*, *::before, *::after {
    box-sizing:border-box;
    font-family: 'Play', sans-serif;
    font-weight: normal;
}

h1 {
    margin-bottom: -50px;
    text-align: center;
    color:floralwhite;
}

h1:hover {
    transform: scale(1.5);
}

body {
    padding: 0;
    margin: 0;
    background: linear-gradient(to right, #55665d, #128341);
}

.calculator-grid {
    display: grid;
    justify-content: center;
    align-content: center;
    min-height: 100vh;
    grid-template-columns: repeat(4, 100px);
    grid-template-rows: minmax(120px, auto) repeat(5, 100px);
    border-radius: 2%;
}

@media only screen and (min-width: 800px) {
    .calculator-grid {
        position: fixed;
        bottom: 0;
        top: 0;
        left: 750px;
        width: 400px;
    }
  }

.calculator-grid > button {
    cursor: pointer;
    font-size: 2rem;
    border: 1px solid white;
    outline: none;
    background-color: rgba(255, 255, 255, 0.75);
    border-radius: 10%;
    margin: 3%;
    
}

.calculator-grid > button:hover {
    background-color: rgba(128, 240, 118, 0.9);
    transform: scale(1.05);
}

.span-two {
    grid-column: span 2;
}

.output {
    grid-column: 1 / -1;
    background-color: rgba(248, 248, 248, 0.75);
    display: flex;
    align-items: flex-end;
    justify-content: space-around;
    flex-direction: column;
    padding: 10px;
    word-wrap:break-word;
    word-break: break-all;
    border-radius: 3%;
    margin-bottom: 2%;
}

.output .previous-operand {
    color: rgba(255, 255, 255, 0.75);
    font-size: 2rem;
}

.output .previous-operand {
    color: white;
    font-size: 3rem;
}

.output .current-operand {
    color: rgb(44, 48, 45);
    font-size: 3rem;
}

#particles-js {
  width:100%;
  height:100%;
  background-size:cover;
  position: absolute; 
  z-index: -1;
}