.sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    z-index: 40;
    display: flex;
    width: 280px;
    min-width: 280px;
    flex-direction: column;
    border-right: 1px solid var(--sidebar-border, hsl(var(--border)));
    background: var(--sidebar-background, hsl(var(--background)));
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 14px;
    line-height: 1.4;
}

.sidebar.hidden,
.sidebar-collapsed-strip.hidden { display: none; }

.sidebar-top-section {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: .25rem;
    padding: 1rem 2rem .25rem;
}

.sidebar-brand-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: .25rem;
}

.sidebar-brand {
    padding: .25rem .5rem;
    color: var(--sidebar-foreground, hsl(var(--foreground)));
    font: 600 2rem/1 ui-serif, Georgia, "Times New Roman", serif;
    letter-spacing: -.01em;
    text-decoration: none;
}

.sidebar-brand:hover { opacity: .85; }

.sidebar-nav-item {
    display: flex;
    align-items: center;
    gap: .875rem;
    width: 100%;
    padding: .75rem;
    border: 0;
    border-radius: .5rem;
    background: transparent;
    color: var(--sidebar-foreground, hsl(var(--foreground)));
    cursor: pointer;
    font-size: 1.125rem;
    font-weight: 600;
    line-height: 1.4rem;
    text-align: left;
    text-decoration: none;
    transition: background-color .15s ease, color .15s ease;
}

.sidebar-nav-item:hover { background: var(--sidebar-accent, hsl(var(--accent))); }

.sidebar-nav-item .sidebar-nav-icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
    color: var(--sidebar-muted, hsl(var(--muted-foreground)));
}

.sidebar-nav-item:hover .sidebar-nav-icon {
    color: var(--sidebar-foreground, hsl(var(--foreground)));
}

.sidebar-bottom-section {
    display: flex;
    min-height: 0;
    flex: 1;
    flex-direction: column;
    margin-top: 0;
    padding: 0 2rem 1rem;
    border-top: 0;
}

.sidebar-bottom-section .sidebar-nav-item { margin-bottom: .25rem; }

.logout-btn {
    display: flex;
    align-items: center;
    margin-top: auto;
    gap: .875rem;
    width: 100%;
    padding: .75rem;
    border-radius: .375rem;
    color: var(--sidebar-muted, hsl(var(--muted-foreground)));
    font-size: 1.125rem;
    line-height: 1.4rem;
    text-decoration: none;
    transition: background-color .15s ease, color .15s ease;
}

.logout-btn:hover {
    background: var(--sidebar-accent, hsl(var(--accent)));
    color: var(--sidebar-foreground, hsl(var(--foreground)));
}

.logout-btn svg { width: 24px; height: 24px; }

.sidebar-collapsed-strip {
    position: fixed;
    inset: 0 auto 0 0;
    z-index: 40;
    display: flex;
    width: 60px;
    flex-direction: column;
    align-items: center;
    gap: .75rem;
    padding: 1rem 0;
    border-right: 1px solid var(--sidebar-border, hsl(var(--border)));
    background: var(--sidebar-background, hsl(var(--background)));
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 14px;
    line-height: 1.4;
}

.sidebar-icon-btn,
.new-chat-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    border: 0;
    cursor: pointer;
}

.sidebar-icon-btn {
    border-radius: .375rem;
    background: transparent;
    color: var(--sidebar-foreground, hsl(var(--foreground)));
    transition: background-color .15s ease;
}

.sidebar-icon-btn:hover { background: var(--sidebar-accent, hsl(var(--accent))); }

.sidebar-icon-btn svg,
.new-chat-btn svg { width: 20px; height: 20px; }

.sidebar-settings-link { margin-top: auto; }

.new-chat-btn {
    border-radius: 50%;
    background: var(--sidebar-primary, hsl(var(--primary)));
    color: var(--sidebar-primary-foreground, hsl(var(--primary-foreground)));
    text-decoration: none;
    transition: opacity .15s ease;
}

.new-chat-btn:hover { opacity: .85; }

.main-content,
.storefront-app {
    margin-left: 280px;
    transition: margin-left .2s ease;
}

.main-content { position: relative; }

.main-content.sidebar-collapsed,
.storefront-app.sidebar-collapsed { margin-left: 60px; }

@media (max-width: 768px) {
    .sidebar,
    .sidebar-collapsed-strip { display: none; }

    .sidebar.mobile-open,
    .sidebar-collapsed-strip.mobile-show { display: flex; }

    .main-content,
    .main-content.sidebar-collapsed,
    .storefront-app,
    .storefront-app.sidebar-collapsed { margin-left: 0; }
}