/* ==========================================================================
   Case study page
   Only touches case-study sections. Nav and footer keep their global styles.
   Override the tokens below (or define --ink / --paper / --accent / --font-*
   in global.css) to match the brand.
   ========================================================================== */

.case-study {
    --cs-ink: var(--ink, #15171a);
    --cs-muted: #5d636b;
    --cs-paper: var(--paper, #ffffff);
    --cs-tint: #f4f2ee;
    --cs-line: rgba(21, 23, 26, 0.14);
    --cs-accent: var(--accent, #a4c66d);
    --cs-dark: #15171a;
    --cs-on-dark: #f4f2ee;

    --cs-font-body: var(--font-body, inherit);
    --cs-font-display: var(--font-display, inherit);

    --cs-gutter: clamp(20px, 5vw, 64px);
    --cs-max: 1240px;
    --cs-section: clamp(72px, 11vw, 160px);
    --cs-radius: 4px;
}

/* ---------- Base helpers ---------- */

.skip-link {
    position: absolute;
    left: 16px;
    top: -60px;
    z-index: 200;
    padding: 10px 16px;
    background: var(--cs-ink);
    color: #fff;
    text-decoration: none;
    border-radius: var(--cs-radius);
}
.skip-link:focus { top: 12px; }

.read-progress {
    position: fixed;
    inset: 0 0 auto 0;
    height: 3px;
    z-index: 150;
    pointer-events: none;
}
.read-progress span {
    display: block;
    height: 100%;
    width: 100%;
    background: var(--cs-accent);
    transform-origin: left center;
    transform: scaleX(0);
}

.case-study main {
    color: var(--cs-ink);
    background: var(--cs-paper);
    font-family: var(--cs-font-body);
    overflow-x: clip;
}

.case-study main :focus-visible,
.case-study .cs-cta:focus-visible {
    outline: 2px solid var(--cs-accent);
    outline-offset: 4px;
}

.eyebrow,
.section-label {
    margin: 0;
    font-size: 0.8125rem;
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--cs-muted);
}
.eyebrow::before,
.section-label::before {
    content: "";
    display: inline-block;
    width: 28px;
    height: 1px;
    margin-right: 12px;
    vertical-align: middle;
    background: var(--cs-accent);
}

/* ---------- 1. Hero ---------- */

.title-sect {
    text-align: left;
    padding: clamp(56px, 9vw, 128px) var(--cs-gutter) 0;
}

.title-wrapper {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 24px;
    max-width: var(--cs-max);
    margin: 0 auto;
}

.title-wrapper .eyebrow { grid-column: 1 / -1; }

.title-wrapper h1 {
    grid-column: 1 / span 9;
    margin: 0;
    font-family: var(--cs-font-display);
    font-size: clamp(2.5rem, 7.2vw, 6rem);
    line-height: 1.02;
    font-weight: 600;
    letter-spacing: -0.03em;
    text-wrap: balance;
}

.title-intro {
    grid-column: 1 / span 6;
    margin: 12px 0 0;
    font-size: clamp(1.125rem, 1.6vw, 1.375rem);
    line-height: 1.55;
    color: var(--cs-muted);
    max-width: 38em;
}

/* ---------- 2. Cover + overview ---------- */

.cover-sect {
    margin: 0;
    padding: clamp(40px, 6vw, 80px) var(--cs-gutter) 0;
    text-align: left;
}

.cover-wrapper {
    display: flex;
    flex-direction: column;
    gap: clamp(36px, 5vw, 64px);
    max-width: var(--cs-max);
    margin: 0 auto;
}

.cover-photo {
    margin: 0;
    /* Break out of the text column for a more cinematic opening image */
    margin-inline: calc(var(--cs-gutter) * -0.5);
}
.cover-photo img {
    display: block;
    width: 100%;
    aspect-ratio: 21 / 10;
    object-fit: cover;
    border-radius: var(--cs-radius);
    background: var(--cs-tint);
}

.headline {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 16px;
    align-items: start;
}
.headline .section-label {
    grid-column: 1 / span 3;
    padding-top: 0.9em;
}
.headline p {
    grid-column: 4 / -1;
    margin: 0;
    font-family: var(--cs-font-display);
    font-size: clamp(1.5rem, 3.4vw, 2.75rem);
    line-height: 1.22;
    font-weight: 500;
    letter-spacing: -0.02em;
    text-wrap: pretty;
}

/* ---------- 3. Process ---------- */

.steps-sect {
    padding: var(--cs-section) var(--cs-gutter) 0;
}

.steps-head {
    max-width: var(--cs-max);
    margin: 0 auto clamp(32px, 5vw, 64px);
    padding-bottom: 20px;
    border-bottom: 1px solid var(--cs-line);
}

.steps-list {
    list-style: none;
    margin: 0 auto;
    padding: 0;
    max-width: var(--cs-max);
    counter-reset: step;
    display: flex;
    flex-direction: column;
    gap: clamp(64px, 10vw, 140px);
}

.step-wrapper {
    counter-increment: step;
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 28px;
    align-items: start;
    margin: 0;
}

.step-cover-img-wrapper {
    grid-column: 1 / span 7;
    grid-row: 1;
    margin: 0;
    width: auto;
}
.step-cover-img-wrapper img {
    display: block;
    width: 100%;
    aspect-ratio: 4 / 3;
    object-fit: cover;
    border-radius: var(--cs-radius);
    background: var(--cs-tint);
}

.step-text {
    grid-column: 9 / -1;
    grid-row: 1;
    position: sticky;
    top: 110px;
    align-self: start;
}

.step-text::before {
    content: counter(step, decimal-leading-zero);
    display: block;
    margin-bottom: 20px;
    font-family: var(--cs-font-display);
    font-size: clamp(3rem, 6vw, 5rem);
    line-height: 1;
    font-weight: 300;
    letter-spacing: -0.04em;
    color: var(--cs-accent);
}

.step-headline {
    margin: 0 0 16px;
    font-family: var(--cs-font-display);
    font-size: clamp(1.5rem, 2.6vw, 2.125rem);
    line-height: 1.15;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.step-text p {
    margin: 0;
    max-width: 34em;
    font-size: 1.0625rem;
    line-height: 1.7;
    color: var(--cs-muted);
}

/* Even steps mirror the layout for rhythm */
.step-wrapper:nth-child(even) .step-cover-img-wrapper { grid-column: 6 / -1; }
.step-wrapper:nth-child(even) .step-text { grid-column: 1 / span 4; }

/* ---------- 4. Conclusion ---------- */

.conclusion-sect {
    margin-top: var(--cs-section);
    padding: var(--cs-section) var(--cs-gutter);
    background: var(--cs-dark);
    color: var(--cs-on-dark);
}

.conclusion-wrapper {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: 24px;
    row-gap: 32px;
    max-width: var(--cs-max);
    margin: 0 auto;
}

.conclusion-wrapper h2 {
    grid-column: 1 / span 5;
    margin: 0;
    font-family: var(--cs-font-display);
    font-size: clamp(2.25rem, 5vw, 4rem);
    line-height: 1.05;
    font-weight: 600;
    letter-spacing: -0.03em;
}

.conclusion-body { grid-column: 7 / -1; }
.conclusion-body p {
    margin: 0 0 36px;
    max-width: 32em;
    font-size: clamp(1.125rem, 1.7vw, 1.375rem);
    line-height: 1.6;
    color: rgba(244, 242, 238, 0.82);
}

.cs-cta {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 14px 4px 10px 0;
    color: var(--cs-on-dark);
    font-weight: 600;
    text-decoration: none;
    border-bottom: 1px solid currentColor;
    transition: gap 0.25s ease, color 0.25s ease;
}
.cs-cta:hover { gap: 20px; color: #fff; }

/* ---------- Motion (progressive enhancement) ---------- */

.js .reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}
.js .reveal.is-visible {
    opacity: 1;
    transform: none;
}

@media (prefers-reduced-motion: reduce) {
    .js .reveal { opacity: 1; transform: none; transition: none; }
    .cs-cta { transition: none; }
}

/* ---------- Tablet ---------- */

@media (max-width: 991px) {
    .title-wrapper h1 { grid-column: 1 / -1; }
    .title-intro { grid-column: 1 / span 9; }

    .headline .section-label { grid-column: 1 / -1; padding-top: 0; }
    .headline p { grid-column: 1 / -1; }

    .step-wrapper { row-gap: 24px; }
    .step-cover-img-wrapper,
    .step-wrapper:nth-child(even) .step-cover-img-wrapper {
        grid-column: 1 / -1;
        grid-row: 1;
    }
    .step-text,
    .step-wrapper:nth-child(even) .step-text {
        grid-column: 1 / span 9;
        grid-row: 2;
        position: static;
    }

    .conclusion-wrapper h2 { grid-column: 1 / -1; }
    .conclusion-body { grid-column: 1 / -1; }
}

/* ---------- Mobile ---------- */

@media (max-width: 600px) {
    .title-intro { grid-column: 1 / -1; }

    .cover-photo { margin-inline: calc(var(--cs-gutter) * -1); }
    .cover-photo img { aspect-ratio: 4 / 3; border-radius: 0; }

    .step-text,
    .step-wrapper:nth-child(even) .step-text { grid-column: 1 / -1; }
}