body, html {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    height: 100%;
    background-color: #f0f2f5;
}

#app {
    display: flex;
    height: 100%;
}

#sidebar {
    width: 300px;
    background-color: #2c3e50;
    color: white;
    padding: 20px;
    display: flex;
    flex-direction: column;
    box-shadow: 2px 0 5px rgba(0,0,0,0.1);
}

#sidebar-header {
    margin-bottom: 20px;
}

#sidebar-header h1 {
    font-size: 1.5em;
    margin-bottom: 15px;
    color: #ecf0f1;
}

#new-chat {
    width: 100%;
    padding: 12px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#new-chat:hover {
    background-color: #2980b9;
}

#chat-history {
    flex-grow: 1;
    overflow-y: auto;
}

#chat-history button {
    width: 100%;
    text-align: left;
    padding: 12px;
    margin-bottom: 8px;
    background-color: #34495e;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#chat-history button:hover {
    background-color: #2c3e50;
}

#chat-area {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    background-color: #ecf0f1;
}

#chat-header {
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: #3498db;
    color: white;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

#who-are-you {
    padding: 10px 15px;
    background-color: #e74c3c;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#who-are-you:hover {
    background-color: #c0392b;
}

#chat-messages {
    flex-grow: 1;
    overflow-y: auto;
    padding: 20px;
}

.message {
    margin-bottom: 15px;
    padding: 12px;
    border-radius: 10px;
    max-width: 70%;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.user-message {
    background-color: #3498db;
    color: white;
    align-self: flex-end;
    margin-left: auto;
}

.ai-message {
    background-color: #2ecc71;
    color: white;
    align-self: flex-start;
}

#chat-input-area {
    display: flex;
    padding: 20px;
    background-color: #bdc3c7;
    align-items: center;
}

#user-input {
    flex-grow: 1;
    padding: 12px;
    margin-right: 10px;
    border: none;
    border-radius: 5px;
    font-size: 16px;
}

.custom-file-upload {
    display: inline-block;
    padding: 12px;
    cursor: pointer;
    background-color: #95a5a6;
    color: white;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

.custom-file-upload:hover {
    background-color: #7f8c8d;
}

#image-upload {
    display: none;
}

button {
    padding: 12px 20px;
    background-color: #e74c3c;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    font-size: 16px;
}

button:hover {
    background-color: #c0392b;
}

/* Scrollbar Styles */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}