*, *::after, *::before {
    box-sizing: border-box;
}

body {
    display: grid;
    place-items: center;
    margin: 0 auto;
    background: #121212;
    height: 100vh;
}

.container {
    font-family: Arial, Helvetica, sans-serif;
    color: #fff;
    display: flex;
    position: relative;
    flex-direction: column;
    align-items: center;
}

#duration {
    font-size: 15vmin;
    margin-bottom: 2vh;
}

#activity {
    font-size: 10vmin;
    text-align: center;
}

#btn-container {
    text-align: center;
    margin-top: 4vh;
}

#btn {
    background-color: #fff;
    color: #2a3439;
    font-size: 8vmin;
    padding: 0.2em 1em;
    border: 0;
    border-radius: 30px;
}

small {
    font-size: 0.5em;
}

/* PWA special style */
.pwa {
    position: relative;
}

.pwa::before {
    position: absolute;
    transform-origin: top left;
    transform: rotate(90deg) translateY(-4em);
    content: 'POMODORO';
    font-size: 8em;
    width: 2ch;
    line-height: 6em;
    font-weight: 900;
    letter-spacing: 1px;
    padding: 0 10vw 0 0;
    margin: 0;
    color: #444;
    top: 0;
    left: 0;
}