*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
:root{
    font-size: 62.5%;

    --color-primary:hsl(235,35%,19%);
    --color-secondary:hsl(358,78%,69%);
    --color-font:hsla(0,0%,100%,0.982);

    --color-shadow: hsl(235,36%,35%);
}
html, body{
    height: 100%;
    background-color: var(--color-primary);
    font-size: 1.6rem;
    font-family: 'Open sans',sans-serif;
}

p,
i,
h1{
    color: var(--color-font);
}
i{
    font-size: 4.6rem;
}

/*===== content ======*/
section {
    display: flex;
    align-items: center;
    height: 100%;
}
.container{
    width: min(42.5rem, 100%);
    margin-inline: auto ;
    padding-inline: 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
}
.panel{
    display: grid;
    grid-template-columns: 1fr 1fr;
    text-align: center;
    width: 28rem;
    margin-block: 5rem;
    padding: 1rem;
    border-radius: 10rem;
    -webkit-box-shadow: 0px 0px 15px 10px var(--color-shadow);
    box-shadow: 0px 0px 15px 10px var(--color-shadow);
}
.panel p{
    opacity: .8;
    transition: 1s ease-in;
}
.panel p.active{
    opacity: 1;
    color: var(--color-secondary);
}
.timer{
    display: flex;
    justify-content: center;
    align-items: center;
    width: 32rem;
    height: 32rem;
    border-radius: 50%;
    -webkit-box-shadow: 0px 0px 15px 10px var(--color-shadow);
    box-shadow:0px 0px 15px 10px var(--color-shadow);
}
    .circle{
        display: flex;
        justify-content: center;
        align-items: center;
        width: 26rem;
        height: 26rem;
        border-radius: 50%;
        background-color: var(--color-secondary);
        position: relative;
    }
    .circle::before{
        content: '';
        position: absolute;
        width: 95%;
        height: 95%;
        border-radius: 50%;
        background-color: var(--color-primary);
    }

    .time{
        position: relative;
        display: flex;
    }
    .time p{
        font-size: 5.6rem;
    }
    .time p:nth-of-type(2){
        position: relative;
        top: -.5rem;
        margin-inline: 1rem;
    }
    .controls{
        margin-top: 3rem;
    }
    .controls button{
        border: none;
        background: transparent;
        cursor: pointer;
    }
    .controls #reset{
        display: none;
    }