/* Application Shell Layout */
#app {
    display: flex;
    height: 100vh;
    overflow: hidden;
    width: 100%;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background-color: var(--color-bg-base);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    padding: var(--spacing-6) var(--spacing-4);
    flex-shrink: 0;
    z-index: 10;
    transition: transform var(--transition-normal);
}

.brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    margin-bottom: var(--spacing-8);
    padding: 0 var(--spacing-2);
}

.brand-icon {
    width: 32px;
    height: 32px;
    background-color: var(--color-primary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
}

.brand-text h1 {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    line-height: 1.2;
}

.brand-text span {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Persona Switcher */
.persona-switcher {
    margin-bottom: var(--spacing-6);
}

.persona-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-3);
    background-color: var(--color-bg-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: background-color var(--transition-fast);
}

.persona-btn:hover {
    background-color: var(--color-bg-surface-hover);
}

.persona-info {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.persona-label {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
}

.persona-name {
    font-size: 0.875rem;
    font-weight: 600;
}

/* Navigation */
.nav-menu {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
    overflow-y: auto;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    padding: var(--spacing-3) var(--spacing-4);
    border-radius: var(--radius-md);
    color: var(--color-text-secondary);
    font-weight: 500;
    font-size: 0.9375rem;
    transition: all var(--transition-fast);
}

.nav-item:hover {
    color: var(--color-text-primary);
    background-color: var(--color-bg-surface);
}

.nav-item.active {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
    background-opacity: 0.1;
}

.nav-item.active {
    background-color: rgba(85, 51, 255, 0.1); /* fallback */
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: var(--color-bg-surface);
    overflow-y: auto;
    position: relative;
}

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-6) var(--spacing-8);
    background-color: transparent;
}

.page-title {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.025em;
}

.content-area {
    padding: 0 var(--spacing-8) var(--spacing-8);
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
}

/* Mobile Nav Toggle */
.mobile-nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--color-text-primary);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        transform: translateX(-100%);
    }

    .sidebar.open {
        transform: translateX(0);
        box-shadow: var(--shadow-lg);
    }

    .mobile-nav-toggle {
        display: block;
    }

    .header {
        padding: var(--spacing-4);
    }

    .content-area {
        padding: 0 var(--spacing-4) var(--spacing-4);
    }
}