.chat-history-pane {
    flex: 0 0 33%;
    background-color: var(--bg-chat-history-pane);
    padding: 15px;
    overflow-y: auto;
}

.main-pane {
    flex: 1;
    background-color: var(--bg-primary);
    padding: 20px;
    overflow: hidden;
}

/* Top Bar Styling */
.top-bar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80%;
    background-color: var(--bg-container);
    border-bottom: 1px solid var(--border-color);
    align-items: center;
    padding: 0 10px;
    z-index: 1000;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    visibility: hidden;
}

/* Left Section: Logo and Buttons */
.top-bar-left {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Blueprint Metadata Centered */
.blueprint-metadata {
    flex: 1;
    text-align: center;
    font-size: 0.85rem;
}

/* Right Section: Settings Button */
.top-bar-right {
    margin-left: auto;
    display: flex;
    align-items: center;
}

/* Buttons in the Top Bar */
.top-bar-btn {
    background: none;
    border: none;
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 5px 10px;
    font-size: 0.85rem;
    cursor: pointer;
    color: var(--text-color);
    text-decoration: none;
    white-space: nowrap;
    flex-shrink: 0;
    transition: background-color 0.2s ease, color 0.2s ease;
}

.top-bar-btn img {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.top-bar-btn:hover {
    background-color: var(--button-hover-bg);
}

.top-bar-btn .btn-label {
    display: inline-block;
    white-space: nowrap;
    visibility: visible;
}

/* Main Chat Pane */
.main-pane {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-sizing: border-box;
}

/* Message Input Area */
.message-input-container {
    display: flex;
    align-items: center;
    gap: 10px;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    position: absolute;
    bottom: 0;
    width: 100%;
}

/* Vertical Divider for Resizing */
.vertical-divider {
    width: 10px;
    cursor: col-resize;
    background-color: var(--border-color);
    opacity: 0;
    transition: opacity 0.2s ease, background-color 0.2s ease;
}

.vertical-divider:hover {
    opacity: 1;
    background-color: var(--button-hover-bg);
}

/* Sidebar Reveal Buttons */
.sidebar-reveal-btn {
    position: absolute;
    top: 10px; /* Adjusted to be higher */
    z-index: 1000;
    background-color: var(--button-primary);
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    transition: background-color var(--transition-duration) ease;
    font-size: 1em;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0.6; /* Dimmed */
}

.sidebar-reveal-btn:hover {
    opacity: 1; /* Fully visible on hover */
}

.sidebar-reveal-btn + .sidebar-reveal-btn {
    top: 60px; /* Reduced gap */
    opacity: 0.6;
}

.sidebar-reveal-btn:hover + .sidebar-reveal-btn {
    opacity: 1;
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    .message-input-container {
        flex-direction: column;
        gap: 5px;
    }
}

.hidden {
    display: none !important;
}

.visible {
    display: block;
}
