@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@300;500;700&display=swap");

.timeline > *,
.timeline > *::before,
.timeline > *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.timeline {
    --color: rgba(30, 30, 30);
    --bgColor: rgba(245, 245, 245);
    --bgColorCard: Azure;
    display: grid;
    align-content: center;
    gap: 2rem;
    padding: 2rem;
    font-family: "Poppins", sans-serif;
    color: var(--color);
    background: var(--bgColor);
}


    .timeline > h1 {
        text-align: center;
    }

    .timeline > ul {
        --col-gap: 2rem;
        --row-gap: 2rem;
        --line-w: 0.25rem;
        display: grid;
        grid-template-columns: var(--line-w) 1fr;
        grid-auto-columns: max-content;
        column-gap: var(--col-gap);
        list-style: none;
        width: min(60rem, 90%);
        margin-inline: auto;
    }

        /* line */
        .timeline > ul::before {
            content: "";
            grid-column: 1;
            grid-row: 1 / span 20;
            background: rgb(225, 225, 225);
            border-radius: calc(var(--line-w) / 2);
        }

        /* columns*/

        /* row gaps */
        .timeline > ul li:not(:last-child) {
            margin-bottom: var(--row-gap);
        }

        /* card */
        .timeline > ul li {
            grid-column: 2;
            --inlineP: 1.5rem;
            margin-inline: var(--inlineP);
            grid-row: span 2;
            display: grid;
            grid-template-rows: min-content min-content min-content;
        }

            /* date */
            .timeline > ul li .date {
                --dateH: 3rem;
                height: var(--dateH);
                margin-inline: calc(var(--inlineP) * -1);
                text-align: center;
                background-color: var(--accent-color);
                color: white;
                font-size: 1.5rem;
                font-weight: 700;
                display: grid;
                place-content: center;
                position: relative;
                border-radius: calc(var(--dateH) / 2) 0 0 calc(var(--dateH) / 2);
            }

                /* date flap */
                .timeline > ul li .date::before {
                    content: "";
                    width: var(--inlineP);
                    aspect-ratio: 1;
                    background: var(--accent-color);
                    background-image: linear-gradient(rgba(0, 0, 0, 0.2) 100%, transparent);
                    position: absolute;
                    top: 100%;
                    clip-path: polygon(0 0, 100% 0, 0 100%);
                    right: 0;
                }

                /* circle */
                .timeline > ul li .date::after {
                    content: "";
                    position: absolute;
                    width: 2rem;
                    aspect-ratio: 1;
                    background: var(--bgColor);
                    border: 0.3rem solid var(--accent-color);
                    border-radius: 50%;
                    top: 50%;
                    transform: translate(50%, -50%);
                    right: calc(100% + var(--col-gap) + var(--line-w) / 2);
                }

            /* title descr */
            .timeline > ul li .title,
            .timeline > ul li .descr {
                background: var(--bgColorCard);
                position: relative;
                padding-inline: 1.5rem;
                /*z-index: 1;*/
            }

            .timeline > ul li .title {
                overflow: hidden;
                padding-block-start: 1.5rem;
                padding-block-end: 1rem;
                font-size: 1.2rem;
                font-weight: 500;
            }

            .timeline > ul li .descr {
                overflow: hidden;
                padding-block-end: 1.5rem;
                font-weight: 300;
                font-size: 1rem;
            }

                /* shadows */
                .timeline > ul li .title::before,
                .timeline > ul li .descr::before {
                    content: "";
                    position: absolute;
                    width: 90%;
                    height: 0.5rem;
                    background: rgba(0, 0, 0, 0.5);
                    left: 50%;
                    border-radius: 50%;
                    filter: blur(4px);
                    transform: translate(-50%, 50%);
                }

            .timeline > ul li .title::before {
                bottom: calc(100% + 0.125rem);
            }

            .timeline > ul li .descr::before {
                z-index: 0;
                bottom: -0.3rem;
            }

@media (min-width: 80rem) {
    .timeline > ul {
        grid-template-columns: 1fr var(--line-w) 1fr;
    }

        .timeline > ul::before {
            grid-column: 2;
        }

        .timeline > ul li:nth-child(odd) {
            grid-column: 1;
        }

        .timeline > ul li:nth-child(even) {
            grid-column: 3;
        }

        /* start second card */
        .timeline > ul li:nth-child(2) {
            grid-row: 2/4;
        }

        .timeline > ul li:nth-child(odd) .date::before {
            clip-path: polygon(0 0, 100% 0, 100% 100%);
            left: 0;
        }

        .timeline > ul li:nth-child(odd) .date::after {
            transform: translate(-50%, -50%);
            left: calc(100% + var(--col-gap) + var(--line-w) / 2);
        }

        .timeline > ul li:nth-child(odd) .date {
            border-radius: 0 calc(var(--dateH) / 2) calc(var(--dateH) / 2) 0;
        }
}

.credits {
    margin-top: 1rem;
    text-align: right;
}

    .credits a {
        color: var(--color);
    }