html:has([data-case-study-shell]),
body:has([data-case-study-shell]) {
    overflow-x: clip;
}

.case-study-shell,
.case-study-shell *,
.case-study-shell *::before,
.case-study-shell *::after {
    box-sizing: border-box;
    min-inline-size: 0;
}

    .case-study-shell {
        /* A case study can override these through its data-case-study-id hook. */
        --case-reading-width: 46rem;
        --case-wide-width: 72rem;
        --case-hero-ratio: 16 / 10;
        --case-visual-hero-ratio: 16 / 7;
        container: case-study / inline-size;
        display: grid;
        gap: clamp(1.25rem, 3vi, 2.25rem);
        padding-inline: clamp(1rem, 3vi, 2rem);
        overflow-wrap: anywhere;
    }

    .breadcrumb {
        margin-block-end: 0;
    }

    .case-study-toolbar {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        padding-block: 0.7rem;
        border-block: 1px solid var(--color-border);
    }

    .case-study-toolbar__label {
        margin: 0;
        color: var(--color-text-muted);
        font-family: var(--font-mono);
        font-size: 0.72rem;
        letter-spacing: 0.08em;
        text-transform: uppercase;
    }

    .case-study-switch {
        display: inline-grid;
        grid-template-columns: repeat(2, minmax(4.75rem, 1fr));
        border: 1px solid var(--color-border);
    }

    .case-study-switch__button {
        min-block-size: 2.25rem;
        padding: 0.45rem 0.75rem;
        border: 0;
        border-inline-start: 1px solid var(--color-border);
        background: transparent;
        color: var(--color-text-muted);
        font: 500 0.76rem/1 var(--font-mono);
        letter-spacing: 0.06em;
        text-transform: uppercase;
        cursor: pointer;
    }

    .case-study-switch__button:first-child {
        border-inline-start: 0;
    }

    .case-study-switch__button:hover {
        color: var(--color-text);
    }

    .case-study-switch__button[aria-pressed="true"] {
        background: var(--color-accent);
        color: #071212;
    }

    .case-study-switch__button:focus-visible {
        position: relative;
        z-index: 1;
        outline: 2px solid var(--color-accent-bright);
        outline-offset: 3px;
    }

    .project-page {
        display: grid;
        gap: clamp(2rem, 5vi, 4.5rem);
        inline-size: 100%;
    }

    .project-page img,
    .project-page svg,
    .project-page video,
    .project-page canvas {
        display: block;
        max-inline-size: 100%;
        block-size: auto;
    }

    .project-header {
        display: grid;
        gap: clamp(1.25rem, 3vi, 2rem);
        padding-block-end: clamp(1.5rem, 4vi, 3rem);
        border-block-end: 1px solid var(--color-border);
    }

    .project-header__grid,
    .project-section__split,
    .project-section__split--wide,
    .comparison-box {
        display: grid;
        grid-template-columns: minmax(0, 1fr);
        gap: clamp(1rem, 3vi, 2rem);
    }

    .project-header__title {
        margin: 0;
        font-size: clamp(2.25rem, 10vi, 4.75rem);
        line-height: 0.98;
        letter-spacing: 0;
    }

    .project-header__summary {
        max-inline-size: 48rem;
        margin: 0.85rem 0 0;
        color: var(--color-text-muted);
        font-size: clamp(1rem, 1.5vi, 1.12rem);
        line-height: 1.75;
    }

    .project-header__hero-container {
        inline-size: 100%;
        max-inline-size: 100%;
        contain: inline-size;
    }

    .project-header__hero {
        position: static;
        inline-size: 100%;
        max-inline-size: 100%;
        min-block-size: 0;
        aspect-ratio: var(--case-hero-ratio);
        border: 1px solid var(--color-border);
        background: var(--color-bg-secondary);
        object-fit: cover;
        overflow: visible;
    }

    .project-header__meta {
        display: grid;
        grid-template-columns: minmax(0, 1fr);
        gap: 1rem;
        margin: 0;
    }

    .project-fact,
    .project-meta {
        margin: 0;
        padding-block-start: 0.75rem;
        border-block-start: 1px solid var(--color-border);
    }

    .project-fact dt,
    .project-meta dt {
        margin-block-end: 0.25rem;
        color: var(--color-accent);
        font: 500 0.72rem/1.4 var(--font-mono);
        letter-spacing: 0.08em;
        text-transform: uppercase;
    }

    .project-fact dd,
    .project-meta dd {
        margin: 0;
        line-height: 1.5;
    }

    .project-provenance {
        padding: 0.9rem 1rem;
        border: 1px solid var(--color-border);
        background: color-mix(in srgb, var(--color-bg-secondary) 72%, transparent);
        font-size: 0.88rem;
        line-height: 1.55;
    }

    .project-provenance strong {
        display: block;
        margin-block-end: 0.25rem;
        font-size: 0.75rem;
        letter-spacing: 0.08em;
        text-transform: uppercase;
    }

    .project-toc {
        display: flex;
        flex-wrap: nowrap;
        gap: 0.55rem 1rem;
        margin-block-start: 1.25rem;
        padding-block: 0.9rem;
        border-block: 1px solid var(--color-border);
        overflow-x: auto;
        overflow-y: hidden;
        overscroll-behavior-inline: contain;
        scrollbar-width: thin;
        -webkit-overflow-scrolling: touch;
    }

    .project-toc a {
        flex: 0 0 auto;
        min-inline-size: max-content;
        color: var(--color-text-muted);
        line-height: 1.5;
        text-decoration: none;
        white-space: nowrap;
    }

    .case-study-shell .sticky-nav__list > li,
    .case-study-shell .sticky-nav__link {
        flex: 0 0 auto;
        min-inline-size: max-content;
    }

    .case-study-shell .sticky-nav__link {
        white-space: nowrap;
    }

    .project-toc a:hover,
    .project-toc a:focus-visible,
    .project-nav a:hover,
    .related-link:hover {
        color: var(--color-accent-bright);
    }

    .project-section {
        display: grid;
        gap: 1rem;
        inline-size: 100%;
        padding-block-start: clamp(1.5rem, 4vi, 3rem);
        border-block-start: 1px solid var(--color-border);
        scroll-margin-block-start: 6rem;
    }

    .project-section h2 {
        margin: 0;
        font-size: clamp(1.35rem, 3vi, 2rem);
        line-height: 1.2;
        letter-spacing: 0;
    }

    .project-section h3 {
        letter-spacing: 0;
    }

    .project-section p,
    .project-section li,
    .project-note-item span,
    .related-link-item p,
    .screenshot-caption {
        color: var(--color-text-muted);
        line-height: 1.75;
    }

    .project-section p,
    .project-section ul,
    .project-section ol {
        margin-block-start: 0;
    }

    .project-section ul,
    .project-section ol {
        padding-inline-start: 1.25rem;
    }

    .project-note-list,
    .decision-list,
    .feature-list,
    .challenge-list,
    .link-list,
    .screenshot-list,
    .tradeoff-list,
    .related-link-list {
        display: grid;
        gap: 1rem;
    }

    .project-note-item,
    .decision-item,
    .challenge-item,
    .feature-item,
    .result-item,
    .retrospective-item,
    .tradeoff-item,
    .related-link-item {
        padding-block-start: 1rem;
        border-block-start: 1px solid var(--color-border);
    }

    :is(.project-note-item, .decision-item, .challenge-item, .feature-item, .result-item, .retrospective-item, .tradeoff-item, .related-link-item):first-child {
        padding-block-start: 0;
        border-block-start: 0;
    }

    :is(.decision-item, .challenge-item, .feature-item, .result-item, .retrospective-item, .tradeoff-item) h3,
    .comparison-column h3 {
        margin: 0 0 0.4rem;
        font-size: 1rem;
    }

    .project-diagram,
    .comparison-box {
        padding: clamp(0.8rem, 2vi, 1.25rem);
        border: 1px solid var(--color-border);
        background: color-mix(in srgb, var(--color-bg-secondary) 75%, transparent);
        overflow: visible;
    }

    .project-diagram pre {
        position: relative;
        z-index: 1;
        max-inline-size: 100%;
        margin: 0;
        padding: 0;
        border: 0;
        background: transparent;
        color: var(--color-text);
        font: 400 clamp(0.68rem, 1.7vi, 0.8rem)/1.65 var(--font-mono);
        white-space: pre-wrap;
        overflow-wrap: anywhere;
    }

    .screenshot-frame {
        inline-size: 100%;
        min-block-size: clamp(12rem, 45vi, 28rem);
        border: 1px solid var(--color-border);
        background: var(--color-bg-secondary);
    }

    .screenshot-caption,
    .placeholder-note {
        margin: 0.5rem 0 0;
        color: var(--color-text-muted);
        font-size: 0.86rem;
        font-style: italic;
    }

    .visual-placeholder {
        inline-size: 100%;
        margin: 0.5rem 0 1rem;
    }

    .visual-placeholder[hidden] {
        display: none;
    }

    .visual-placeholder img {
        inline-size: 100%;
        aspect-ratio: 3 / 2;
        border: 1px solid var(--color-border);
        background: var(--color-bg-secondary);
        object-fit: cover;
    }

    figure.project-diagram {
        inline-size: 100%;
        margin: 1rem 0 1.5rem;
    }

    figure.project-diagram img {
        inline-size: 100%;
        height: auto;
        border: 1px solid var(--color-border);
        border-radius: 4px;
        background: var(--color-bg-secondary);
    }

    .project-nav {
        display: grid;
        gap: 0.75rem;
        padding-block-start: 1.5rem;
        border-block-start: 1px solid var(--color-border);
    }

    .project-nav a,
    .project-nav span,
    .related-link {
        font-family: var(--font-mono);
        font-size: 0.8rem;
    }

    /* V1: a focused article with one continuous reading column. */
    [data-case-study-mode="article"] .project-page {
        max-inline-size: var(--case-reading-width);
        margin-inline: auto;
        gap: clamp(2.5rem, 6vi, 4.5rem);
    }

    [data-case-study-mode="article"] :is(.project-header__grid, .project-section__split, .project-section__split--wide, .comparison-box) {
        grid-template-columns: minmax(0, 1fr);
    }

    [data-case-study-mode="article"] .project-header__hero-container {
        margin-block-start: 0.5rem;
    }

    [data-case-study-mode="article"] .project-header__meta {
        grid-template-columns: repeat(auto-fit, minmax(min(100%, 13rem), 1fr));
    }

    [data-case-study-mode="article"] .project-section :is(p, li) {
        font-size: 1.02rem;
    }

    /* V3: an image-led editorial composition with wide supporting evidence. */
    [data-case-study-mode="visual"] {
        scroll-behavior: smooth;
    }

    [data-case-study-mode="visual"] .case-study-shell {
        position: relative;
        isolation: isolate;
        padding-block: clamp(0.5rem, 2vi, 1.5rem) clamp(3rem, 7vi, 6rem);
    }

    [data-case-study-mode="visual"] .case-study-shell::before {
        content: "";
        position: absolute;
        z-index: -1;
        inset-block: 0;
        inset-inline-start: 50%;
        inline-size: 100vw;
        transform: translateX(-50%);
        background-color: color-mix(in srgb, var(--color-bg) 88%, var(--color-bg-secondary) 12%);
        background-image:
            linear-gradient(to bottom, color-mix(in srgb, var(--color-surface) 36%, transparent), transparent 24rem),
            linear-gradient(to right, color-mix(in srgb, var(--color-border) 18%, transparent) 1px, transparent 1px);
        background-size: auto, clamp(4rem, 9vw, 8rem) 100%;
        pointer-events: none;
    }

    [data-case-study-mode="visual"] .project-page {
        max-inline-size: var(--case-wide-width);
        margin-inline: auto;
        gap: clamp(3.5rem, 8vi, 7rem);
    }

    [data-case-study-mode="visual"] .project-header {
        gap: clamp(1.5rem, 4vi, 3rem);
        padding-block-end: clamp(2.5rem, 6vi, 5rem);
        border-block-end-color: color-mix(in srgb, var(--color-border) 64%, transparent);
    }

    [data-case-study-mode="visual"] .project-header__summary {
        max-inline-size: 62ch;
    }

    [data-case-study-mode="visual"] .project-header__hero {
        max-block-size: min(68vh, 42rem);
    }

    [data-case-study-mode="visual"] .project-section {
        position: relative;
        gap: clamp(1.25rem, 3vi, 2rem);
        padding-block-start: clamp(2rem, 5vi, 4rem);
        border-block-start: 0;
    }

    [data-case-study-mode="visual"] .project-section::before {
        content: "";
        position: absolute;
        inset-block-start: 0;
        inset-inline-start: 0;
        inline-size: clamp(3rem, 10vi, 8rem);
        block-size: 1px;
        background: color-mix(in srgb, var(--color-accent) 48%, var(--color-border));
    }

    [data-case-study-mode="visual"] .project-section h2 {
        max-inline-size: 22ch;
        font-size: clamp(1.6rem, 3.4vi, 2.6rem);
        line-height: 1.12;
    }

    [data-case-study-mode="visual"] .project-section > p:first-of-type {
        max-inline-size: 68ch;
        color: var(--color-text);
        font-size: clamp(1.02rem, 1.5vi, 1.15rem);
        line-height: 1.75;
    }

    [data-case-study-mode="visual"] .project-section > :is(p, ul, ol):not(:first-child) {
        max-inline-size: 72ch;
    }

    [data-case-study-mode="visual"] :is(.project-fact dt, .project-meta dt, .project-section h3) {
        font-family: var(--font-mono);
    }

    [data-case-study-mode="visual"] .visual-placeholder {
        margin-block: clamp(0.75rem, 2vi, 1.5rem) 0;
    }

    [data-case-study-mode="visual"] .visual-placeholder img {
        max-block-size: min(66vh, 38rem);
        border-color: color-mix(in srgb, var(--color-border) 76%, transparent);
    }

    [data-case-study-mode="visual"] .visual-placeholder--wide {
        max-inline-size: 64rem;
        margin-inline: auto;
    }

    [data-case-study-mode="visual"] .visual-placeholder--inset {
        max-inline-size: 50rem;
        margin-inline: auto;
    }

    [data-case-study-mode="visual"] .visual-placeholder--portrait {
        max-inline-size: 30rem;
        margin-inline: auto;
    }

    [data-case-study-mode="visual"] .visual-placeholder--portrait img {
        aspect-ratio: 4 / 5;
    }

    @container case-study (min-width: 36rem) {
        .case-study-toolbar {
            justify-content: flex-end;
        }

        .project-header__meta {
            grid-template-columns: repeat(2, minmax(0, 1fr));
        }

        .project-nav {
            grid-template-columns: repeat(3, minmax(0, 1fr));
            align-items: center;
        }

        .project-nav > :nth-child(2) {
            text-align: center;
        }

        .project-nav > :last-child {
            text-align: end;
        }
    }

    @container case-study (min-width: 58rem) {
        [data-case-study-mode="visual"] .project-header__grid {
            grid-template-columns: minmax(0, 1fr);
        }

        [data-case-study-mode="visual"] .project-header__hero {
            aspect-ratio: var(--case-visual-hero-ratio);
        }

        [data-case-study-mode="visual"] .project-section__split {
            grid-template-columns: repeat(2, minmax(0, 1fr));
        }

        [data-case-study-mode="visual"] .project-section__split--wide {
            grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
        }

        [data-case-study-mode="visual"] .comparison-box {
            grid-template-columns: repeat(2, minmax(0, 1fr));
        }

    }

    @media (max-width: 35.999rem) {
        .case-study-toolbar {
            align-items: stretch;
            flex-direction: column;
        }

        .case-study-switch {
            inline-size: 100%;
        }

        .project-header__title {
            font-size: clamp(2rem, 14vi, 3.25rem);
        }
    }

@media (prefers-reduced-motion: reduce) {
    [data-case-study-mode="visual"] {
        scroll-behavior: auto;
    }

    .case-study-shell {
        scroll-behavior: auto;
    }
}