.app-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    height: 100vh;
    width: 100vw;
}

/* Sidebar */
.sidebar {
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    padding: var(--spacing-md);
    overflow-y: auto;
    transition: transform 0.3s ease;
    z-index: 10;
}

.sidebar-header {
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.sidebar-section {
    margin-bottom: var(--spacing-lg);
}

.sidebar-section h3 {
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-sm);
}

/* Main Chat Area */
.main-content {
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: relative;
    background: radial-gradient(circle at top right, rgba(0, 255, 157, 0.05), transparent 40%);
}

.chat-history {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-lg);
    padding-bottom: 120px;
    /* Space for input */
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    scroll-behavior: smooth;
}

.input-area {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-lg);
    background: linear-gradient(to top, var(--bg-primary) 80%, transparent);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    z-index: 5;
}

/* Mobile Layout */
@media (max-width: 768px) {
    .app-container {
        grid-template-columns: 1fr;
    }

    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        width: 280px;
        transform: translateX(-100%);
        box-shadow: var(--shadow-md);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .mobile-menu-toggle {
        display: block;
        position: absolute;
        top: var(--spacing-md);
        left: var(--spacing-md);
        z-index: 20;
    }
}