body {
    background: #fff;
}

.blog-index {
    /* Светлая типографика — как в article.css: боди ~10:1, вторичный
       текст ≥4.5:1 (WCAG AA) */
    --bi-blue: #045cf1;
    --bi-ink: #0b1b3b;
    --bi-text: #36415a;
    --bi-muted: #62718c;
    --bi-line: #dde5f1;
    --bi-soft: #f5f8fc;
    --bi-card: #fff;
    --bi-chip-line: #c8d8f1;
    /* Cloudflare-style dashed dividers: the dash length isn't controllable
       with border-style, so lines are drawn with repeating gradients */
    --bi-dash-x: repeating-linear-gradient(90deg, var(--bi-line) 0 7px, transparent 7px 18px);
    --bi-dash-y: repeating-linear-gradient(180deg, var(--bi-line) 0 7px, transparent 7px 18px);
    overflow: hidden;
    color: var(--bi-text);
}

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

.blog-index__container {
    width: 88%;
    max-width: 1280px;
    margin: 0 auto;
}

.blog-index__intro {
    position: relative;
    isolation: isolate;
    overflow: hidden;
    padding: 76px 0 68px;
    border-bottom: 1px solid var(--bi-line);
    background:
        radial-gradient(circle at 82% 18%, rgba(4, 92, 241, 0.1), transparent 30%),
        linear-gradient(135deg, #fff 0%, #f9fbff 58%, #f2f7ff 100%);
}

.blog-index__intro::before {
    position: absolute;
    z-index: -1;
    inset: 0;
    background-image:
        linear-gradient(rgba(11, 27, 59, 0.045) 1px, transparent 1px),
        linear-gradient(90deg, rgba(11, 27, 59, 0.045) 1px, transparent 1px);
    background-position: center;
    background-size: 42px 42px;
    content: "";
    mask-image: linear-gradient(90deg, transparent 2%, rgba(0, 0, 0, 0.16) 36%, #000 100%);
}

.blog-index__intro::after {
    position: absolute;
    z-index: -1;
    top: 24%;
    right: -8%;
    width: 48%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(4, 92, 241, 0.45), transparent);
    box-shadow:
        -110px 102px 0 rgba(4, 92, 241, 0.14),
        40px 210px 0 rgba(4, 92, 241, 0.1);
    content: "";
    transform: rotate(-14deg);
}

.blog-index__intro-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(390px, 0.85fr);
    gap: clamp(52px, 7vw, 100px);
    align-items: center;
}

.blog-index__eyebrow,
.blog-index__featured-label,
.blog-index__item-date {
    color: var(--bi-blue);
    font: 700 12px/18px "Inter", sans-serif;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.blog-index__intro h1 {
    max-width: 760px;
    margin: 10px 0 0;
    color: var(--bi-ink);
    font: 700 46px/56px "Onest", "Inter", sans-serif;
    letter-spacing: -0.6px;
}

.blog-index__lead {
    max-width: 650px;
    margin: 14px 0 0;
    font: 400 18px/30px "Inter", sans-serif;
}

.blog-index__filters {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 9px;
    margin-top: 13px;
}

.blog-index__filter-label {
    margin: 0;
    color: var(--bi-muted);
    font: 600 12px/18px "Inter", sans-serif;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.blog-index__filter-panel {
    padding: 25px;
    border: 1px solid rgba(200, 216, 241, 0.88);
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.82);
    box-shadow: 0 18px 48px rgba(23, 54, 105, 0.09);
    backdrop-filter: blur(12px);
}

.blog-index__filter {
    display: inline-flex;
    align-items: center;
    justify-content: space-between;
    min-height: 36px;
    padding: 7px 15px;
    border: 1px solid var(--bi-chip-line);
    border-radius: 7px;
    background: var(--bi-card);
    color: var(--bi-blue);
    font: 600 13px/20px "Inter", sans-serif;
    text-decoration: none;
}

.blog-index__filter > span {
    margin-left: 7px;
    color: var(--bi-muted);
    font-size: 11px;
}

.blog-index__filter--research {
    grid-column: 1 / -1;
}

.blog-index__filter.is-active {
    border-color: var(--bi-blue);
    background: var(--bi-blue);
    color: #fff;
}

.blog-index__filter.is-active > span {
    color: rgba(255, 255, 255, 0.76);
}

.blog-index__featured {
    background: var(--bi-soft);
}

.blog-index__featured-inner {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(340px, 0.85fr);
    gap: 72px;
    align-items:center;
    min-height: 380px;
    padding: 62px 0;
}

.blog-index__featured h2 {
    max-width: 760px;
    margin: 13px 0 0;
    color: var(--bi-ink);
    font: 700 40px/49px "Onest", "Inter", sans-serif;
    letter-spacing: -0.45px;
}

.blog-index__featured h2 a {
    color: inherit;
    text-decoration: none;
}

.blog-index__featured h2 a:hover {
    color: var(--bi-blue);
}

.blog-index__featured-copy p {
    margin: 0;
    font: 400 17px/29px "Inter", sans-serif;
}

.blog-index__meta {
    display: flex;
    flex-wrap: wrap;
    gap: 7px 17px;
    margin-top: 22px;
    color: var(--bi-muted);
    font: 400 13px/20px "Inter", sans-serif;
}

.blog-index__meta span + span::before {
    margin-right: 17px;
    content: "·";
}

.blog-index__read {
    display: inline-block;
    margin-top: 23px;
    color: var(--bi-blue);
    font: 600 14px/20px "Inter", sans-serif;
    text-decoration: none;
}

.blog-index__research {
    padding: 58px 0 64px;
    border-top: 1px solid var(--bi-line);
    border-bottom: 1px solid var(--bi-line);
}

.blog-index__section-head {
    display: flex;
    gap: 30px;
    align-items: end;
    justify-content: space-between;
    margin-bottom: 28px;
}

.blog-index__section-head h2 {
    margin: 8px 0 0;
    color: var(--bi-ink);
    font: 700 30px/38px "Onest", "Inter", sans-serif;
}

.blog-index__section-head > a {
    color: var(--bi-blue);
    font: 600 13px/20px "Inter", sans-serif;
    text-decoration: none;
}

.blog-index__research-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-top: 1px solid var(--bi-line);
    border-left: 1px solid var(--bi-line);
}

.blog-index__research-card {
    position: relative;
    display: flex;
    min-width: 0;
    min-height: 250px;
    flex-direction: column;
    padding: 27px 28px 31px;
    border-right: 1px solid var(--bi-line);
    border-bottom: 1px solid var(--bi-line);
    background: var(--bi-card);
    color: var(--bi-text);
    text-decoration: none;
    transition: background 160ms ease, transform 160ms ease;
}

.blog-index__research-card:hover {
    background: var(--bi-soft);
    transform: translateY(-3px);
}

.blog-index__research-card-meta {
    color: var(--bi-blue);
    font: 700 11px/17px "Inter", sans-serif;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.blog-index__research-card strong {
    margin-top: 18px;
    color: var(--bi-ink);
    font: 700 20px/28px "Onest", "Inter", sans-serif;
}

.blog-index__research-card > span:not(.blog-index__research-card-meta) {
    margin-top: 12px;
    font: 400 13.5px/22px "Inter", sans-serif;
}

.blog-index__research-card > b {
    position: absolute;
    right: 24px;
    bottom: 20px;
    color: var(--bi-blue);
    font: 600 17px/20px "Inter", sans-serif;
}

.blog-index__latest {
    padding: 62px 0 88px;
}

.blog-index__latest h2 {
    margin: 0 0 28px;
    color: var(--bi-ink);
    font: 700 30px/38px "Onest", "Inter", sans-serif;
}

.blog-index__grid-wrap {
    position: relative;
}

.blog-index__grid-wrap::before {
    position: absolute;
    top: 0;
    left: 50%;
    width: 100vw;
    height: 1px;
    background: var(--bi-dash-x);
    content: "";
    transform: translateX(-50%);
}

.blog-index__grid {
    position: relative;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.blog-index__grid::after {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 50%;
    width: 1px;
    background: var(--bi-dash-y);
    content: "";
}

.blog-index__item {
    position: relative;
    min-width: 0;
    padding: 39px 42px 43px 0;
}

.blog-index__item:nth-child(even) {
    padding-right: 0;
    padding-left: 42px;
}

.blog-index__item:nth-child(odd)::after {
    /* line under the whole row: the item is the left column, so its own
       center isn't the viewport center — anchor to the viewport left edge
       instead (item width = 100%, half the container) */
    position: absolute;
    right: auto;
    bottom: 0;
    left: calc(100% - 50vw);
    width: 100vw;
    height: 1px;
    background: var(--bi-dash-x);
    content: "";
}

.blog-index__item h3 {
    margin: 11px 0 0;
    color: var(--bi-ink);
    font: 700 21px/29px "Onest", "Inter", sans-serif;
}

.blog-index__item-top {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 12px;
    align-items: center;
    justify-content: space-between;
}

.blog-index__research-badge {
    display: inline-flex;
    align-items: center;
    min-height: 24px;
    padding: 3px 8px;
    border: 1px solid var(--bi-chip-line);
    border-radius: 999px;
    color: var(--bi-blue);
    font: 600 11px/16px "Inter", sans-serif;
}

.blog-index__item h3 a {
    color: inherit;
    text-decoration: none;
}

.blog-index__item h3 a:hover {
    color: var(--bi-blue);
}

.blog-index__item p {
    max-width: 520px;
    margin: 12px 0 0;
    font: 400 14.5px/24px "Inter", sans-serif;
}

.blog-index__item-meta {
    margin-top: 17px;
    color: var(--bi-muted);
    font: 400 12.5px/19px "Inter", sans-serif;
}

.blog-index__pagination {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-top: 42px;
}

.blog-index__pagination a,
.blog-index__pagination span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 34px;
    height: 34px;
    padding: 0 10px;
    border-radius: 6px;
    color: var(--bi-blue);
    font: 600 13px/18px "Inter", sans-serif;
    text-decoration: none;
}

.blog-index__pagination .is-current {
    background: var(--bi-blue);
    color: #fff;
}

@media (max-width: 900px) {
    .blog-index__intro-grid {
        grid-template-columns: 1fr;
        gap: 38px;
    }

    .blog-index__filter-panel {
        max-width: 620px;
    }

    .blog-index__intro h1 {
        font-size: 38px;
        line-height: 47px;
    }

    .blog-index__featured-inner {
        grid-template-columns: 1fr;
        gap: 28px;
        min-height: 0;
    }

    .blog-index__featured h2 {
        font-size: 34px;
        line-height: 43px;
    }

    .blog-index__research-grid {
        grid-template-columns: 1fr;
    }

    .blog-index__research-card {
        min-height: 0;
        padding-bottom: 46px;
    }
}

@media (max-width: 700px) {
    .blog-index__container {
        width: calc(100% - 32px);
    }

    .blog-index__intro {
        padding: 50px 0 42px;
    }

    .blog-index__intro h1 {
        font-size: 31px;
        line-height: 39px;
    }

    .blog-index__lead {
        font-size: 16px;
        line-height: 27px;
    }

    .blog-index__filter-panel {
        padding: 19px;
    }

    .blog-index__featured-inner {
        padding: 42px 0;
    }

    .blog-index__featured h2 {
        font-size: 29px;
        line-height: 37px;
    }

    .blog-index__research {
        padding: 42px 0 48px;
    }

    .blog-index__section-head {
        display: block;
    }

    .blog-index__section-head > a {
        display: inline-block;
        margin-top: 14px;
    }

    .blog-index__grid {
        grid-template-columns: 1fr;
    }

    .blog-index__grid::after {
        display: none;
    }

    .blog-index__item,
    .blog-index__item:nth-child(even) {
        padding: 31px 0 34px;
    }

    .blog-index__item:nth-child(odd)::after,
    .blog-index__item:nth-child(even)::after {
        /* single column: the item spans the container, its center matches
           the viewport center again */
        position: absolute;
        bottom: 0;
        left: 50%;
        display: block;
        width: 100vw;
        height: 1px;
        background: var(--bi-dash-x);
        content: "";
        transform: translateX(-50%);
    }
}

@media (max-width: 460px) {
    .blog-index__filters {
        grid-template-columns: 1fr;
    }

    .blog-index__filter--research {
        grid-column: auto;
    }
}

/* ---------- Тёмная тема (пилот): включается data-theme="dark" на <html>,
   см. css/blog/dark.css (фон страницы, шапка, кнопка-переключатель) ---------- */

[data-theme="dark"] .blog-index {
    /* База — графит футера v2 (#10151f), без синевы; типографика и акцент —
       как в article.css: заголовки ≈ 87% белого, текст ~70%, синий
       осветлён и обесцвечен */
    --bi-blue: #7fa8f0;
    --bi-ink: #dde3ec;
    --bi-text: #a5b0c2;
    --bi-muted: #7d8ba0;
    --bi-line: #232b3a;
    --bi-soft: #171d29;
    --bi-card: #171d29;
    --bi-chip-line: #2b3445;
}

[data-theme="dark"] .blog-index__intro {
    background:
        radial-gradient(circle at 82% 18%, rgba(70, 120, 210, 0.16), transparent 30%),
        linear-gradient(135deg, #10151f 0%, #121925 58%, #151e2d 100%);
}

[data-theme="dark"] .blog-index__intro::before {
    background-image:
        linear-gradient(rgba(127, 168, 240, 0.07) 1px, transparent 1px),
        linear-gradient(90deg, rgba(127, 168, 240, 0.07) 1px, transparent 1px);
}

[data-theme="dark"] .blog-index__filter-panel {
    border-color: rgba(43, 52, 69, 0.94);
    background: rgba(23, 29, 41, 0.84);
    box-shadow: 0 18px 48px rgba(0, 0, 0, 0.2);
}

/* Заливка активного фильтра и текущей страницы пагинации: осветлённый
   акцент не держит белый текст — свой насыщенный синий */
[data-theme="dark"] .blog-index__filter.is-active,
[data-theme="dark"] .blog-index__pagination .is-current {
    border-color: #2563eb;
    background: #2563eb;
    color: #fff;
}