/* ==========================================================================
   Side Navigation — Desktop sidebar + Mobile hamburger overlay
   Phase B of v0.8.0 Sage redesign
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS custom properties — :root scope for cross-element use
   -------------------------------------------------------------------------- */
:root {
    --side-nav-width: 240px;
    --side-nav-collapsed-width: 64px;
    --side-nav-transition: 0.2s ease;
}

.side-nav {
    --side-nav-bg: var(--card-background);
    --side-nav-border: var(--border-color);
}

/* --------------------------------------------------------------------------
   Side nav — base layout
   -------------------------------------------------------------------------- */
.side-nav {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: var(--side-nav-width);
    background: var(--side-nav-bg);
    border-right: 1px solid var(--side-nav-border);
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: width var(--side-nav-transition);
    overflow: hidden;
}

/* --------------------------------------------------------------------------
   Header (logo + toggle)
   -------------------------------------------------------------------------- */
.side-nav-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    min-height: 64px;
    flex-shrink: 0;
}

.side-nav-logo {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    font-family: var(--font-heading);
    font-size: 1.375rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    white-space: nowrap;
    overflow: hidden;
}

.side-nav-logo:hover {
    color: var(--primary-dark);
}

.side-nav-logo-text {
    transition: opacity var(--side-nav-transition);
}

/* Toggle button (chevron / pin) */
.side-nav-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    flex-shrink: 0;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.side-nav-toggle:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.side-nav-toggle:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Pin icon hidden by default, chevron visible */
.side-nav-toggle .toggle-pin {
    display: none;
}

.side-nav-toggle .toggle-chevron {
    display: block;
    transition: transform var(--side-nav-transition);
}

/* --------------------------------------------------------------------------
   Scrollable nav area (between header and footer)
   -------------------------------------------------------------------------- */
.side-nav-scroll {
    flex: 1 1 0;
    overflow-y: auto;
    overflow-x: hidden;
    min-height: 0;
}

/* Hide scrollbar but keep functional (WebKit + Firefox) */
.side-nav-scroll::-webkit-scrollbar {
    width: 0;
}

.side-nav-scroll {
    scrollbar-width: none;
}

/* --------------------------------------------------------------------------
   Nav groups
   -------------------------------------------------------------------------- */
.side-nav-group {
    display: flex;
    flex-direction: column;
    gap: 2px;
    padding: 0.5rem 0.5rem;
}

.side-nav-group+.side-nav-group {
    border-top: 1px solid var(--border-light);
    margin-top: 0.25rem;
    padding-top: 0.75rem;
}

.side-nav-group-label {
    font-family: var(--font-heading);
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--ink-mid);
    padding: 0.25rem 0.75rem 0.375rem;
    white-space: nowrap;
    overflow: hidden;
    transition: opacity var(--side-nav-transition);
}

/* --------------------------------------------------------------------------
   Nav links
   -------------------------------------------------------------------------- */
.side-nav-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--border-radius-sm);
    min-height: 44px;
    text-decoration: none;
    white-space: nowrap;
    overflow: hidden;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    position: relative;
}

.side-nav-link:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.side-nav-link:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: -2px;
}

.side-nav-link.active {
    background: var(--primary-light);
    color: var(--primary-dark);
    font-weight: 600;
}

/* Active indicator bar */
.side-nav-link.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 6px;
    bottom: 6px;
    width: 3px;
    border-radius: 0 3px 3px 0;
    background: var(--primary);
}

/* Icons */
.side-nav-icon {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    line-height: 1;
}

.side-nav-icon svg {
    width: 20px;
    height: 20px;
}

/* Labels */
.side-nav-label {
    transition: opacity var(--side-nav-transition);
    overflow: hidden;
}

/* Notification badge — absolute on icon, doesn't affect layout */
.side-nav-link {
    position: relative;
}

.side-nav-badge {
    position: absolute;
    top: 4px;
    left: 28px;
    background: var(--error);
    color: var(--text-inverse);
    font-size: 0.5625rem;
    font-weight: 700;
    min-width: 16px;
    height: 16px;
    line-height: 16px;
    text-align: center;
    border-radius: 100px;
    padding: 0 4px;
    flex-shrink: 0;
    transition: opacity var(--side-nav-transition);
    pointer-events: none;
    z-index: 1;
}

/* --------------------------------------------------------------------------
   Footer area (Settings, Help, User)
   -------------------------------------------------------------------------- */
.side-nav-footer {
    margin-top: auto;
    flex-shrink: 0;
    border-top: 1px solid var(--border-light);
}

/* User row */
.side-nav-user {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    padding: 0.75rem 1rem;
    border-top: 1px solid var(--border-light);
    overflow: hidden;
    white-space: nowrap;
}

.side-nav-user-avatar {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-light);
    color: var(--primary-dark);
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 0.8125rem;
    border-radius: 50%;
}

.side-nav-user>.side-nav-label {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.side-nav-logout {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    margin-left: auto;
    color: var(--text-secondary);
    border-radius: var(--border-radius-sm);
    flex-shrink: 0;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.side-nav-logout:hover {
    background: var(--error-bg);
    color: var(--error);
}

.side-nav-logout:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* --------------------------------------------------------------------------
   Collapsed state (desktop)
   -------------------------------------------------------------------------- */
.side-nav.collapsed {
    width: var(--side-nav-collapsed-width);
}

.side-nav.collapsed .side-nav-logo-text,
.side-nav.collapsed .side-nav-group-label,
.side-nav.collapsed .side-nav-label {
    opacity: 0;
    pointer-events: none;
}

/* Badge stays visible on icon when collapsed (small dot indicator) */
.side-nav.collapsed .side-nav-badge {
    top: 2px;
    left: 22px;
    min-width: 8px;
    height: 8px;
    font-size: 0;
    padding: 0;
    line-height: 0;
}

.side-nav.collapsed .side-nav-toggle .toggle-chevron {
    transform: rotate(180deg);
}

/* Pin icon not needed when fully collapsed (no peek) */
.side-nav.collapsed .toggle-pin {
    display: none;
}

.side-nav.collapsed .toggle-chevron {
    display: block;
}

.side-nav.collapsed .side-nav-header {
    justify-content: center;
    padding: 1rem 0.5rem;
}

.side-nav.collapsed .side-nav-logo {
    justify-content: center;
}

.side-nav.collapsed .side-nav-link {
    justify-content: center;
    padding: 0.5rem;
}

.side-nav.collapsed .side-nav-user {
    justify-content: center;
    padding: 0.75rem 0.5rem;
}

.side-nav.collapsed .side-nav-logout {
    display: none;
}

/* Tooltip on hover when collapsed */
.side-nav.collapsed .side-nav-link[aria-label]:hover::after,
.side-nav.collapsed .side-nav-link:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    left: calc(var(--side-nav-collapsed-width) + 4px);
    top: 50%;
    transform: translateY(-50%);
    background: var(--text-color);
    color: var(--text-inverse);
    font-size: 0.75rem;
    font-weight: 500;
    padding: 0.375rem 0.75rem;
    border-radius: var(--border-radius-sm);
    white-space: nowrap;
    z-index: 200;
    pointer-events: none;
    box-shadow: var(--shadow-md);
}

/* Hover-to-expand (peek) — temporarily show full width on hover */
.side-nav.collapsed:hover {
    width: var(--side-nav-width);
    box-shadow: var(--shadow-lg);
    transition-delay: 0.2s;
}

.side-nav.collapsed:hover .side-nav-logo-text,
.side-nav.collapsed:hover .side-nav-group-label,
.side-nav.collapsed:hover .side-nav-label {
    opacity: 1;
    pointer-events: auto;
    transition-delay: 0.2s;
}

/* Keep badge hidden during peek — icon dot is enough */
.side-nav.collapsed:hover .side-nav-badge {
    opacity: 0;
}

/* During peek: show pin icon, hide chevron */
.side-nav.collapsed:hover .side-nav-toggle {
    /* no transform on button */
}

.side-nav.collapsed:hover .toggle-chevron {
    display: none;
}

.side-nav.collapsed:hover .toggle-pin {
    display: block;
}

.side-nav.collapsed:hover .side-nav-header {
    justify-content: space-between;
    padding: 1rem;
}

.side-nav.collapsed:hover .side-nav-logo {
    justify-content: flex-start;
}

.side-nav.collapsed:hover .side-nav-link {
    justify-content: flex-start;
    padding: 0.5rem 0.75rem;
}

.side-nav.collapsed:hover .side-nav-user {
    justify-content: flex-start;
    padding: 0.75rem 1rem;
}

.side-nav.collapsed:hover .side-nav-logout {
    display: flex;
}

/* Hide tooltips during peek (full labels are visible) */
.side-nav.collapsed:hover .side-nav-link:hover::after {
    display: none;
}

/* --------------------------------------------------------------------------
   Main content offset
   -------------------------------------------------------------------------- */
.app-layout {
    display: flex;
    flex-direction: column;
    margin-left: var(--side-nav-width);
    transition: margin-left var(--side-nav-transition);
    min-height: 100vh;
    min-height: 100dvh;
}

.app-layout.nav-collapsed {
    margin-left: var(--side-nav-collapsed-width);
}

/* --------------------------------------------------------------------------
   Mobile top bar — visible < 1024px when side nav is hidden
   -------------------------------------------------------------------------- */
.mobile-top-bar {
    display: none;
    /* hidden on desktop, shown via media query */
    position: sticky;
    top: 0;
    z-index: 90;
    background: var(--card-background);
    border-bottom: 1px solid var(--border-color);
    padding: calc(0.75rem + env(safe-area-inset-top, 0px)) 1rem 0.75rem 1rem;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    min-height: 56px;
}

.mobile-top-bar .side-nav-logo {
    font-size: 1.125rem;
}

.mobile-top-bar-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Notification bell in mobile top bar */
.mobile-notification-link {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    color: var(--text-color);
    border-radius: var(--border-radius-sm);
}

.mobile-notification-link:hover {
    background: var(--primary-light);
}

.mobile-notification-badge {
    position: absolute;
    top: 4px;
    right: 4px;
    background: var(--error);
    color: var(--text-inverse);
    font-size: 0.6rem;
    font-weight: 700;
    min-width: 14px;
    height: 14px;
    line-height: 14px;
    text-align: center;
    border-radius: 50%;
    padding: 0 3px;
}

/* --------------------------------------------------------------------------
   Mobile bottom nav bar — visible < 1024px
   -------------------------------------------------------------------------- */
.mobile-bottom-nav {
    display: none;
    /* shown via media query */
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: var(--card-background);
    border-top: 1px solid var(--border-color);
    padding-bottom: env(safe-area-inset-bottom, 0);
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.06);
    align-items: stretch;
    justify-content: space-around;
}

.mobile-bottom-nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    gap: 2px;
    min-height: 56px;
    padding: 6px 4px 4px;
    background: none;
    border: none;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.6875rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    cursor: pointer;
    transition: color 0.15s ease, background 0.15s ease;
    -webkit-tap-highlight-color: transparent;
}

.mobile-bottom-nav-item:hover {
    color: var(--primary);
    background: var(--primary-light);
}

.mobile-bottom-nav-item:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: -2px;
    border-radius: var(--border-radius-sm);
}

.mobile-bottom-nav-item.active {
    color: var(--primary);
    font-weight: 600;
}

.mobile-bottom-nav-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
}

.mobile-bottom-nav-icon svg {
    width: 20px;
    height: 20px;
}

.mobile-bottom-nav-label {
    line-height: 1;
}

/* --------------------------------------------------------------------------
   Mobile overlay nav
   -------------------------------------------------------------------------- */
.mobile-nav-overlay {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 200;
    background: rgba(35, 40, 32, 0.5);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    opacity: 0;
    transition: opacity 0.25s ease;
}

.mobile-nav-overlay.open {
    display: block;
    opacity: 1;
}

.mobile-nav-drawer {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: min(300px, 85vw);
    background: var(--card-background);
    z-index: 201;
    display: flex;
    flex-direction: column;
    transform: translateX(-100%);
    transition: transform 0.25s ease;
    box-shadow: var(--shadow-lg);
    overflow-y: auto;
}

.mobile-nav-overlay.open+.mobile-nav-drawer,
.mobile-nav-drawer.open {
    transform: translateX(0);
}

.mobile-nav-drawer .side-nav-header {
    border-bottom: 1px solid var(--border-light);
}

.mobile-nav-drawer .side-nav-toggle {
    display: none;
}

/* Close button in drawer */
.mobile-nav-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    margin-left: auto;
}

.mobile-nav-close:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.mobile-nav-close:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

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

/* Mobile: hide side nav, show mobile top bar + bottom nav */
@media (max-width: 1023px) {
    .side-nav {
        display: none;
    }

    .app-layout {
        margin-left: 0;
        padding-bottom: calc(56px + env(safe-area-inset-bottom, 0px));
    }

    .app-layout.nav-collapsed {
        margin-left: 0;
    }

    .mobile-top-bar {
        display: flex;
    }

    .mobile-bottom-nav {
        display: flex;
    }
}

/* Medium screens: auto-collapse sidebar to icon-only */
@media (min-width: 1024px) and (max-width: 1279px) {
    .side-nav {
        width: var(--side-nav-collapsed-width);
    }

    .side-nav .side-nav-logo-text,
    .side-nav .side-nav-group-label,
    .side-nav .side-nav-label {
        opacity: 0;
        pointer-events: none;
    }

    .side-nav .side-nav-toggle .toggle-chevron {
        transform: rotate(180deg);
    }

    .side-nav .side-nav-header {
        justify-content: center;
        padding: 1rem 0.5rem;
    }

    .side-nav .side-nav-logo {
        justify-content: center;
    }

    .side-nav .side-nav-link {
        justify-content: center;
        padding: 0.5rem;
    }

    .side-nav .side-nav-user {
        justify-content: center;
        padding: 0.75rem 0.5rem;
    }

    .side-nav .side-nav-logout {
        display: none;
    }

    .side-nav .side-nav-badge {
        top: 2px;
        left: 22px;
        min-width: 8px;
        height: 8px;
        font-size: 0;
        padding: 0;
        line-height: 0;
    }

    .app-layout,
    .app-layout.nav-collapsed {
        margin-left: var(--side-nav-collapsed-width);
    }

    /* Hover-to-expand at medium screens too */
    .side-nav:hover {
        width: var(--side-nav-width);
        box-shadow: var(--shadow-lg);
        transition-delay: 0.2s;
    }

    .side-nav:hover .side-nav-logo-text,
    .side-nav:hover .side-nav-group-label,
    .side-nav:hover .side-nav-label {
        opacity: 1;
        pointer-events: auto;
        transition-delay: 0.2s;
    }

    .side-nav:hover .side-nav-badge {
        opacity: 0;
    }

    .side-nav:hover .side-nav-toggle {
        /* no transform on button */
    }

    .side-nav:hover .toggle-chevron {
        display: none;
    }

    .side-nav:hover .toggle-pin {
        display: block;
    }

    .side-nav:hover .side-nav-header {
        justify-content: space-between;
        padding: 1rem;
    }

    .side-nav:hover .side-nav-logo {
        justify-content: flex-start;
    }

    .side-nav:hover .side-nav-link {
        justify-content: flex-start;
        padding: 0.5rem 0.75rem;
    }

    .side-nav:hover .side-nav-user {
        justify-content: flex-start;
        padding: 0.75rem 1rem;
    }

    .side-nav:hover .side-nav-logout {
        display: flex;
    }

    /* Hide tooltips during hover-expand */
    .side-nav:hover .side-nav-link:hover::after {
        display: none;
    }
}

/* Desktop: hide mobile elements */
@media (min-width: 1024px) {
    .mobile-top-bar {
        display: none;
    }

    .mobile-bottom-nav {
        display: none;
    }

    .mobile-nav-overlay,
    .mobile-nav-drawer {
        display: none !important;
    }
}