* {
    padding: 0;
    margin: 0;
}

body {
    height: 100vh;
    display: grid;
    grid-template-columns: 100%;
    grid-template-rows: 4rem 1fr 4rem;
}

#player {
    left: 100px;
    top: 300px;
    position: absolute;
    width: 50px;
    height: 50px;
    background-color: blue;
}

#header {
    text-align: center;
    background-color: black;
    color: white;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

#footer {
    background-color: lightgray;
}

#main {
    /* background-color: aqua; */
}

#title {
    margin-top: 0.5rem;
}

#startBtnContainer {
    display: flex;
    justify-content: center;
    align-items: center;
}

#startBtn {
    margin-top: 1rem;
    height: 2rem;
    width: 5rem;
}

#mainContainer {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 800px;
}

#map {
  position: relative;      
  width: 512px;      
  height: 384px;        
  border: 2px solid black;
}

.tile {
  position: absolute;
  width: 64px;
  height: 64px;
}

.air { background: #87CEEB; }    
.platform { background: green; }  
.spikes { background: black; }     
.water { background: blue; }