style.css

body {
    background-color:hsl(185, 41%, 84%);
    font-family: 'Space Mono', monospace;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

#app {
    display: flex column;
    justify-content: center;
    align-items: center;
    position: absolute;
    
}

header{
    position: relative;
    margin: 0 auto;
    display: flex;
    justify-content: center;
    top: -400px;
}


input {
    text-align: right;
    font-family: 'Space Mono', monospace;
    font-size: 24px;
    width: 100%;
    border: none;
    background-color: hsl(189, 41%, 97%);
    color: hsl(183, 100%, 15%);
    line-height: 55px;
    border-radius: 8px;
    margin-bottom: 50px;
    margin-top: 20px;
    padding-right: 10px;
}

input::-webkit-outer-spin-button,
input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input[type$="number"]:focus {
    outline: 2px solid hsl(172, 67%, 45%);  
    box-shadow: 0 0 5px hsl(172, 67%, 45%);
}

.error-style {
    outline: 2px solid hsl(11, 86%, 38%);  
    box-shadow: 0 0 5px hsl(11, 86%, 38%);
}
.error-style:focus {
    outline: 2px solid hsl(11, 86%, 38%)  !important;  
    box-shadow: 0 0 5px hsl(11, 86%, 38%) !important;
}

h1 {
    font-size: 50px;
    padding-top: 28px;
    margin: 0 auto;

}

h2{
    font-size: 18px;
    margin: 0 auto;
    padding: 40px 20px 0;
}

p {
    font-size: 14px;
    color: hsl(184, 14%, 56%);
    padding: 10px 20px 10px;
    margin: 0 auto;
}
    

::placeholder {
    color: hsl(184, 14%, 56%);
}

#custom-tip {
    width: 27%;
    text-align: center;
    margin-top: 20px;

}

#right-content {
    width: 50%;
    margin: 30px;
    padding: 20px;
    background-color:hsl(183, 100%, 15%);
    color:hsl(189, 41%, 97%);
    border-radius: 30px;
}

#numbers {
    text-align: right;
    float: right;
    color: hsl(172, 67%, 45%);
    margin-right: 10px;
}

#send-left {
    text-align: left;
}

#left-content {
    margin: 30px;
    padding-top:30px;
    padding-left: 20px;
    padding-right: 20px;
    width: 50%;
}


.radio-toolbar input[type="radio"] {
    opacity: 0;
    position: fixed;
    width: 0;
  }
  
button {
    font-family: 'Space Mono', monospace;
    font-size: 24px;
    height: 55px;
    width: 30%;
    border-radius: 8px;
    background-color:hsl(183, 100%, 15%);
    border: none;
    margin-top: 20px;
    color:hsl(189, 41%, 97%);
    font-weight: bold;
}

button:hover{
    background-color: hsl(172, 57%, 75%);
    color: hsl(183, 100%, 15%);
    cursor: pointer;
}

/*button:focus,
button:active {
    background-color: hsl(172, 67%, 45%);
    color: hsl(183, 100%, 15%);
}*/

.selected {
    background-color: hsl(172, 67%, 45%);
    color: hsl(183, 100%, 15%);
}

#reset-button{
    width: 100%;
    text-align: center;
    background-color: hsl(172, 67%, 45%);
    margin-top: 220px;
    margin-bottom: 0;

}

#reset-button:hover{
    background-color: hsl(172, 57%, 75%);
    color: hsl(183, 100%, 15%);
}

#zero-alert {
    font-size: 14px;
    visibility: hidden;
}

#percentage-buttons{
    display: flex;
    flex-flow: wrap;
    justify-content: space-between;
    margin-bottom: 0px;    
}

.square-background{
    width: 100%;
    height: 100%;
    background-color: white;
    border-radius: 30px;
    margin: auto;
    color: hsl(186, 14%, 43%);
    display: flex;    
}

.icon-inside {
    position:relative;
   }

.icon-inside i {
    position:absolute;
    left:0;
    top: 23%;
    padding: 10px 20px;
   }


   @media screen and (max-width: 800px) {

    
    .square-background{
        display: flex;
        flex-direction: column;
        width: 100%;
        margin-top: 150px;
        align-content: center;
        align-items: center;
    }

    body{
        align-items: flex-start;
    }

    button {
        font-size: 22px;
        height: 45px;
        border-radius: 4px;
        width: 48%;
    }

    #reset-button{
        margin-top: 40px;
    }

    #custom-tip {
        width: 45%;
    
    }

    h3 {
        font-size: 35px;
    }
    
    h6{
        font-size: 15px;
    }
    
    p {
        font-size: 13px;
    }

    header {
        top: 50px;
    }
    
    #right-content {
        width: 80%;
        border-radius: 20px;
    }
      
    #send-left {
        text-align: left;
        width: 50%;
    
    }
    
    #left-content {
        width: 80%;      
    }

    input {
        font-size: 22px;
        line-height: 45px;
        border-radius: 8px;
    }

    .icon-inside i {
        padding: 5px 10px;
       }

    #icon-2 i{
        top: 40%;
    }

    #number-of-people{
        margin-bottom: 0px;
    }

    #total-amount-final{
        margin-top: 20px;
    }

  }