* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html,
body {
    font-family: lato, sans-serif, Arial;
    font-size: 10px;  /* 1rem = 10px */
    min-height: 100vh;
}
body {
    background: linear-gradient(45deg, #16ebc4, #247061, #313132);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
.container {
    width: 30rem;
    height: 35rem;
    background: #eeeeee;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    border-radius: 5px;
    box-shadow: 0 0 8px 4px rgba(0,0,0,0.4);
    padding: 2rem;
}
.timer-box {
    background: white;
    border: 1px solid black;
    border-radius: 5px;
    padding: 1rem;
}
.timer {
    font-size: 4rem;
    font-weight: lighter;
}
.btn-wrapper {
    display: flex;
    justify-content: space-between;
    width: 15rem;
}
.btn {
    cursor: pointer;
    background: transparent;
    border: none;
    outline: none;
    width: 4rem;
}
.btn-svg {
    width: 4rem;
}
#btn-play{
    display: block;
}
#btn-pause{
    display: none;
}
/*
Icons made by <a href="https://www.flaticon.com/authors/freepik" title="Freepik">Freepik</a> from <a href="https://www.flaticon.com/" title="Flaticon"> www.flaticon.com</a>
Icons made by <a href="https://www.flaticon.com/authors/chanut" title="Chanut">Chanut</a> from <a href="https://www.flaticon.com/" title="Flaticon"> www.flaticon.com</a>
Icons made by <a href="https://www.flaticon.com/authors/pixel-perfect" title="Pixel perfect">Pixel perfect</a> from <a href="https://www.flaticon.com/" title="Flaticon"> www.flaticon.com</a>
*/