html {
    overflow-x: hidden;
}

.article-page-body {
    --home-bg: #f7f8fb;
    --home-surface: #ffffff;
    --home-text: #121722;
    --home-sub: #687386;
    --home-line: #e8edf4;
    --home-red: #d51f2b;
    --home-blue: #2f6fd6;
    --home-green: #31b36b;
    --home-shadow: 0 16px 36px rgba(20, 32, 50, 0.08);
    --home-soft-shadow: 0 8px 24px rgba(20, 32, 50, 0.06);
    min-height: 100vh;
    overflow-x: hidden;
    background: var(--bg-body);
}

.article-page {
    padding: 34px 20px 56px;
}

.article-shell {
    width: min(980px, 100%);
    margin: 0 auto;
}

.article-hero {
    margin-bottom: 22px;
}

.article-eyebrow {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    color: var(--text-sub);
    font-size: 12px;
    font-weight: 850;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.article-back-link {
    border-radius: 999px;
    text-decoration: none;
    transition: color 0.16s ease, background 0.16s ease, box-shadow 0.16s ease;
}

.article-back-link:hover,
.article-back-link:focus-visible {
    color: var(--home-red);
    background: rgba(213, 31, 43, 0.08);
    box-shadow: 0 0 0 6px rgba(213, 31, 43, 0.08);
    outline: none;
}

.article-hero h1 {
    margin: 12px 0 0;
    color: var(--text-main);
    font-size: clamp(34px, 4.5vw, 54px);
    line-height: 1.08;
}

.article-hero p {
    max-width: 760px;
    margin: 14px 0 0;
    color: var(--text-sub);
    font-size: 18px;
    line-height: 1.7;
}

.article-meta-strip {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 16px;
    margin-top: 16px;
    color: var(--text-sub);
    font-size: 14px;
    font-weight: 700;
}

.article-meta-strip span {
    padding: 8px 12px;
    border: 1px solid rgba(15, 48, 71, 0.12);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.78);
}

.article-content {
    padding: 26px;
    border: 1px solid rgba(229, 231, 235, 0.94);
    border-radius: 18px;
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
    color: var(--text-main);
}

.article-content > :first-child {
    margin-top: 0;
}

.article-content > :last-child {
    margin-bottom: 0;
}

.article-content h2,
.article-content h3,
.article-content h4 {
    margin: 1.45em 0 0.55em;
    color: var(--text-main);
    line-height: 1.25;
}

.article-content h2 {
    font-size: 28px;
}

.article-content h3 {
    font-size: 23px;
}

.article-content p,
.article-content ul,
.article-content ol,
.article-content blockquote,
.article-content table,
.article-embed-card,
.article-embed-cluster,
.article-question-card {
    margin: 0 0 18px;
}

.article-content ul,
.article-content ol {
    padding-left: 1.35em;
    list-style-position: outside;
}

.article-content li {
    padding-left: 0.2em;
}

.article-content a {
    color: var(--primary-color);
    font-weight: 750;
}

.article-content img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
}

.article-content figure {
    margin: 24px auto;
    text-align: center;
}

.article-content figure img,
.article-content p > img:only-child {
    display: block;
    margin-right: auto;
    margin-left: auto;
}

.article-content figcaption {
    margin-top: 8px;
    color: var(--text-sub);
    font-size: 14px;
    font-style: normal;
    line-height: 1.5;
    text-align: center;
}

.article-content th,
.article-content td {
    border-color: var(--border-color);
}

.article-embed-cluster {
    padding: 14px;
    border: 1px solid rgba(15, 48, 71, 0.12);
    border-radius: 16px;
    background: #f8fafc;
}

.article-embed-cluster-head {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 8px 12px;
    margin-bottom: 12px;
}

.article-embed-cluster-head span {
    color: var(--text-main);
    font-size: 14px;
    font-weight: 850;
}

.article-embed-cluster-head em {
    color: var(--text-sub);
    font-size: 12px;
    font-style: normal;
    font-weight: 750;
}

.article-embed-grid {
    gap: 12px;
    align-items: flex-start;
}

.article-embed-mosaic {
    display: grid;
    gap: 12px;
}

.article-embed-mosaic-row {
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(210px, 0.75fr);
    gap: 12px;
    align-items: start;
}

.article-embed-mosaic-main,
.article-embed-mosaic-stack {
    min-width: 0;
}

.article-embed-mosaic-stack {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    align-content: start;
}

.article-embed-mosaic-stack-full {
    grid-template-columns: repeat(auto-fit, minmax(205px, 1fr));
}

.article-embed-cluster-mosaic .article-embed-card.home-learning-card {
    width: 100%;
    min-width: 0;
    flex-basis: auto;
}

.article-content .article-embed-card.home-learning-card {
    flex-basis: 230px;
    align-self: flex-start;
    color: inherit;
}

.article-content .article-embed-feature.home-learning-card,
.article-content .article-embed-wide.home-learning-card {
    flex-basis: 300px;
}

.article-content .article-embed-mini.home-learning-card,
.article-content .article-embed-compact.home-learning-card {
    flex-basis: 205px;
}

.article-content > .article-embed-card.home-learning-card {
    width: min(360px, 100%);
    margin-bottom: 18px;
}

.article-content > .article-embed-wide.home-learning-card,
.article-content > .article-embed-feature.home-learning-card {
    width: 100%;
}

.article-content .article-embed-card .home-learning-body {
    gap: 8px;
    padding: 10px;
    align-content: start;
}

.article-page-body .article-content .article-embed-card.home-learning-card .home-learning-tags {
    flex-wrap: nowrap !important;
    height: 24px;
    max-height: 24px;
    overflow: hidden !important;
    white-space: nowrap;
}

.article-page-body .article-content .article-embed-card.home-learning-card .home-learning-tags span {
    max-width: 96px;
    overflow: hidden;
    flex: 0 1 auto;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.article-content .article-embed-card .home-learning-cover {
    width: 100%;
    aspect-ratio: 16 / 9;
    min-height: 0;
}

.article-content .article-embed-card .home-learning-cover img {
    display: block;
    width: 100%;
    height: 100%;
    border-radius: 0;
    object-fit: contain;
    object-position: center;
}

.article-page-body .article-content .article-embed-card.home-learning-card .home-learning-head > strong,
.article-page-body .article-content .article-embed-card.home-learning-card .home-learning-body > strong {
    display: -webkit-box !important;
    min-height: 34px;
    height: 34px;
    max-height: 34px;
    overflow: hidden !important;
    font-size: 13px;
    line-height: 17px;
    text-overflow: ellipsis;
    word-break: normal;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}

.article-page-body .article-content .article-embed-card.home-learning-card .article-embed-summary {
    display: -webkit-box !important;
    order: 3;
    min-height: 34px;
    max-height: 34px;
    overflow: hidden !important;
    color: var(--text-sub);
    font-size: 12px;
    font-weight: 600;
    line-height: 1.4;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}

.article-content .article-embed-mini .article-embed-summary,
.article-content .article-embed-compact .article-embed-summary {
    display: none;
}

.article-content .article-embed-card .home-learning-action {
    margin-top: 0;
}

.article-content .article-embed-inline.home-learning-card {
    display: inline-grid;
    width: min(260px, 100%);
    margin: 0 8px 12px 0;
    vertical-align: middle;
}

.article-content .article-question-card {
    box-shadow: var(--home-soft-shadow);
}

.article-content .article-question-card .exam-question-stage {
    padding: 20px 22px 0;
}

.article-content .article-question-card .exam-question-content {
    font-size: 18px;
}

.article-content .article-question-option {
    position: relative;
}

.article-content .article-question-input {
    position: absolute;
    inline-size: 1px;
    block-size: 1px;
    margin: 0;
    opacity: 0;
    pointer-events: none;
}

.article-content .article-question-binary-controls {
    display: inline-flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: flex-end;
    align-self: center;
}

.article-content .article-question-binary-controls label {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    min-height: 34px;
    padding: 0 10px;
    border: 1px solid var(--border-color);
    border-radius: 999px;
    background: var(--bg-card);
    font-size: 14px;
    font-weight: 750;
    white-space: nowrap;
}

.article-content .article-question-option-binary {
    grid-template-columns: 26px 34px minmax(0, 1fr) auto;
}

.article-content .article-question-fill {
    display: grid;
    gap: 8px;
    margin-top: 18px;
    font-weight: 800;
}

.article-content .article-question-fill input,
.article-content .article-question-fill textarea {
    width: 100%;
    border: 1px solid rgba(148, 163, 184, 0.5);
    border-radius: 16px;
    padding: 12px 14px;
    color: var(--text-main);
    font: inherit;
    line-height: 1.65;
    resize: vertical;
}

.article-content .article-question-actions {
    justify-content: flex-start;
}

.article-content .article-question-actions button:disabled {
    opacity: 0.55;
    cursor: wait;
}

.article-content .article-question-result {
    color: var(--text-sub);
    font-size: 14px;
    font-weight: 800;
}

.article-content .article-question-result[data-state="correct"] {
    color: #047857;
}

.article-content .article-question-result[data-state="wrong"],
.article-content .article-question-result[data-state="error"] {
    color: var(--primary-color);
}

.article-content .article-question-solution {
    margin: 0 22px 22px;
    padding: 14px 16px;
}

.article-content .article-question-solution[hidden] {
    display: none;
}

.article-content .article-question-solution-title {
    display: block;
    margin-bottom: 8px;
    color: var(--text-main);
    font-weight: 850;
}

.article-question-option-text > :first-child,
.article-question-content > :first-child,
.article-question-solution .cdq-rich > :first-child {
    margin-top: 0;
}

.article-question-option-text > :last-child,
.article-question-content > :last-child,
.article-question-solution .cdq-rich > :last-child {
    margin-bottom: 0;
}

.article-post-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 18px;
}

.article-post-nav a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    padding: 0 16px;
    border-radius: 999px;
    border: 1px solid rgba(198, 58, 50, 0.18);
    background: rgba(198, 58, 50, 0.06);
    color: var(--primary-color);
    font-size: 14px;
    font-weight: 800;
    text-decoration: none;
}

.article-post-nav a:hover,
.article-post-nav a:focus-visible {
    background: rgba(198, 58, 50, 0.12);
    outline: none;
}

.article-related {
    margin-top: 22px;
    padding: 20px;
    border: 1px solid rgba(15, 48, 71, 0.1);
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.78);
    box-shadow: var(--shadow-sm);
}

.article-related-head {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 14px;
}

.article-related-head h2 {
    margin: 0;
    color: var(--text-main);
    font-size: 20px;
    line-height: 1.3;
}

.article-related-head a {
    color: var(--primary-color);
    font-size: 13px;
    font-weight: 850;
    text-decoration: none;
}

.article-related-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.article-related-card {
    display: grid;
    align-content: start;
    gap: 7px;
    min-height: 150px;
    padding: 14px;
    border: 1px solid rgba(15, 48, 71, 0.1);
    border-radius: 12px;
    background: #fff;
    color: var(--text-main);
    text-decoration: none;
}

.article-related-card:hover,
.article-related-card:focus-visible {
    border-color: rgba(198, 58, 50, 0.32);
    outline: none;
}

.article-related-card span {
    color: var(--primary-color);
    font-size: 11px;
    font-weight: 850;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.article-related-card strong {
    display: -webkit-box;
    overflow: hidden;
    font-size: 15px;
    line-height: 1.35;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 3;
}

.article-related-card em {
    display: -webkit-box;
    overflow: hidden;
    color: var(--text-sub);
    font-size: 13px;
    font-style: normal;
    font-weight: 600;
    line-height: 1.45;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 3;
}

.article-list {
    display: grid;
    gap: 24px;
}

.article-index-tools {
    display: grid;
    gap: 14px;
    margin-bottom: 20px;
}

.article-search {
    display: grid;
    gap: 8px;
    color: var(--text-sub);
    font-size: 13px;
    font-weight: 850;
}

.article-search input {
    min-height: 46px;
    padding: 0 14px;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    background: var(--bg-card);
    color: var(--text-main);
    font: inherit;
}

.article-type-filter {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.article-type-filter button {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 38px;
    padding: 0 12px;
    border: 1px solid rgba(15, 48, 71, 0.12);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.82);
    color: var(--text-sub);
    cursor: pointer;
    font: inherit;
    font-size: 13px;
    font-weight: 850;
    transition: border-color 0.16s ease, background 0.16s ease, color 0.16s ease, box-shadow 0.16s ease;
}

.article-type-filter button:hover,
.article-type-filter button:focus-visible {
    border-color: rgba(198, 58, 50, 0.32);
    color: var(--home-red);
    outline: none;
}

.article-type-filter button.is-active {
    border-color: rgba(213, 31, 43, 0.28);
    background: rgba(213, 31, 43, 0.08);
    color: var(--home-red);
    box-shadow: 0 8px 18px rgba(213, 31, 43, 0.08);
}

.article-type-filter button em {
    min-width: 24px;
    padding: 3px 7px;
    border-radius: 999px;
    background: rgba(15, 48, 71, 0.08);
    color: inherit;
    font-size: 12px;
    font-style: normal;
    text-align: center;
}

.article-type-section {
    display: grid;
    gap: 12px;
}

.article-type-section-head {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 12px;
    padding-top: 2px;
}

.article-type-section-head h2 {
    margin: 0;
    color: var(--text-main);
    font-size: 22px;
    line-height: 1.25;
}

.article-type-section-head span {
    color: var(--text-sub);
    font-size: 13px;
    font-weight: 850;
    white-space: nowrap;
}

.article-type-grid {
    display: grid;
    gap: 14px;
}

.article-list-card {
    display: grid;
    grid-template-columns: minmax(132px, 22%) minmax(0, 1fr);
    gap: 16px;
    align-items: stretch;
    padding: 12px;
    border: 1px solid rgba(229, 231, 235, 0.94);
    border-radius: 14px;
    background: var(--bg-card);
    color: var(--text-main);
    text-decoration: none;
    box-shadow: var(--shadow-sm);
}

.article-list-card-thumb {
    display: block;
    overflow: hidden;
    min-height: 118px;
    border-radius: 10px;
    background: rgba(15, 48, 71, 0.06);
}

.article-list-card-thumb img {
    display: block;
    width: 100%;
    height: 100%;
    min-height: 118px;
    object-fit: cover;
}

.article-list-card-body {
    display: grid;
    align-content: center;
    gap: 6px;
    min-width: 0;
    padding: 6px 8px 6px 0;
}

.article-list-card:hover,
.article-list-card:focus-visible {
    border-color: rgba(198, 58, 50, 0.32);
    outline: none;
    box-shadow: var(--shadow-md);
}

.article-list-card-type {
    color: var(--text-sub);
    font-size: 12px;
    font-weight: 850;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.article-list-card strong {
    font-size: 21px;
    line-height: 1.35;
}

.article-list-card em {
    color: var(--text-sub);
    font-style: normal;
    line-height: 1.65;
}

.article-toc {
    margin: 0 0 18px;
    padding: 16px 18px;
    border: 1px solid rgba(15, 48, 71, 0.12);
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.72);
}

.article-toc-title {
    color: var(--text-sub);
    font-size: 12px;
    font-weight: 850;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.article-toc ol {
    display: grid;
    gap: 7px;
    margin: 10px 0 0;
    padding-left: 20px;
}

.article-toc li.is-h3 {
    margin-left: 18px;
}

.article-toc a {
    color: var(--secondary-color);
    font-weight: 750;
    text-decoration: none;
}

@media (max-width: 640px) {
    .article-list-card {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .article-list-card-thumb,
    .article-list-card-thumb img {
        min-height: 170px;
    }

    .article-list-card-body {
        padding: 2px 4px 6px;
    }

    .article-meta-strip {
        gap: 8px;
    }

    .article-meta-strip span,
    .article-post-nav a {
        width: 100%;
        justify-content: flex-start;
    }
}

.article-faq {
    margin-top: 28px;
}

.article-faq details {
    border-top: 1px solid var(--border-color);
    padding: 12px 0;
}

.article-faq summary {
    cursor: pointer;
    font-weight: 850;
}

.article-faq-answer {
    margin-top: 8px;
    color: var(--text-main);
}

.article-faq-answer > :first-child {
    margin-top: 0;
}

.article-faq-answer > :last-child {
    margin-bottom: 0;
}

body.dark-mode.article-page-body {
    --article-dark-bg: var(--bg-body);
    --article-dark-surface: var(--bg-card);
    --article-dark-surface-soft: var(--bg-elevated);
    --article-dark-border: var(--border-color);
    --article-dark-border-strong: #565759;
    --article-dark-text: var(--text-main);
    --article-dark-muted: var(--text-sub);
    --article-dark-soft: var(--text-sub);
    --article-dark-link: #f08a82;
    --article-dark-red: #fca5a5;
    background: var(--article-dark-bg);
}

body.dark-mode.article-page-body .article-eyebrow,
body.dark-mode.article-page-body .article-hero p,
body.dark-mode.article-page-body .article-meta-strip,
body.dark-mode.article-page-body .article-related-card em,
body.dark-mode.article-page-body .article-list-card em,
body.dark-mode.article-page-body .article-content figcaption,
body.dark-mode.article-page-body .article-faq-answer {
    color: var(--article-dark-muted);
}

body.dark-mode.article-page-body .article-hero h1,
body.dark-mode.article-page-body .article-content,
body.dark-mode.article-page-body .article-content h2,
body.dark-mode.article-page-body .article-content h3,
body.dark-mode.article-page-body .article-content h4,
body.dark-mode.article-page-body .article-related-head h2,
body.dark-mode.article-page-body .article-related-card strong,
body.dark-mode.article-page-body .article-list-card strong,
body.dark-mode.article-page-body .article-type-section-head h2,
body.dark-mode.article-page-body .article-faq summary {
    color: var(--article-dark-text);
}

body.dark-mode.article-page-body .article-content a,
body.dark-mode.article-page-body .article-toc a {
    color: var(--article-dark-link);
}

body.dark-mode.article-page-body .article-content,
body.dark-mode.article-page-body .article-toc,
body.dark-mode.article-page-body .article-related,
body.dark-mode.article-page-body .article-related-card,
body.dark-mode.article-page-body .article-list-card,
body.dark-mode.article-page-body .article-search input {
    border-color: var(--article-dark-border);
    background: var(--article-dark-surface);
    color: var(--article-dark-text);
    box-shadow: none;
}

body.dark-mode.article-page-body .article-content {
    background: var(--article-dark-surface);
}

body.dark-mode.article-page-body .article-meta-strip span,
body.dark-mode.article-page-body .article-type-filter button,
body.dark-mode.article-page-body .article-post-nav a,
body.dark-mode.article-page-body .article-question-binary-controls label {
    border-color: var(--article-dark-border);
    background: var(--article-dark-surface-soft);
    color: var(--article-dark-muted);
}

body.dark-mode.article-page-body .article-meta-strip span {
    color: var(--article-dark-text);
}

body.dark-mode.article-page-body .article-toc-title,
body.dark-mode.article-page-body .article-related-card span,
body.dark-mode.article-page-body .article-list-card-type,
body.dark-mode.article-page-body .article-type-section-head span,
body.dark-mode.article-page-body .article-search {
    color: var(--article-dark-soft);
}

body.dark-mode.article-page-body .article-type-filter button:hover,
body.dark-mode.article-page-body .article-type-filter button:focus-visible,
body.dark-mode.article-page-body .article-type-filter button.is-active,
body.dark-mode.article-page-body .article-post-nav a:hover,
body.dark-mode.article-page-body .article-post-nav a:focus-visible,
body.dark-mode.article-page-body .article-back-link:hover,
body.dark-mode.article-page-body .article-back-link:focus-visible {
    border-color: rgba(230, 106, 97, 0.42);
    background: rgba(198, 58, 50, 0.16);
    color: var(--article-dark-link);
    box-shadow: 0 10px 26px rgba(0, 0, 0, 0.28);
}

body.dark-mode.article-page-body .article-type-filter button em {
    background: rgba(148, 163, 184, 0.14);
    color: inherit;
}

body.dark-mode.article-page-body .article-list-card:hover,
body.dark-mode.article-page-body .article-list-card:focus-visible,
body.dark-mode.article-page-body .article-related-card:hover,
body.dark-mode.article-page-body .article-related-card:focus-visible {
    border-color: rgba(230, 106, 97, 0.36);
    box-shadow: 0 16px 34px rgba(0, 0, 0, 0.34);
}

body.dark-mode.article-page-body .article-list-card-thumb,
body.dark-mode.article-page-body .article-content .article-embed-card .home-learning-cover {
    background: var(--article-dark-surface-soft);
}

body.dark-mode.article-page-body .article-content th,
body.dark-mode.article-page-body .article-content td,
body.dark-mode.article-page-body .article-faq details {
    border-color: var(--article-dark-border);
}

@media (max-width: 720px) {
    .article-page {
        padding: 22px 12px 42px;
    }

    .article-content {
        padding: 18px;
    }

    .article-related {
        padding: 16px;
    }

    .article-related-grid {
        grid-template-columns: 1fr;
    }

    .article-content .article-embed-card.home-learning-card,
    .article-content .article-embed-feature.home-learning-card,
    .article-content .article-embed-wide.home-learning-card,
    .article-content .article-embed-mini.home-learning-card,
    .article-content .article-embed-compact.home-learning-card {
        flex-basis: calc((100% - 10px) / 2);
    }

    .article-embed-grid {
        gap: 10px;
    }

    .article-embed-mosaic-row {
        grid-template-columns: 1fr;
    }

    .article-embed-mosaic-stack {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .article-content > .article-embed-card.home-learning-card {
        width: 100%;
    }

    .article-content .article-embed-card .article-embed-summary {
        display: none;
    }

    .article-content .article-question-option-binary {
        grid-template-columns: 26px 34px minmax(0, 1fr);
    }

    .article-content .article-question-binary-controls {
        grid-column: 3;
        justify-content: flex-start;
    }
}

@media (max-width: 420px) {
    .article-content .article-embed-card.home-learning-card,
    .article-content .article-embed-feature.home-learning-card,
    .article-content .article-embed-wide.home-learning-card,
    .article-content .article-embed-mini.home-learning-card,
    .article-content .article-embed-compact.home-learning-card {
        flex-basis: 100%;
    }

    .article-embed-mosaic-stack,
    .article-embed-mosaic-stack-full {
        grid-template-columns: 1fr;
    }
}