:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --background-color: #f5f7fa;
    --text-color: #333;
    --chat-bg: #fff;
}
.chat-container {
    background-color: var(--chat-bg);
    border-radius: 20px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    width: 400px;
    display: flex;
    flex-direction: column;
    height: 600px;
    margin: 20px auto;
}
.chat-header {
    background-color: var(--primary-color);
    color: white;
    padding: 20px;
    text-align: center;
    font-size: 1.2em;
    font-weight: bold;
}
.role-setting {
    background-color: var(--background-color);
    padding: 15px;
}
#ai-role {
    width: calc(100% - 22px);
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 20px;
    margin-bottom: 10px;
    font-size: 14px;
}
#set-role-button {
    width: 100%;
    background-color: var(--secondary-color);
    color: white;
    border: none;
    padding: 10px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}
#set-role-button:hover {
    background-color: #27ae60;
}
.chat-messages {
    flex-grow: 1;
    overflow-y: auto;
    padding: 20px;
}
.message {
    margin-bottom: 15px;
    clear: both;
    max-width: 80%;
    white-space: pre-wrap;
    word-wrap: break-word;
}
.user {
    float: right;
    background-color: var(--primary-color);
    color: white;
    border-radius: 18px 18px 0 18px;
    padding: 10px 15px;
}
.bot {
    float: left;
    background-color: #f1f3f5;
    color: var(--text-color);
    border-radius: 18px 18px 18px 0;
    padding: 10px 15px;
}
.chat-input {
    display: flex;
    padding: 15px;
    background-color: var(--background-color);
}
#user-input {
    flex-grow: 1;
    border: none;
    padding: 10px 15px;
    border-radius: 20px;
    margin-right: 10px;
    font-size: 14px;
}
#send-button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}
#send-button:hover {
    background-color: #2980b9;
}
.loading {
    text-align: center;
    margin: 20px 0;
    display: none;
}
.loading-spinner {
    display: inline-block;
    width: 50px;
    height: 50px;
    border: 3px solid rgba(0,0,0,.3);
    border-radius: 50%;
    border-top-color: #3498db;
    animation: spin 1s ease-in-out infinite;
}
@keyframes spin {
    to { transform: rotate(360deg); }
}
.loading-text {
    margin-top: 10px;
    font-size: 14px;
    color: #666;
}
.loading-dots::after {
    content: '...';
    animation: dots 1.5s steps(4, end) infinite;
}
@keyframes dots {
    0%, 20% { content: ''; }
    40% { content: '.'; }
    60% { content: '..'; }
    80%, 100% { content: '...'; }
}