/* ============================================================================
   Volume table-of-contents pages
   Layers eco design-system styling on top of home-v2.css (tokens, nav, footer).
   ============================================================================ */

.contents-page {
    max-width: 760px;
    margin-inline: auto;
    padding-inline: var(--gutter);
}

@media (min-width: 768px) {
    .contents-page {
        padding-inline: var(--gutter-lg);
    }
}

/* ---- Title header (clears the fixed site header) ---- */
.contents-hero {
    padding-top: 8rem;
}

@media (min-width: 768px) {
    .contents-hero {
        padding-top: 9rem;
    }
}

.contents-hero__title {
    margin-top: 1rem;
    font-family: var(--font-display);
    font-weight: 500;
    font-size: clamp(2.5rem, 5.5vw, 4.25rem);
    line-height: 1.04;
    letter-spacing: -0.015em;
    color: var(--color-eco-ink);
    text-wrap: balance;
}

.contents-hero__subtitle {
    margin-top: 0.75rem;
    font-family: var(--font-display);
    font-style: italic;
    font-size: clamp(1.25rem, 2.4vw, 1.75rem);
    line-height: 1.3;
    color: var(--color-eco-ink-soft);
}

/* ---- Intro: cover + description ---- */
.vol-intro {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
    margin: 2.5rem 0;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--color-eco-rule);
    font-family: var(--font-sans);
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--color-eco-ink);
}

.vol-intro__cover {
    width: 180px;
    flex: none;
    border-radius: 6px;
    box-shadow: 0 18px 40px -22px rgba(0, 0, 0, 0.45);
}

@media (max-width: 640px) {
    .vol-intro {
        flex-direction: column;
        align-items: center;
    }

    .vol-intro__cover {
        width: 200px;
    }
}

/* ============================================================================
   Table of contents
   ============================================================================ */
.toc {
    --toc-num-col: 2.6ch;
    --toc-gap: 1ch;
    font-family: var(--font-sans);
    font-size: 1.05rem;
    line-height: 1.5;
    color: var(--color-eco-ink);
}

.toc .contents {
    margin: 0 0 1.5rem;
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--color-eco-ink-soft);
}

.toc .contents__hint {
    margin-left: 0.5ch;
    letter-spacing: 0.04em;
    text-transform: none;
}

.toc-front,
.toc-chapters {
    margin: 0;
    padding: 0;
    list-style: none;
}

/* Shared hover rectangle for all TOC links */
.toc a {
    display: inline-block;
    width: 100%;
    color: var(--color-eco-ink);
    text-decoration: none;
    border-radius: 6px;
    padding: 0.12em 0.4em;
    background-image: linear-gradient(var(--color-eco-green-muted), var(--color-eco-green-muted));
    background-repeat: no-repeat;
    background-size: 0% 100%;
    background-position: 0 0;
    transition:
        background-size 0.18s ease,
        color 0.18s ease;
}

.toc a:hover {
    background-size: 100% 100%;
    color: var(--color-eco-olive-deep);
}

/* ---- Part headings (clickable) ---- */
.toc a.toc-part {
    display: block;
    margin-top: 1.5em;
    padding-top: 1em;
    border-top: 1px dotted var(--color-eco-rule);
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1.6rem;
    letter-spacing: 0.01em;
    color: var(--color-eco-ink);
    font-variant-caps: all-small-caps;
}

/* ---- Front matter / appendices (unnumbered) ---- */
.toc ul.toc-front li {
    position: relative;
    margin: 0.35em 0;
    padding-left: calc(var(--toc-num-col) + var(--toc-gap));
}

/* ---- Chapters (numbered via CSS counters) ---- */
.toc-chapters {
    --toc-start: 0;
    counter-reset: tocItem var(--toc-start);
    margin-top: 0.15em;
}

.toc-chapters > li {
    counter-increment: tocItem;
    margin: 0.35em 0;
    display: grid;
    grid-template-columns: var(--toc-num-col) 1fr;
    column-gap: var(--toc-gap);
    align-items: baseline;
}

.toc-chapters > li::before {
    content: counter(tocItem) ".";
    font-family: var(--font-mono);
    font-size: 0.9em;
    font-variant-numeric: tabular-nums;
    text-align: right;
    color: var(--color-eco-olive-deep);
}

@media (max-width: 920px) {
    /* Disable the hover sweep on touch to avoid sticky partial states */
    .toc a {
        transition: none;
        background-image: none;
    }
}

/* ============================================================================
   Download / request button row
   ============================================================================ */
.eco-btn-row {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin: 1.5rem 0 2rem;
}