:root {
    font-family: "Open Sans", Inter, system-ui, Avenir, Helvetica, Arial, sans-serif;
    line-height: 1.5;
    font-weight: 400;

    font-synthesis: none;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    margin: 0;
}

main {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background-color: #e0e0e0;
    box-sizing: border-box;
    padding: 1em;
}

h1 {
    font-size: 3em;
    line-height: 1.1;
    margin: 1.25em 0;
    text-wrap: balance;
    padding-left: 0.5em;
}

button {
    appearance: none;
    border-radius: 0;
    border: 0;
    padding: 0;
    font-size: 1em;
    font-weight: 500;
    font-family: inherit;
}

    article {
        opacity: 0.8;
        label {
            display: block;
            padding: 1em 0.66em;

            input {
                grid-area: input;
                position: absolute;
                opacity: 0;
                pointer-events: none;
            }
            strong {
                display: block;
                font-size: 1.25em;
            }
            small {
                grid-area: date;
            }
        }
}
    article:has(:checked) {
        opacity: 0.25;

        + article:not(:has(:checked)) {
            opacity: 1;
        }
    }

.clickable {
    box-shadow: 0 3px 0 rgba(0, 0, 0, .75);
    border: 2px solid #222;
    border-radius: 8px;
    background-color: #f1f1f1;
    display: block;

    &:hover, &:focus {
        background-color: #e1e1e1;
    }

    &:active {
        transform: translateY(1px);
    }
}

.back {
    background-color: #e0e0e0;
    color: #000;

    &:hover, &:focus {
        background-color: #d0d0d0;
    }
}

    .calendar {
        display: grid;
        grid-template-columns: 1fr 1fr 1fr;
        gap: 2em 0.5em;
    }

    header {
        display: flex;
        padding: 1em;
        gap: 0.5em;
        align-items: center;

        button {
            padding: 0.5em 1em;
        }

        h1 {
            font-size: 1.25em;
            flex: 1;
            margin: 0;
        }
    }