:root {
    /* Zensical / Material indigo */
    --pico-primary: #4051b5;
    --pico-primary-hover: #526cfe;
    --pico-primary-background: #4051b5;
    --pico-primary-inverse: #fff;
    --pico-font-family-sans-serif: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    --pico-font-family: var(--pico-font-family-sans-serif);
    --pico-font-family-monospace: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
    --pico-font-weight: 400;
    --pico-line-height: 1.6;
    --pico-border-radius: 0.375rem;

    /* Pastel tag tints (background + foreground pairs) */
    --tag-condition-bg: #fce4ec;
    --tag-condition-fg: #8a1f4a;
    --tag-mechanism-bg: #e3eaff;
    --tag-mechanism-fg: #1f3a93;
    --tag-treatment-bg: #e3f1e7;
    --tag-treatment-fg: #1b5e3a;
    --tag-category-bg: #ececec;
    --tag-category-fg: #495057;
}

@media (prefers-color-scheme: dark) {
    :root {
        --pico-primary: #5d6cc0;
        --pico-primary-hover: #7a8bff;
        --pico-primary-background: #5d6cc0;
        --pico-primary-inverse: #fff;

        --tag-condition-bg: #3a1f2a;
        --tag-condition-fg: #f2a3c0;
        --tag-mechanism-bg: #1f2742;
        --tag-mechanism-fg: #a8b6ff;
        --tag-treatment-bg: #1f2e26;
        --tag-treatment-fg: #9bd4ad;
        --tag-category-bg: #2a2a2a;
        --tag-category-fg: #b8b8b8;
    }
}

body {
    font-family: var(--pico-font-family-sans-serif);
}

h1, h2, h3, h4 {
    font-weight: 500;
    letter-spacing: -0.01em;
}

/* Centered, constrained content like Zensical's md-grid */
main {
    max-width: 61rem;
    margin-inline: auto;
    padding-inline: 1.5rem;
}

header {
    margin-bottom: 1.5rem;
}
header .subtitle { color: var(--pico-muted-color); margin: 0; }
header .header-row {
    display: flex;
    align-items: baseline;
    gap: 1rem;
}
header .header-row h1 { margin: 0; }

.lang-switcher {
    margin-left: auto;
    width: auto;
    flex: 0 0 auto;
    display: inline-flex;
    align-items: baseline;
    gap: 0.4rem;
    font-size: 0.7rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    line-height: 1;
}
.lang-switcher .lang-btn {
    display: inline-block;
    padding: 0;
    line-height: 1;
    text-decoration: none;
    color: var(--pico-muted-color);
    background: transparent;
    /* underline drawn as a drop shadow below the box — no layout impact */
    box-shadow: 0 2px 0 transparent;
    transition: color 0.15s ease, box-shadow 0.15s ease;
}
.lang-switcher .lang-btn:hover { color: var(--pico-color); }
.lang-switcher .lang-btn.active {
    color: var(--pico-color);
    box-shadow: 0 2px 0 var(--pico-primary);
    cursor: default;
}

.lang-fallback {
    margin: 0.35rem 0 0 0;
    color: var(--pico-muted-color);
}

#filters {
    background: var(--pico-card-background-color);
    border: 1px solid var(--pico-card-border-color);
    border-radius: var(--pico-border-radius);
    padding: 1.25rem;
    margin-bottom: 1.5rem;
}
.search-input {
    width: 100%;
    margin: 0 0 1rem 0;
    padding: 0.55rem 1rem;
    font-size: 0.9rem;
    line-height: 1.3;
    height: auto;
    background: var(--pico-background-color);
    color: var(--pico-color);
}
.search-input:focus {
    outline: none;
    border-color: var(--pico-primary);
}

.tag-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
}
.tag-chip {
    cursor: pointer;
    user-select: none;
    padding: 0.35rem 0.85rem;
    border: 1px solid transparent;
    border-radius: 999px;
    font-size: 0.75rem;
    line-height: 1.3;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    margin: 0;
    opacity: 0.55;
    transition: opacity 0.15s ease, box-shadow 0.15s ease;
}
.tag-chip:hover { opacity: 0.85; }
.tag-chip:has(input:checked) {
    opacity: 1;
    box-shadow: inset 0 0 0 1.5px currentColor;
}
.tag-chip input { display: none; }

.tag-chip-condition { background: var(--tag-condition-bg); color: var(--tag-condition-fg); }
.tag-chip-mechanism { background: var(--tag-mechanism-bg); color: var(--tag-mechanism-fg); }
.tag-chip-treatment { background: var(--tag-treatment-bg); color: var(--tag-treatment-fg); }
.tag-chip-category  { background: var(--tag-category-bg);  color: var(--tag-category-fg);  }

.result-count {
    font-size: 0.9rem;
    color: var(--pico-muted-color);
    margin-bottom: 0.5rem;
}

.article-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.article-card {
    border: 1px solid var(--pico-card-border-color);
    border-radius: var(--pico-border-radius);
    padding: 1.25rem;
    background: var(--pico-card-background-color);
}
.article-meta {
    font-size: 0.85rem;
    color: var(--pico-muted-color);
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}
.article-content h3 {
    margin: 0 0 0.25rem 0;
    font-size: 1.1rem;
    line-height: 1.3;
}
.article-content .authors {
    font-size: 0.85rem;
    color: var(--pico-muted-color);
    margin: 0 0 0.5rem 0;
}
.article-content .summary {
    margin: 0;
    font-size: 0.95rem;
}
.pending { color: var(--pico-muted-color); }

/* Structured abstract sections */
.summary-sections {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
    margin: 0;
}
.summary-section {
    margin: 0;
    font-size: 0.95rem;
    line-height: 1.55;
}
.section-label {
    font-weight: 600;
    margin-right: 0.4rem;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--section-color, var(--pico-muted-color));
}
.section-label::before {
    margin-right: 0.3rem;
    font-size: 0.95rem;
    line-height: 1;
}
.section-label[data-section="background"]   { --section-color: #1f3a93; }
.section-label[data-section="background"]::before   { content: "🎯"; }
.section-label[data-section="methods"]      { --section-color: #1b5e3a; }
.section-label[data-section="methods"]::before      { content: "🔬"; }
.section-label[data-section="results"]      { --section-color: #8a1f4a; }
.section-label[data-section="results"]::before      { content: "📊"; }
.section-label[data-section="conclusions"]  { --section-color: #7a5b00; }
.section-label[data-section="conclusions"]::before  { content: "💡"; }

@media (prefers-color-scheme: dark) {
    .section-label[data-section="background"]   { --section-color: #a8b6ff; }
    .section-label[data-section="methods"]      { --section-color: #9bd4ad; }
    .section-label[data-section="results"]      { --section-color: #f2a3c0; }
    .section-label[data-section="conclusions"]  { --section-color: #ffd97a; }
}

.article-tags {
    list-style: none;
    padding: 0;
    margin: 0.75rem 0 0 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0.3rem;
}
.article-tags li {
    list-style: none;
    padding: 0;
}
.article-tags li::marker,
.article-tags li::before { content: none; }
.article-tags .tag {
    font-size: 0.75rem;
    padding: 0.35rem 0.85rem;
    border-radius: 999px;
    font-weight: 500;
    display: inline-block;
    line-height: 1.3;
}
.tag-condition  { background: var(--tag-condition-bg); color: var(--tag-condition-fg); }
.tag-mechanism  { background: var(--tag-mechanism-bg); color: var(--tag-mechanism-fg); }
.tag-treatment  { background: var(--tag-treatment-bg); color: var(--tag-treatment-fg); }
.tag-category   { background: var(--tag-category-bg);  color: var(--tag-category-fg); }

.pagination {
    margin: 1.5rem 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
    align-items: center;
    justify-content: center;
}
.pagination .page-link {
    min-width: 2.25rem;
    padding: 0.25rem 0.6rem;
    border: 1px solid var(--pico-card-border-color);
    border-radius: var(--pico-border-radius);
    text-align: center;
    text-decoration: none;
    line-height: 1.4;
    font-size: 0.9rem;
    cursor: pointer;
    user-select: none;
}
.pagination .page-link:hover:not(.disabled):not(.current):not(.ellipsis) {
    background: var(--pico-primary-background);
    color: var(--pico-primary-inverse);
    border-color: var(--pico-primary);
}
.pagination .page-link.current {
    background: var(--pico-primary);
    color: var(--pico-primary-inverse);
    border-color: var(--pico-primary);
    cursor: default;
}
.pagination .page-link.disabled {
    color: var(--pico-muted-color);
    cursor: not-allowed;
    opacity: 0.5;
}
.pagination .page-link.ellipsis {
    border: none;
    cursor: default;
    padding: 0.25rem 0.25rem;
}