
  95% {transform: skewX(1deg) translateY(95%);}
  100% {transform: skewX(0deg) translateY(97%);}
}

@keyframes windowSnow {
  0% {height: 1px;}
  5% {height: 3px;}
  10% {height: 5px;}
  15% {height: 7px;}
  20% {height: 10px;}
  25% {height: 15px;}
  30% {height: 20px;}
  35% {height: 25px;}
  40% {height: 30px;}
  45% {height: 35px;}
  50% {height: 40px;}
  70% {opacity: 0.9;}
  75% {opacity: 0.8;}
  80% {opacity: 0.7;}
  85% {opacity: 0.5;}
  90% {opacity: 0.3;}
  95% {opacity: 0.2;}
  100% {opacity: 0.1;}