/* English comments are mandatory. */
/* Layout — sidebar, header, main content area, auth pages, responsive. */

/* ================================================================
   APP SHELL (authenticated layout)
   ================================================================ */
.app-layout {
    display: flex;
    min-height: 100vh;
}

.app-main {
    flex: 1;
    margin-left: var(--sidebar-width);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: margin-left var(--transition-slow);
}

.app-layout.sidebar-collapsed .app-main {
    margin-left: var(--sidebar-collapsed);
}

/* ================================================================
   SIDEBAR
   ================================================================ */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: var(--sidebar-width);
    background: var(--bg-sidebar);
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: width var(--transition-slow);
    overflow-x: hidden;
    overflow-y: auto;
}

.sidebar-collapsed .sidebar {
    width: var(--sidebar-collapsed);
}

/* Logo area */
.sidebar-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-5) var(--space-5);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    min-height: var(--header-height);
    text-decoration: none;
}

.sidebar-logo-icon {
    font-size: var(--font-size-xl);
    flex-shrink: 0;
    width: 28px;
    text-align: center;
}

.sidebar-logo-icon svg {
    width: 24px;
    height: 24px;
    vertical-align: middle;
    display: inline-block;
}

.sidebar-logo-text {
    font-family: var(--font-display);
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--text-sidebar-active);
    white-space: nowrap;
    overflow: hidden;
    transition: opacity var(--transition);
}

.sidebar-logo-badge {
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--accent);
    background: var(--accent-subtle);
    padding: 1px 6px;
    border-radius: var(--radius-full);
    white-space: nowrap;
    transition: opacity var(--transition);
}

.sidebar-collapsed .sidebar-logo-text,
.sidebar-collapsed .sidebar-logo-badge {
    opacity: 0;
    width: 0;
}

/* Navigation */
.sidebar-nav {
    flex: 1;
    padding: var(--space-3) var(--space-3);
    overflow-y: auto;
}

.sidebar-section-label {
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: var(--space-4) var(--space-3) var(--space-2);
    white-space: nowrap;
    overflow: hidden;
    transition: opacity var(--transition);
}

.sidebar-collapsed .sidebar-section-label {
    opacity: 0;
    height: 0;
    padding: 0;
    margin: 0;
}

.sidebar-divider {
    height: 1px;
    background: rgba(255, 255, 255, 0.06);
    margin: var(--space-2) var(--space-3);
}

.sidebar-link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-3);
    border-radius: var(--radius-md);
    color: var(--text-sidebar);
    text-decoration: none;
    font-size: var(--font-size-base);
    font-weight: 500;
    white-space: nowrap;
    transition: background var(--transition), color var(--transition);
    position: relative;
}

.sidebar-link:hover {
    background: var(--bg-sidebar-hover);
    color: var(--text-sidebar-active);
}

.sidebar-link.active {
    background: var(--bg-sidebar-active);
    color: var(--text-sidebar-active);
}

.sidebar-link:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: -2px;
}

.sidebar-link.active::before {
    content: '';
    position: absolute;
    left: -12px;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background: var(--accent);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.sidebar-link-icon {
    font-size: var(--font-size-md);
    flex-shrink: 0;
    width: 24px;
    text-align: center;
}

.sidebar-link-text {
    overflow: hidden;
    transition: opacity var(--transition);
}

.sidebar-collapsed .sidebar-link-text {
    opacity: 0;
    width: 0;
}

/* Sidebar collapse toggle button */
.sidebar-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-4);
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--text-sidebar);
    cursor: pointer;
    transition: color var(--transition);
}

.sidebar-toggle:hover {
    color: var(--text-sidebar-active);
}

/* Tooltip for collapsed sidebar — positioned relative to viewport to avoid clipping */
.sidebar-collapsed .sidebar-link[data-tooltip]::after {
    content: attr(data-tooltip);
    position: fixed;
    left: calc(var(--sidebar-collapsed) + 8px);
    top: auto;
    background: var(--bg-card);
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
    white-space: nowrap;
    z-index: 200;
    pointer-events: none;
    opacity: 0;
    transition: opacity var(--transition);
}

.sidebar-collapsed .sidebar-link[data-tooltip]:hover::after {
    opacity: 1;
}

/* ================================================================
   HEADER
   ================================================================ */
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
    padding: 0 var(--space-6);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 50;
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-width: 0;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    flex-shrink: 0;
}

/* Breadcrumbs */
.breadcrumbs {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    overflow: hidden;
}

.breadcrumbs a {
    color: var(--text-muted);
    white-space: nowrap;
}

.breadcrumbs a:hover {
    color: var(--accent);
}

.breadcrumbs-separator {
    color: var(--text-muted);
    flex-shrink: 0;
}

.breadcrumbs-current {
    color: var(--text-primary);
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Header user section */
.header-user {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.header-user-email {
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Theme toggle */
.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--font-size-md);
    transition: background var(--transition);
}

.theme-toggle:hover {
    background: var(--bg-hover);
}

/* Hamburger (mobile) — use CSS bars for reliable rendering */
.hamburger {
    display: none;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    cursor: pointer;
    color: var(--text-secondary);
    flex-direction: column;
    gap: 4px;
    padding: 10px;
}

.hamburger-bar {
    display: block;
    width: 20px;
    height: 2px;
    background: currentColor;
    border-radius: 1px;
}

.hamburger:hover {
    background: var(--bg-hover);
}

/* ================================================================
   PAGE CONTENT
   ================================================================ */
#page-content {
    flex: 1;
    padding: var(--space-6);
    max-width: var(--content-max-width);
    width: 100%;
    margin: 0 auto;
}

/* Page header (title + actions row) */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-6);
    gap: var(--space-4);
}

.page-header h1 {
    font-size: var(--font-size-2xl);
}

.page-header-actions {
    display: flex;
    gap: var(--space-3);
    flex-shrink: 0;
}

/* ================================================================
   AUTH PAGES (login / register — no sidebar)
   ================================================================ */
.auth-layout {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: var(--space-6);
    background: var(--bg-primary);
}

/* Center auth card inside page-content */
.auth-layout #page-content {
    display: flex;
    align-items: center;
    justify-content: center;
    max-width: none;
    padding: 0;
    margin: 0;
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: var(--space-10) var(--space-8);
}

.auth-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    margin-bottom: var(--space-8);
}

.auth-logo-icon {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
}

.auth-logo-icon svg {
    width: 32px;
    height: 32px;
    display: block;
}

.auth-logo-title {
    font-family: var(--font-display);
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
}

.auth-logo-badge {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--accent);
    background: var(--accent-subtle);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    margin-left: var(--space-2);
    vertical-align: super;
}

.auth-title {
    font-size: var(--font-size-xl);
    text-align: center;
    margin-bottom: var(--space-6);
}

.auth-footer {
    text-align: center;
    margin-top: var(--space-6);
    font-size: var(--font-size-sm);
    color: var(--text-muted);
}

.auth-footer a {
    font-weight: 500;
}

/* ================================================================
   SIDEBAR OVERLAY (mobile)
   ================================================================ */
.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 90;
}

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

/* Tablet: sidebar collapsed by default */
@media (max-width: 1024px) {
    .app-main {
        margin-left: var(--sidebar-collapsed);
    }

    .sidebar {
        width: var(--sidebar-collapsed);
    }

    .sidebar-logo-text,
    .sidebar-logo-badge,
    .sidebar-link-text,
    .sidebar-section-label {
        opacity: 0;
        width: 0;
        height: auto;
        padding-top: 0;
        padding-bottom: 0;
    }

    /* Show full sidebar on hover (desktop tablet) */
    .sidebar:hover {
        width: var(--sidebar-width);
    }

    .sidebar:hover .sidebar-logo-text,
    .sidebar:hover .sidebar-logo-badge,
    .sidebar:hover .sidebar-link-text {
        opacity: 1;
        width: auto;
    }

    .sidebar:hover .sidebar-section-label {
        opacity: 1;
        height: auto;
        padding: var(--space-4) var(--space-3) var(--space-2);
    }
}

/* Mobile: sidebar hidden, hamburger visible */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .sidebar {
        width: var(--sidebar-width);
        transform: translateX(-100%);
        transition: transform var(--transition-slow);
    }

    /* Sidebar open state (toggled via JS) — reset all tablet hiding */
    .sidebar-open .sidebar {
        transform: translateX(0);
    }

    .sidebar-open .sidebar .sidebar-logo-text,
    .sidebar-open .sidebar .sidebar-logo-badge,
    .sidebar-open .sidebar .sidebar-link-text {
        opacity: 1;
        width: auto;
    }

    .sidebar-open .sidebar .sidebar-section-label {
        opacity: 1;
        width: auto;
        height: auto;
        padding: var(--space-4) var(--space-3) var(--space-2);
    }

    /* Hide collapse toggle on mobile — overlay mode, no need */
    .sidebar-toggle {
        display: none;
    }

    .sidebar-open .sidebar-overlay {
        display: block;
    }

    /* On mobile, sidebar overlays — no margin shift */
    .sidebar:hover {
        width: var(--sidebar-width);
    }

    .app-main {
        margin-left: 0;
    }

    #page-content {
        padding: var(--space-4);
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .header-user-email {
        display: none;
    }

    /* Stat cards: smaller minimum on mobile */
    .stats-row {
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    }

    /* Touch targets: minimum 44x44px */
    .btn,
    .pagination-btn,
    .theme-toggle {
        min-height: 44px;
        min-width: 44px;
    }
}

/* Wide screens */
@media (min-width: 1440px) {
    #page-content {
        max-width: 1400px;
    }
}