/* ============================================================================
   DOCUMENT VIEWER COMPONENT
   ============================================================================
   
   Main document viewing interface with header, content area, and footer.
   Coordinates with TOC sidebar for document navigation.
   
   Layout Structure:
   - Fixed header at top (title, author, back link)
   - Main content area with TOC sidebar on right
   - Fixed footer at bottom (navigation controls)
   
   Features:
   - Fixed positioned header and footer
   - Flexible content area
   - RTL text support
   - Responsive margins for TOC sidebar
   - Back navigation link
   
   ============================================================================ */

/* ============================================================================
   MAIN CONTAINER
   ============================================================================ */

.document-viewer {
    max-width: var(--content-max-width);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
}


/* ============================================================================
   VIEWER HEADER (Fixed at Top)
   ============================================================================ */

.viewer-header {
    position: fixed;
    top: var(--nav-height);
    inset-inline-end: 0;
    inset-inline-start: var(--rail-width);
    background: var(--color-white);
    padding: 12px 20px;
    border-radius: 0;
    box-shadow: var(--shadow-sm);
    flex-shrink: 0;
    z-index: var(--z-header);
    transition: inset-inline-start var(--duration-base) var(--ease-out);
}

/* Shrink header when a panel is open so title isn't obscured */
.document-viewer:has(.panel-rail-content.open) .viewer-header {
    inset-inline-start: calc(var(--rail-width) + var(--panel-width));
}


/* ============================================================================
   TITLE AND AUTHOR ROW
   ============================================================================ */

.title-author-row {
    display: flex;
    align-items: baseline;  /* Align text baselines */
    gap: 1rem;
    direction: rtl;  /* RTL layout for Arabic */
}

.document-title {
    font-size: 1.25rem;
    color: var(--color-text-primary);
    margin-bottom: 0;
    font-family: var(--font-primary);
    font-weight: var(--font-weight-semibold);
}

.document-author {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    margin-bottom: 0;
    white-space: nowrap;  /* Prevent author from wrapping */
    font-family: var(--font-primary);
}

/* Death year + genre line under the title/author in the reader header. */
.document-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.1em 0.55em;
    margin-top: 4px;
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
    font-family: var(--font-primary);
}
.doc-meta-item { white-space: nowrap; }
.doc-meta-item:not(:first-child)::before {
    content: "·";
    margin-inline-end: 0.55em;
    color: var(--color-text-muted, #9a8466);
}
.doc-meta-death { font-variant-numeric: tabular-nums; }


/* ============================================================================
   BACK LINK
   ============================================================================ */

.back-link {
    display: inline-block;
    color: var(--color-primary);
    text-decoration: none;
    margin-bottom: 10px;
    font-size: 1rem;
    font-family: var(--font-primary);
    transition: var(--transition-color);
}

.back-link:hover {
    text-decoration: underline;
}


/* ============================================================================
   VIEWER MAIN (Content Area)
   ============================================================================ */

.viewer-main {
    display: flex;
    gap: 20px;
    flex: 1;
    margin-inline-start: var(--rail-width);  /* Space for rail tab strip */
    margin-top: 80px;     /* Space for fixed header */
    transition: margin-inline-start var(--duration-base) var(--ease-out);
}

/* Expand margin when a panel is open */
.document-viewer:has(.panel-rail-content.open) .viewer-main {
    margin-inline-start: calc(var(--rail-width) + var(--panel-width));
}


/* ============================================================================
   VIEWER CONTENT (Document Text Area)
   ============================================================================ */

.viewer-content {
    flex: 1;
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow-sm);
}


/* ============================================================================
   VIEWER FOOTER (Fixed at Bottom)
   ============================================================================ */

.viewer-footer {
    position: fixed;
    bottom: 0;
    inset-inline: 0;
    width: 100%;
    height: var(--footer-height);
    flex-shrink: 0;
    z-index: var(--z-nav);
    background: var(--color-sand-footer);
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.1);
    margin: 0;
}


/* ============================================================================
   RESPONSIVE DESIGN
   ============================================================================ */

@media (max-width: 768px) {
    .viewer-header {
        position: relative;
        top: auto;
        inset-inline-start: 0;
        inset-inline-end: 0;
        padding: 15px;
    }

    .document-viewer:has(.panel-rail-content.open) .viewer-header {
        inset-inline-start: 0;
    }
    
    .title-author-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    
    .document-author {
        white-space: normal;
    }
    
    .viewer-main {
        flex-direction: column;
        margin-inline-start: 0;
        margin-top: 20px;
    }
    
    .viewer-content {
        padding: 20px;
    }
    
    .viewer-footer {
        position: relative;
        bottom: auto;
    }
}

@media (max-width: 480px) {
    .viewer-content {
        padding: 15px;
        border-radius: var(--radius-md);
    }
    
    .document-title {
        font-size: 1.125rem;
    }
    
    .document-author {
        font-size: 0.8125rem;
    }
}
/* ----------------------------------------------------------------------------
   Edition & digital-source credit, under the title in the reader.

   Deliberately quiet: it must be readable when a scholar goes looking for the
   edition they are citing, without competing with the text itself.
   ---------------------------------------------------------------------------- */

.document-edition {
    margin-top: 6px;
    font-size: var(--font-size-xs);
    line-height: 1.6;
    color: var(--color-text-secondary);
}

.document-edition__row {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 6px;
}

/* The digital provenance sits a step quieter than the print edition, so the
   two are never mistaken for one another in a citation. */
.document-edition__row--source {
    color: var(--color-text-muted);
    margin-top: 2px;
}

.edition-label {
    color: var(--color-text-muted);
}

.edition-id {
    display: inline-block;
    margin-inline-start: 6px;
    padding: 0 5px;
    border-radius: var(--radius-sm);
    background: var(--color-surface-elevated);
    color: var(--color-text-secondary);
    font-size: 0.95em;
    letter-spacing: 0.02em;
}

.edition-sep {
    color: var(--color-text-muted);
    user-select: none;
}