/*
 * Subject pages
 *
 * Applies to:
 * /subjects
 * /subject/{slug}
 */


/* ---------------------------------------------------------
   Subject directory
   --------------------------------------------------------- */

.subject-directory {
    margin-top: 2rem;
}

.subject-list,
.subject-children,
.subject-child-list {
    margin: 0;
    padding-left: 1.5rem;
}

.subject-list {
    padding-left: 0;
    list-style: none;
}

.subject-item {
    margin-bottom: 0.75rem;
}

.subject-item > a {
    font-weight: 600;
}

.subject-children {
    margin-top: 0.5rem;
}

.subject-child-list {
    columns: 2;
    column-gap: 2rem;
}

.subject-child-list li {
    margin-bottom: 0.5rem;
    break-inside: avoid;
}


/* ---------------------------------------------------------
   Subject detail
   --------------------------------------------------------- */

.subject-description {
    margin: 1.5rem 0 2rem;
    line-height: 1.7;
}

.subject-parent-context,
.subject-children-section {
    margin-top: 2rem;
}

.subject-parent-context p {
    margin: 0;
    line-height: 1.7;
}


/* ---------------------------------------------------------
   Discovery tabs
   --------------------------------------------------------- */

.subject-discovery {
    margin-top: 2.5rem;
}

.subject-tabs {
    display: flex;
    gap: 0;
    margin-bottom: 0;
    border-bottom: 1px solid #d8d8d8;
}

.subject-tabs a {
    display: inline-block;
    padding: 0.9rem 1.25rem;
    border: 1px solid transparent;
    border-bottom: 0;
    text-decoration: none;
    font-weight: 600;
}

.subject-tabs a:hover {
    text-decoration: underline;
}

.subject-tabs a[aria-current="page"] {
    position: relative;
    margin-bottom: -1px;
    border-color: #d8d8d8;
    border-bottom-color: #ffffff;
    background: #ffffff;
    text-decoration: none;
}


/* ---------------------------------------------------------
   Search panels
   --------------------------------------------------------- */

.subject-journal-panel,
.subject-article-panel {
    padding: 1.5rem 0 0;
}

.subject-search-form {
    display: grid;
    grid-template-columns: minmax(180px, 240px) minmax(260px, 1fr) auto;
    gap: 1rem;
    align-items: end;
    margin: 1rem 0 2rem;
    padding: 1.25rem;
    border: 1px solid #dddddd;
    border-radius: 4px;
}

.subject-search-form > div {
    min-width: 0;
}

.subject-search-form label {
    display: block;
    margin-bottom: 0.4rem;
    font-weight: 600;
}

.subject-search-form select,
.subject-search-form input[type="search"] {
    width: 100%;
    min-height: 2.5rem;
    box-sizing: border-box;
}

.subject-search-form button {
    min-height: 2.5rem;
}

.subject-search-form a {
    display: inline-block;
    margin-left: 0.75rem;
}


/* ---------------------------------------------------------
   Journal results
   --------------------------------------------------------- */

.journal-list {
    display: grid;
    gap: 1rem;
    margin-top: 1rem;
}

.journal-item {
    padding: 1.25rem;
    border: 1px solid #dddddd;
    border-radius: 4px;
}

.journal-item h3 {
    margin-top: 0;
    margin-bottom: 0.75rem;
}

.journal-item p {
    margin: 0.35rem 0;
}

.subject-journal-panel .journal-list {
    display: grid;
    gap: 1rem;
    margin-top: 1rem;
}

.subject-journal-panel .journal-item {
    padding: 1.25rem;
    border: 1px solid #dddddd;
    border-radius: 4px;
}

.subject-journal-panel .journal-item.has-journal-cover {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 1.25rem;
    align-items: start;
}

.subject-journal-panel .journal-card-cover {
    display: block;
    width: fit-content;
    text-decoration: none;
}

.subject-journal-panel .journal-item.has-journal-cover
.journal-card-cover img {
    display: block;
    width: auto;
    height: 150px;
    max-width: 140px;
    object-fit: contain;
    border: 1px solid #dddddd;
    border-radius: 3px;
}

.subject-journal-panel .journal-card-content {
    min-width: 0;
}

.subject-journal-panel .journal-item h3 {
    margin-top: 0;
    margin-bottom: 0.75rem;
}

.subject-journal-panel .journal-card-issn,
.subject-journal-panel .journal-card-publisher {
    margin: 0.35rem 0;
    line-height: 1.6;
}

.subject-journal-panel .journal-card-description {
    margin: 0.75rem 0 0;
    line-height: 1.65;
}


/* ---------------------------------------------------------
   Article results
   --------------------------------------------------------- */

.subject-article-panel .article-list {
    display: grid;
    gap: 1rem;
    margin-top: 1rem;
}

.subject-article-panel .article-item {
    padding: 1.25rem;
    border: 1px solid #dddddd;
    border-radius: 4px;
}

.subject-article-panel .article-item.has-graphical-abstract {
    display: grid;
    grid-template-columns: 180px minmax(0, 1fr);
    gap: 1.25rem;
    align-items: start;
}

.subject-article-panel .article-card-graphical-abstract {
    display: block;
    width: 100%;
    text-decoration: none;
}

.subject-article-panel .article-card-graphical-abstract img {
    display: block;
    width: 100%;
    height: auto;
    max-height: 180px;
    object-fit: contain;
    border: 1px solid #dddddd;
    border-radius: 3px;
}

.subject-article-panel .article-card-content {
    min-width: 0;
}

.subject-article-panel .article-item h3 {
    margin-top: 0;
    margin-bottom: 0.75rem;
}

.subject-article-panel .article-card-authors {
    margin: 0.25rem 0 0.5rem;
    line-height: 1.6;
}

.subject-article-panel .article-publication-details {
    margin: 0.35rem 0;
    line-height: 1.6;
}

.subject-article-panel .article-card-meta {
    margin: 0.35rem 0 0;
    line-height: 1.6;
}

/* ---------------------------------------------------------
   Responsive
   --------------------------------------------------------- */

@media (max-width: 800px) {
    .subject-search-form {
        grid-template-columns: 1fr;
        align-items: stretch;
    }

    .subject-search-form a {
        margin-left: 0.5rem;
    }

    .subject-child-list {
        columns: 1;
    }

    .subject-tabs {
        flex-direction: column;
        border-bottom: 0;
    }

    .subject-tabs a {
        border: 1px solid #d8d8d8;
        border-bottom: 0;
    }

    .subject-tabs a:last-child {
        border-bottom: 1px solid #d8d8d8;
    }

    .subject-tabs a[aria-current="page"] {
        margin-bottom: 0;
        border-bottom-color: #d8d8d8;
        font-weight: 700;
    }
}

/* ---------------------------------------------------------
   Expandable subject taxonomy
   /subjects
   --------------------------------------------------------- */

.subject-tree-root,
.subject-tree-children {
    margin: 0;
    padding: 0;
    list-style: none;
}

.subject-tree-root {
    margin-top: 1.5rem;
}

.subject-tree-item {
    margin: 0;
}

.subject-tree-row {
    display: flex;
    align-items: center;
    gap: 0.45rem;
    min-height: 2.5rem;
    padding: 0.25rem 0;
}

.subject-tree-link {
    display: inline-block;
    line-height: 1.5;
    text-decoration: none;
}

.subject-tree-link:hover {
    text-decoration: underline;
}

/*
 * Level-1 rows are visually stronger.
 */
.subject-tree-root > .subject-tree-item > .subject-tree-row
    > .subject-tree-link {
    font-weight: 600;
}

/*
 * Nested hierarchy indentation.
 */
.subject-tree-children {
    margin-left: 1rem;
    padding-left: 1.25rem;
    border-left: 1px solid #dddddd;
}

/*
 * Disclosure button.
 */
.subject-toggle {
    display: inline-flex;
    flex: 0 0 1.75rem;
    width: 1.75rem;
    height: 1.75rem;
    align-items: center;
    justify-content: center;
    padding: 0;
    border: 0;
    background: transparent;
    font: inherit;
    font-size: 1.15rem;
    font-weight: 600;
    line-height: 1;
    cursor: pointer;
}

.subject-toggle:hover {
    background: rgba(0, 0, 0, 0.05);
    border-radius: 3px;
}

.subject-toggle:focus-visible {
    outline: 2px solid currentColor;
    outline-offset: 2px;
    border-radius: 3px;
}

.subject-toggle-icon {
    display: inline-block;
    font-size: 1.25rem;
    font-weight: 600;
    line-height: 1;
}

/*
 * Keeps leaf subjects aligned with expandable subjects.
 */
.subject-toggle-placeholder {
    display: inline-block;
    flex: 0 0 1.75rem;
    width: 1.75rem;
}

/*
 * Respect the HTML hidden attribute.
 */
.subject-tree-children[hidden] {
    display: none;
}


/* ---------------------------------------------------------
   Screen-reader utility
   --------------------------------------------------------- */

.visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}


/* ---------------------------------------------------------
   Expandable taxonomy responsive behavior
   --------------------------------------------------------- */

@media (max-width: 600px) {
    .subject-tree-children {
        margin-left: 0.6rem;
        padding-left: 0.8rem;
    }

    .subject-tree-row {
        align-items: flex-start;
    }
    
    .subject-article-panel .article-item.has-graphical-abstract {
        grid-template-columns: 1fr;
    }
    
    .subject-journal-panel .journal-item.has-journal-cover {
        grid-template-columns: 1fr;
    }
    
}