:root
{
    --building-color1: #aa80ff;
    --building-color2: #66cc99;
    --building-color3: #cc6699;
    --building-color4: #538cc6;
    --window-color1: #bb99ff;
    --window-color2: #8cd9b3;
    --window-color3: #d98cb3;
    --window-color4: #8cb3d9;
}
*
{
    box-sizing: border-box;
}
body
{
    height: 100vh;
    margin: 0;
    overflow: hidden;
}
.background-buildings, .foreground-buildings
{
    width: 100%;
    height: 100%;
    top: 0;
    position: absolute;
    display: flex;
    align-items: flex-end;
    justify-content: space-evenly;
}
.building-wrap
{
    display: flex;
    flex-direction: column;
    align-items: center;
}
.window-wrap
{
    display: flex;
    align-items: center;
    justify-content: space-evenly;
}
.sky
{
    background: radial-gradient(circle closest-corner at 15% 15%,#ffcf33 0%, #ffcf33 20%, #ffff66 21%, #bbeeff 100%);
}
/* BACKGROUND BUILDINGS - "bb" stands for "background building" */
.bb1
{
    width: 10%;
    height: 70%;

}
.bb1-window
{
    height: 10%;
    background: linear-gradient(var(--building-color1),var(--window-color1));
}
.bb1a
{
    width: 70%;
}
.bb1b
{
    width: 80%;
}
.bb1c
{
    width: 90%;
}
.bb1d
{
    width: 100%;
    height: 70%;
    background: linear-gradient(orange, var(--building-color1)  50%, var(--window-color1));
}
.bb2
{
    width: 10%;
    height: 50%;
}
.bb2a
{
    border-bottom: 5vh solid var(--building-color2);
    border-left: 5vw solid transparent;
    border-right: 5vw solid transparent;
}
.bb2b
{
    width: 100%;
    height: 100%;
    background: repeating-linear-gradient(var(--building-color2) 0%, var(--building-color2) 6%, var(--window-color2) 6%, var(--window-color2) 9%);
}
.bb3
{
    width: 10%;
    height: 55%;
    background: repeating-linear-gradient(90deg, var(--building-color3), var(--window-color3) 15%);
}
.bb4
{
    width: 11%;
    height: 58%;
}
.bb4a
{
    width: 3%;
    height: 10%;
    background-color: var(--building-color4);
}
.bb4b
{
    width: 80%;
    height: 5%;
    background-color: var(--building-color4);
}
.bb4c
{
    width: 100%;
    height: 85%;
    background-color: var(--building-color4);
}
.bb4-window
{
    width: 18%;
    height: 90%;
    background-color: var(--window-color4);
}
/* FOREGROUND BUILDINGS - "fb" stands for "foreground building" */
.fb1
{
    width: 10%;
    height: 60%;
}
.fb1a
{
    border-bottom: 7vh solid var(--building-color4);
    border-left: 2vw solid transparent;
    border-right: 2vw solid transparent;
}
.fb1b
{
    width: 60%;
    height: 10%;
    background-color: var(--building-color4);
}
.fb1c
{
    width: 100%;
    height: 80%;
    background: repeating-linear-gradient(90deg, var(--building-color4) 0%, var(--building-color4) 10%, transparent 10%, transparent 15%),
    repeating-linear-gradient(var(--building-color4) 0%, var(--building-color4) 10%, var(--window-color4) 10%, var(--window-color4) 90%);
}
.fb2
{
    width: 10%;
    height: 40%;
    background-color: var(--building-color2);
}
.fb2a
{
    width: 100%;
    border-bottom: 10vh solid var(--building-color3);
    border-right: 1vw solid transparent;
    border-left: 1vw solid transparent;
}
.fb2b
{
    width: 100%;
    height: 75%;
    background-color: var(--window-color3);
}
.fb2-window
{
    width: 22%;
    height: 100%;
    background-color: var(--window-color3);
}
.fb3
{
    width: 10%;
    height: 35%;
}
.fb3a
{
    width: 80%;
    height: 15%;
    background-color: var(--building-color1);
}
.fb3b
{
    width: 100%;
    height: 35%;
    background-color: var(--building-color1);
}
.fb3-window
{
    width: 25%;
    height: 80%;
    background-color: var(--window-color1);
}
.fb4
{
    width: 8%;
    height: 45%;
    position: relative;
    left: 10%;
}
.fb4a
{
    border-top: 5vh solid transparent;
    border-left: 8vw solid transparent;
}
.fb4b
{
    width: 100%;
    height: 89%;
    background-color: var(--building-color1);
    display: flex;
    flex-wrap: wrap;
}
.fb4-window
{
    width: 30%;
    height: 10%;
    border-radius: 50%;
    margin: 10%;
}
.fb5
{
    width: 10%;
    height: 33%;
    position: relative;
    right: 10%;
    background: repeating-linear-gradient(var(--building-color2) 0%, var(--building-color2) 5%, transparent 5%, transparent 10%),
    repeating-linear-gradient(90deg, var(--building-color2) 0%, var(--building-color2) 12%, var(--window-color2) 12%, var(--window-color2) 44%);
}
.fb6
{
    width: 9%;
    height: 38%;
    background: repeating-linear-gradient(90deg, var(--building-color3) 0%, var(--building-color3) 10%, transparent 10%, transparent 30%),
    repeating-linear-gradient(var(--building-color3) 0%, var(--building-color3) 10%, var(--window-color3) 10%, var(--window-color3) 30%);
}
@media (max-width:1000px){
    :root
    {
        --building-color1: #000;
        --building-color2: #000;
        --building-color3: #000;
        --building-color4: #000;
        --window-color1: #777;
        --window-color2: #777;
        --window-color3: #777;
        --window-color4: #777;
    }   
    .sky
    {
        background: radial-gradient(circle closest-corner at 15% 15%,#ccc 0%, #ccc 20%, #445 21%, #223 100%);
    }
}