/* Custom Color Palette */
        :root {
            --primary-color: #00796B; /* A deep teal that complements maps */
            --primary-light: #E0F2F1;
            --background-color: #F5F7FA;
            --chat-panel-bg: #FFFFFF;
            --user-bubble-bg: #E3F2FD; /* A soft blue for the user */
            --bot-bubble-bg: #E8F5E9;  /* A soft green for the bot */
            --text-primary: #212121;
            --text-secondary: #757575;
            --border-color: #E0E0E0;
        }

        body.dark-mode {
            --primary-color: #4DB6AC;
            --primary-light: #26A69A;
            --background-color: #121212;
            --chat-panel-bg: #1E1E1E;
            --user-bubble-bg: #2C3E50;
            --bot-bubble-bg: #34495E;
            --text-primary: #EAEAEA;
            --text-secondary: #BDBDBD;
            --border-color: #424242;
            --marker-color: #EF5350;
        }

        /* General Styling */
        html { box-sizing: border-box; }
        *, *:before, *:after { box-sizing: inherit; }
        body {
            font-family: 'Inter', sans-serif;
            margin: 0;
            padding: 0;
            background-color: var(--background-color);
            display: flex;
            flex-direction: row; /* Default for desktop: chat and map side-by-side */
            height: 100vh;
            overflow: hidden;
            transition: background-color 0.3s, color 0.3s;
        }

        /* Layout Containers */
        .chat-container {
            width: 35%;
            max-width: 450px;
            min-width: 320px;
            height: 100vh; /* Full height on desktop */
            background-color: var(--chat-panel-bg);
            display: flex;
            flex-direction: column;
            box-shadow: 0 0 25px rgba(0,0,0,0.05);
            border-right: 1px solid var(--border-color);
            position: relative;
            transition: min-width 0.3s ease-in-out, width 0.3s ease-in-out, padding 0.3s ease-in-out, background-color 0.3s;
        }
        #map {
            flex-grow: 1;
            height: 100vh; /* Full height on desktop */
            transition: width 0.3s ease-in-out;
        }

        /* Collapsed State */
        .chat-container.collapsed {
            width: 0;
            min-width: 0;
            padding: 0;
            border-right: none;
        }
        .chat-container.collapsed > *:not(#collapse-btn) { visibility: hidden; }
        .chat-container.collapsed #collapse-btn { visibility: visible; }

        /* Chat Header */
        .chat-header {
            padding: 1rem 1.5rem;
            background-color: var(--chat-panel-bg);
            border-bottom: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            gap: 0.75rem;
            flex-shrink: 0;
            transition: background-color 0.3s, border-color 0.3s;
        }
        .chat-header h1 {
            margin: 0;
            font-family: 'Poppins', sans-serif;
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--primary-color);
            transition: color 0.3s;
        }
        
        /* Control Buttons: Collapse and Theme */
        #collapse-btn, #theme-toggle-btn {
            background: var(--chat-panel-bg);
            border: 1px solid var(--border-color);
            border-radius: 50%;
            width: 32px;
            height: 32px;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: all 0.3s ease-in-out;
            position: absolute;
            top: 20px;
            z-index: 10;
            color: var(--text-secondary);
        }

        #collapse-btn {
            right: 10px;
        }

        #theme-toggle-btn {
            right: 52px; /* Positioned to the left of collapse button */
        }
        
        #collapse-btn:hover, #theme-toggle-btn:hover { 
            transform: scale(1.1);
            background-color: var(--background-color);
        }
        
        #collapse-btn svg, #theme-toggle-btn svg { 
            width: 20px; 
            height: 20px; 
            transition: transform 0.3s ease-in-out; 
        }

        /* Theme Toggle Icon Visibility */
        body.dark-mode .sun-icon { display: none; }
        body:not(.dark-mode) .moon-icon { display: none; }

        /* Desktop collapse state */
        .chat-container.collapsed #collapse-btn {
            right: auto;
            left: 10px;
            box-shadow: 0 0 10px rgba(0,0,0,0.1);
        }
        .chat-container.collapsed #collapse-btn svg {
            transform: rotate(180deg);
        }
        .chat-container.collapsed #theme-toggle-btn {
            visibility: hidden;
        }

        /* Chat Messages Area */
        .messages {
            flex: 1;
            padding: 1.5rem;
            overflow-y: auto;
            background-color: var(--background-color);
            transition: background-color 0.3s;
        }
        #messages-container { display: flex; flex-direction: column; gap: 1.25rem; }
        .messages::-webkit-scrollbar { width: 6px; }
        .messages::-webkit-scrollbar-track { background: transparent; }
        .messages::-webkit-scrollbar-thumb { background: #d1d5db; border-radius: 10px; }
        body.dark-mode .messages::-webkit-scrollbar-thumb { background: #555; }


        /* Individual Messages & Input Area */
        .message-wrapper { 
            display: flex; 
            flex-direction: column; 
            max-width: 90%; 
            position: relative;
        }
        .message-wrapper.user { align-self: flex-end; align-items: flex-end; }
        .message-wrapper.bot { align-self: flex-start; align-items: flex-start; }

        .message-sender {
            font-size: 0.8rem;
            font-weight: 600;
            color: var(--text-secondary);
            margin: 0 0 0.25rem 0;
            padding: 0 0.5rem;
        }

        .message-bubble { 
            line-height: 1.5; 
            padding: 0.75rem 1rem; 
            border-radius: 1rem;
            width: fit-content;
            transition: background-color 0.3s;
        }
        .message-bubble.bot { background-color: var(--bot-bubble-bg); border-top-left-radius: 0; }
        .message-bubble.user { background-color: var(--user-bubble-bg); border-top-right-radius: 0; }

        .message-text { font-size: 1rem; font-weight: 400; color: var(--text-primary); margin: 0; }

        /* Controls for TTS */
        .message-controls {
            display: flex;
            align-items: center;
            gap: 4px;
            margin-top: 4px;
            margin-left: 4px;
        }
        .speaker-btn, .stop-btn {
            background: none;
            border: none;
            cursor: pointer;
            padding: 4px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-secondary);
            opacity: 0.6;
            transition: opacity 0.2s, color 0.2s;
        }
        .speaker-btn:hover, .stop-btn:hover {
            opacity: 1;
            color: var(--primary-color);
        }
        .speaker-btn svg, .stop-btn svg {
            width: 16px;
            height: 16px;
        }

        /* Input area layout */
        .input-area { 
            padding: 1rem 1.5rem; 
            background-color: var(--chat-panel-bg); 
            border-top: 1px solid var(--border-color); 
            display: flex; 
            align-items: center; 
            gap: 0.5rem;
            flex-shrink: 0; 
            transition: background-color 0.3s, border-color 0.3s;
        }
        #userInput { 
            flex-grow: 1; 
            flex-shrink: 1; 
            min-width: 50px;
            padding: 0.75rem 1rem; 
            border: 1px solid var(--border-color); 
            border-radius: 9999px; 
            transition: box-shadow 0.2s, border-color 0.2s, background-color 0.3s, color 0.3s;
            font-size: 1rem; 
            background-color: var(--background-color);
            color: var(--text-primary);
        }
        #userInput:focus { 
            outline: none; 
            box-shadow: 0 0 0 3px var(--primary-light); 
            border-color: var(--primary-color); 
        }

        /* BUTTON STYLES (Send, Mic, 3D) */
        .send-button, #mic-btn, #threed-btn { 
            flex-shrink: 0; 
            width: 48px; 
            height: 48px; 
            color: white; 
            border-radius: 50%; 
            border: none; 
            cursor: pointer; 
            transition: background-color 0.3s, box-shadow 0.3s; 
            display: flex; 
            align-items: center; 
            justify-content: center; 
        }

        .send-button {
            background-color: var(--primary-color); 
        }
        .send-button:hover { background-color: #004D40; }
        body.dark-mode .send-button:hover { background-color: #80CBC4; }
        .send-button svg { width: 24px; height: 24px; }

        #mic-btn {
            background-color: #8D6E63;
        }
        #mic-btn:hover {
            background-color: #6D4C41;
        }
        #mic-btn.listening {
            background-color: #D32F2F; 
            animation: pulse 1.5s infinite;
            box-shadow: 0 0 0 0 rgba(211, 47, 47, 0.7);
        }

        @keyframes pulse {
            0% { box-shadow: 0 0 0 0 rgba(211, 47, 47, 0.7); }
            70% { box-shadow: 0 0 0 10px rgba(211, 47, 47, 0); }
            100% { box-shadow: 0 0 0 0 rgba(211, 47, 47, 0); }
        }

        #threed-btn {
            background-color: #607D8B;
            font-family: 'Poppins', sans-serif;
            font-weight: 600;
            font-size: 1rem;
            text-decoration: none;
        }

        #threed-btn:hover {
            background-color: #455A64;
        }

        .thinking-bubble::after { content: '...'; display: inline-block; animation: thinking 1.5s infinite; }
        @keyframes thinking { 0% { content: '.'; } 33% { content: '..'; } 66% { content: '...'; } 100% { content: '.'; } }

        /* Media Queries for Responsiveness */
        @media (max-width: 768px) {
            body {
                flex-direction: column;
                overflow-y: auto;
            }

            .chat-container {
                width: 100%;
                max-width: none;
                min-width: unset;
                height: 60vh;
                border-right: none;
                border-bottom: 1px solid var(--border-color);
                box-shadow: 0 5px 15px rgba(0,0,0,0.05);
                order: 1;
            }

            #map {
                width: 100%;
                height: 40vh;
                order: 2;
            }

            #collapse-btn, #theme-toggle-btn {
                top: 10px;
            }
            #collapse-btn { right: 10px; }
            #theme-toggle-btn { right: 52px; }

            #collapse-btn svg {
                transform: rotate(270deg); /* Arrow points down */
            }

            .chat-container.collapsed {
                height: 50px;
                width: 100%;
                min-height: unset;
                padding: 0;
                border-bottom: 1px solid var(--border-color);
                overflow: hidden;
            }

            .chat-container.collapsed #collapse-btn {
                right: 10px;
                left: auto;
                top: 10px;
                box-shadow: none;
            }

            .chat-container.collapsed #collapse-btn svg {
                transform: rotate(90deg); /* Arrow points up */
            }
            
            .chat-container.collapsed #theme-toggle-btn {
                visibility: visible; /* Ensure it's visible on mobile collapsed view */
            }

            .chat-container.collapsed .chat-header {
                visibility: visible;
                display: flex;
                align-items: center;
                justify-content: space-between;
                padding: 0.5rem 1.5rem;
            }
            
            .chat-container.collapsed .chat-header h1 {
                font-size: 1.2rem;
            }


            .chat-container.collapsed .messages,
            .chat-container.collapsed .input-area {
                display: none;
            }

            .chat-header h1 {
                flex-grow: 1;
            }
        }

        @media (max-width: 480px) {
            .chat-header h1 {
                font-size: 1.3rem;
            }

            .input-area {
                padding: 0.75rem 1rem;
                gap: 0.5rem;
            }

            #userInput {
                padding: 0.6rem 0.9rem;
                font-size: 0.9rem;
            }

            .send-button, #mic-btn, #threed-btn {
                width: 40px;
                height: 40px;
            }
            .send-button svg {
                width: 20px;
                height: 20px;
            }

            #threed-btn {
                padding: 0;
                font-size: 0.9rem;
            }
        }