:root {
    --detail-primary: #153f59;
    --detail-dark: #0b2e43;
    --detail-green: #23766f;
    --detail-text: #202d34;
    --detail-muted: #6f7b82;
    --detail-line: #dfe6e9;
    --detail-soft: #f4f7f8;
    --detail-white: #ffffff;
}

.detail-container {
    width: min(1120px, calc(100% - 40px));
    margin-inline: auto;
}

.public-header {
    background: var(--detail-white);
    border-bottom: 1px solid var(--detail-line);
}

.public-header-inner {
    min-height: 74px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 25px;
}

.public-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.public-brand img {
    width: 41px;
    height: 41px;
}

.public-brand > span {
    display: flex;
    flex-direction: column;
    line-height: 1.15;
}

.public-brand strong {
    color: var(--detail-dark);
    font-size: 0.9rem;
}

.public-brand small {
    margin-top: 3px;
    color: var(--detail-muted);
    font-size: 0.63rem;
}

.back-to-collection {
    color: var(--detail-primary);
    font-size: 0.72rem;
    font-weight: 800;
}

.book-detail-hero {
    color: var(--detail-white);
    background:
        radial-gradient(circle at 82% 18%, rgba(255, 255, 255, 0.10), transparent 28%),
        linear-gradient(135deg, #0d3b52 0%, #12566a 55%, #1d6d68 100%);
}

.detail-grid {
    min-height: 540px;
    display: grid;
    grid-template-columns: 280px minmax(0, 1fr);
    align-items: center;
    gap: 75px;
    padding-block: 65px;
}

.public-cover-wrap {
    display: flex;
    justify-content: center;
}

.public-cover {
    width: 250px;
    aspect-ratio: 0.69;
    object-fit: cover;
    border-radius: 4px 11px 11px 4px;
    box-shadow:
        -7px 9px 0 rgba(5, 30, 41, 0.16),
        0 24px 45px rgba(4, 29, 40, 0.28);
}

.public-cover-placeholder {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 28px 24px;
    color: var(--detail-white);
    background: linear-gradient(145deg, #1c5677, #102f47);
}

.public-cover-placeholder span,
.public-cover-placeholder small {
    font-size: 0.62rem;
    font-weight: 800;
    letter-spacing: 0.12em;
}

.public-cover-placeholder strong {
    font-size: 1.25rem;
    line-height: 1.3;
}

.book-category,
.section-caption {
    color: #b9e7e1;
    font-size: 0.68rem;
    font-weight: 850;
    letter-spacing: 0.12em;
}

.public-book-copy h1 {
    max-width: 760px;
    margin: 13px 0 10px;
    font-size: clamp(2.25rem, 5vw, 4rem);
    line-height: 1.08;
    letter-spacing: -0.045em;
}

.book-author {
    margin: 0;
    color: rgba(255, 255, 255, 0.72);
    font-size: 0.92rem;
}

.public-metadata {
    display: grid;
    grid-template-columns: repeat(4, minmax(90px, 1fr));
    max-width: 680px;
    margin-top: 34px;
    padding-block: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.public-metadata > div {
    display: flex;
    flex-direction: column;
    padding-right: 15px;
}

.public-metadata span {
    color: rgba(255, 255, 255, 0.55);
    font-size: 0.6rem;
}

.public-metadata strong {
    margin-top: 4px;
    overflow: hidden;
    font-size: 0.72rem;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.read-button {
    min-height: 45px;
    display: inline-flex;
    align-items: center;
    gap: 15px;
    margin-top: 28px;
    padding: 0 17px;
    color: var(--detail-dark);
    background: var(--detail-white);
    border-radius: 7px;
    font-size: 0.72rem;
    font-weight: 850;
}

.file-unavailable {
    display: inline-flex;
    margin-top: 28px;
    padding: 10px 13px;
    color: rgba(255, 255, 255, 0.68);
    border: 1px solid rgba(255, 255, 255, 0.17);
    border-radius: 7px;
    font-size: 0.68rem;
}

.book-description {
    padding-block: 85px;
    background: var(--detail-white);
}

.description-grid {
    display: grid;
    grid-template-columns: 0.55fr 1.45fr;
    gap: 80px;
}

.book-description .section-caption,
.related-section .section-caption {
    color: var(--detail-green);
}

.description-grid h2,
.related-heading h2 {
    margin: 8px 0 0;
    color: var(--detail-dark);
    font-size: 2rem;
    letter-spacing: -0.035em;
}

.description-copy {
    color: var(--detail-muted);
    font-size: 0.88rem;
    line-height: 1.9;
}

.related-section {
    padding-block: 75px;
    background: var(--detail-soft);
    border-top: 1px solid var(--detail-line);
}

.related-heading {
    margin-bottom: 28px;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 22px;
}

.related-card img,
.related-placeholder {
    width: 100%;
    aspect-ratio: 0.69;
    object-fit: cover;
    border-radius: 3px 8px 8px 3px;
}

.related-placeholder {
    display: grid;
    place-items: center;
    color: var(--detail-white);
    background: var(--detail-primary);
    font-size: 1rem;
    font-weight: 900;
}

.related-card > span {
    display: block;
    margin-top: 13px;
    color: var(--detail-green);
    font-size: 0.6rem;
    font-weight: 800;
}

.related-card > strong {
    display: block;
    margin-top: 5px;
    color: var(--detail-dark);
    font-size: 0.8rem;
    line-height: 1.45;
}

.related-card > small {
    display: block;
    margin-top: 5px;
    color: var(--detail-muted);
    font-size: 0.64rem;
}

.public-footer {
    padding-block: 24px;
    color: #91a6b1;
    background: var(--detail-dark);
    font-size: 0.67rem;
}

@media (max-width: 850px) {
    .detail-grid {
        grid-template-columns: 210px minmax(0, 1fr);
        gap: 45px;
    }

    .public-cover {
        width: 205px;
    }

    .public-metadata {
        grid-template-columns: repeat(2, 1fr);
        gap: 18px;
    }

    .description-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

    .related-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 620px) {
    .detail-container {
        width: min(100% - 28px, 1120px);
    }

    .public-brand small {
        display: none;
    }

    .detail-grid {
        grid-template-columns: 1fr;
        gap: 38px;
        padding-block: 50px;
    }

    .public-cover-wrap {
        justify-content: flex-start;
    }

    .public-cover {
        width: 190px;
    }

    .public-book-copy h1 {
        font-size: 2.25rem;
    }

    .related-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 18px 14px;
    }
}