/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

:root {
    /* 亮色主题变量 */
    --primary-color: #4682B4;
    --secondary-color: #5F9EA0;
    --background-color: #F5F5F7;
    --card-bg: #FFFFFF;
    --text-color: #333333;
    --text-secondary: #666666;
    --border-color: #E0E0E0;
    --sent-bubble: #DCF8C6;
    --received-bubble: #FFFFFF;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --input-bg: #FFFFFF;
    --typing-indicator-bg: #f0f0f0;
}

.dark-theme {
    /* 暗色主题变量 */
    --primary-color: #5F9EA0;
    --secondary-color: #6CA6CD;
    --background-color: #121212;
    --card-bg: #1E1E1E;
    --text-color: #E0E0E0;
    --text-secondary: #A0A0A0;
    --border-color: #2D2D2D;
    --sent-bubble: #2B5278;
    --received-bubble: #2D2D2D;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --input-bg: #2D2D2D;
    --typing-indicator-bg: #2a2a2a;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    height: 100vh;
    overflow: hidden;
}

/* 应用布局 */
.app-container {
    display: flex;
    height: 100vh;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

/* 聊天容器样式 */
.chat-container {
    width: 100%;
    max-width: 500px;
    height: 100%;
    max-height: 700px;
    display: flex;
    flex-direction: column;
    background-color: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 4px 20px var(--shadow-color);
    overflow: hidden;
    position: relative;
}

.chat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--card-bg);
}

.contact-info {
    display: flex;
    align-items: center;
}

.contact-info .avatar {
    margin-right: 12px;
}

.contact-details h2 {
    font-size: 16px;
    font-weight: 600;
}

.contact-details p {
    font-size: 12px;
    color: var(--text-secondary);
}

.header-actions {
    display: flex;
    align-items: center;
}

.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 20px;
    padding: 4px;
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
}

.theme-toggle:hover {
    background-color: var(--border-color);
}

/* 消息区域样式 */
.chat-messages {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
    background-color: var(--background-color);
}

.message {
    display: flex;
    max-width: 80%;
}

.message.received {
    align-self: flex-start;
}

.message.sent {
    align-self: flex-end;
    flex-direction: row-reverse;
}

.message-content {
    padding: 10px 14px;
    border-radius: 18px;
    font-size: 14px;
    line-height: 1.4;
    position: relative;
    max-width: 100%;
}

.received .message-content {
    background-color: var(--received-bubble);
    border-top-left-radius: 4px;
    color: var(--text-color);
    margin-left: 8px;
}

.sent .message-content {
    background-color: var(--sent-bubble);
    border-top-right-radius: 4px;
    color: var(--text-color);
}

.message-time {
    font-size: 10px;
    color: var(--text-secondary);
    margin-top: 4px;
    text-align: right;
}

.sent .message-time {
    text-align: left;
}

/* 输入区域样式 */
.chat-input-container {
    padding: 16px;
    border-top: 1px solid var(--border-color);
    background-color: var(--card-bg);
    display: flex;
    align-items: center;
    gap: 8px;
}

.chat-input {
    flex: 1;
}

#message-input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    background-color: var(--input-bg);
    color: var(--text-color);
    outline: none;
    font-size: 14px;
}

#message-input:focus {
    border-color: var(--primary-color);
}

.send-btn {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px;
    border-radius: 50%;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.send-btn:hover {
    background-color: var(--secondary-color);
}

.send-btn:disabled {
    background-color: var(--border-color);
    cursor: not-allowed;
}

/* 输入指示器 */
.chat-typing-indicator {
    display: none;
    padding: 10px 16px;
    background-color: var(--typing-indicator-bg);
    align-items: center;
    gap: 8px;
}

.chat-typing-indicator.active {
    display: flex;
}

.typing-dots {
    display: flex;
    align-items: center;
    height: 20px;
}

.typing-dots span {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background-color: var(--text-secondary);
    margin: 0 1px;
    display: inline-block;
    animation: typing-dots 1.4s infinite ease-in-out both;
}

.typing-dots span:nth-child(1) {
    animation-delay: -0.32s;
}

.typing-dots span:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes typing-dots {
    0%, 80%, 100% { 
        transform: scale(0.8);
        opacity: 0.5;
    }
    40% { 
        transform: scale(1);
        opacity: 1;
    }
}

.chat-typing-indicator p {
    font-size: 12px;
    color: var(--text-secondary);
}

/* 头像样式 */
.avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
    flex-shrink: 0;
}

.message .avatar {
    width: 36px;
    height: 36px;
    align-self: flex-end;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .app-container {
        padding: 10px;
    }
    
    .chat-container {
        max-height: 100%;
        border-radius: 0;
    }
    
    .message {
        max-width: 85%;
    }
}

@media (max-width: 480px) {
    .chat-header {
        padding: 12px;
    }
    
    .chat-messages {
        padding: 12px;
    }
    
    .chat-input-container {
        padding: 12px;
    }
    
    .message {
        max-width: 90%;
    }
}

/* 滚动条样式 */
.chat-messages::-webkit-scrollbar {
    width: 5px;
}

.chat-messages::-webkit-scrollbar-track {
    background: transparent;
}

.chat-messages::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 10px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background-color: var(--text-secondary);
}