/* ============================================================
   Layout System: Sidebar + Content
   PC: fixed left sidebar | Mobile: bottom tab bar
   ============================================================ */

.app-layout {
    display: flex;
    min-height: 100vh;
}

/* ============ Sidebar (PC) ============ */
.app-sidebar {
    width: 220px;
    background: var(--bg-card);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 100;
}

.sidebar-brand {
    padding: 24px 20px 20px;
    border-bottom: 1px solid var(--border-light);
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--text);
}
.sidebar-brand .brand-icon {
    width: 36px;
    height: 36px;
    background: var(--brand);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 14px;
    font-weight: 700;
    flex-shrink: 0;
}
.sidebar-brand .brand-text h1 {
    font-size: 15px;
    font-weight: 600;
    line-height: 1.2;
}
.sidebar-brand .brand-text span {
    font-size: 11px;
    color: var(--text-muted);
}

.sidebar-nav {
    flex: 1;
    padding: 12px 0;
    overflow-y: auto;
}
.sidebar-nav a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 20px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    transition: all var(--duration) var(--ease);
    border-left: 3px solid transparent;
    margin: 1px 0;
}
.sidebar-nav a:hover {
    background: var(--bg-warm);
    color: var(--text);
}
.sidebar-nav a.active {
    background: var(--brand-bg);
    color: var(--brand);
    border-left-color: var(--brand);
    font-weight: 600;
}
.sidebar-nav a svg {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}
.sidebar-nav .nav-divider {
    height: 1px;
    background: var(--border-light);
    margin: 8px 20px;
}

.sidebar-user {
    padding: 16px 20px;
    border-top: 1px solid var(--border-light);
}
.sidebar-user-info {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
}
.sidebar-user-avatar {
    width: 32px;
    height: 32px;
    background: var(--bg-warm);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 600;
    flex-shrink: 0;
}
.sidebar-user-name {
    font-size: 13px;
    font-weight: 500;
    color: var(--text);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.sidebar-user-points {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    color: var(--warning);
    font-weight: 600;
}
.sidebar-user-actions {
    display: flex;
    gap: 6px;
}
.sidebar-user-actions .btn {
    flex: 1;
    font-size: 11px;
    padding: 5px 8px;
}
.sidebar-login-prompt {
    text-align: center;
}
.sidebar-login-prompt a {
    display: block;
    padding: 10px;
    background: var(--brand);
    color: white;
    border-radius: var(--radius-sm);
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    transition: background var(--duration) var(--ease);
}
.sidebar-login-prompt a:hover {
    background: var(--brand-dark);
}

/* ============ Main Content Area ============ */
.app-main {
    flex: 1;
    margin-left: 220px;
    min-height: 100vh;
}

.page-toolbar {
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    padding: 0 40px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 50;
}
.page-toolbar h2 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text);
}
.page-toolbar-actions {
    display: flex;
    gap: 8px;
    align-items: center;
}

.page-content {
    padding: 32px 40px;
    max-width: 1400px;
}

/* ============ Mobile Bottom Tab Bar ============ */
.app-tabbar {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 56px;
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    z-index: 100;
    padding: 0;
}
.app-tabbar nav {
    display: flex;
    height: 100%;
}
.app-tabbar a {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2px;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 10px;
    font-weight: 500;
    transition: color var(--duration) var(--ease);
}
.app-tabbar a.active {
    color: var(--brand);
}
.app-tabbar a svg {
    width: 20px;
    height: 20px;
}

/* ============ Responsive ============ */
@media (max-width: 768px) {
    .app-sidebar { display: none; }
    .app-main { margin-left: 0; padding-bottom: 64px; }
    .app-tabbar { display: block; }
    .page-toolbar { padding: 0 16px; }
    .page-content { padding: 20px 16px; }
}