/* 引入一个更具科技感的字体 */
@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400&display=swap');

/* --- 基础与背景 --- */
body, html {
    margin: 0;
    padding: 0;
    height: 100%;
    width: 100%;
    overflow: hidden;
    font-family: 'Roboto', -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
    /* 使用深邃的径向渐变作为静态背景 */
    background: radial-gradient(ellipse at center, #1b2735 0%, #090a0f 100%);
    display: flex;
    justify-content: center;
    align-items: center;
}

/* --- 聊天窗口 --- */
#chat-window {
    width: 90%;
    max-width: 700px;
    height: 85vh;
    background: rgba(13, 27, 42, 0.8);
    border: 1px solid rgba(57, 255, 220, 0.3);
    border-radius: 12px;
    backdrop-filter: blur(15px);
    z-index: 10;
    display: flex;
    flex-direction: column;
    box-sizing: border-box;
    box-shadow: 0 0 35px rgba(0, 0, 0, 0.7), inset 0 0 20px rgba(57, 255, 220, 0.1);
    overflow: hidden;
    /* --- 新增的动画属性 --- */
    animation: breathing-glow 5s ease-in-out infinite;
}

/* --- 聊天窗口头部 --- */
#chat-header {
    padding: 15px 25px;
    border-bottom: 1px solid rgba(57, 255, 220, 0.2);
    flex-shrink: 0;
}

.title {
    color: #e0fbfc;
    font-size: 1.8rem;
    font-weight: 300;
    text-align: center;
    margin: 0;
    text-shadow: 0 0 10px rgba(57, 255, 220, 0.5);
}

/* --- 消息显示区域 --- */
#chat-messages {
    flex-grow: 1;
    overflow-y: auto;
    color: #e0fbfc;
    display: flex;
    flex-direction: column;
    gap: 15px;
    padding: 20px 25px;
}

.message { 
    padding: 12px 18px; 
    border-radius: 8px; 
    max-width: 85%; 
    word-wrap: break-word; 
    line-height: 1.6;
    font-weight: 300;
    border: 1px solid transparent;
}

.user-message { 
    background-color: rgba(57, 185, 255, 0.1); 
    border-color: rgba(57, 185, 255, 0.3);
    color: #d1faff; 
    align-self: flex-end; 
    border-bottom-right-radius: 2px; 
}

.assistant-message {
    background-color: transparent; 
    color: #e0fbfc; 
    align-self: flex-start; 
    border-bottom-left-radius: 2px;
    border: 1px solid rgba(57, 255, 220, 0.2);
}

/* --- 输入区域 --- */
#chat-input-container { 
    display: flex; 
    gap: 10px; 
    flex-shrink: 0; 
    align-items: center;
    padding: 20px 25px;
    border-top: 1px solid rgba(57, 255, 220, 0.2);
}

#chat-input {
    flex-grow: 1;
    padding: 14px;
    border: 1px solid rgba(57, 255, 220, 0.3);
    border-radius: 6px;
    background-color: rgba(0, 0, 0, 0.3);
    color: #e0fbfc;
    font-size: 1rem;
    transition: border-color 0.3s, box-shadow 0.3s;
    min-width: 0;
}

#chat-input::placeholder { color: rgba(224, 251, 252, 0.4); }
#chat-input:focus { 
    outline: none; 
    border-color: #39ffd8; 
    box-shadow: 0 0 12px rgba(57, 255, 220, 0.4); 
}

#send-button {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    padding: 0;
    font-size: 1.3rem;
    cursor: pointer;
    background-color: rgba(57, 255, 220, 0.1);
    color: #e0fbfc;
    border: 1px solid rgba(57, 255, 220, 0.3);
    border-radius: 6px;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
}
#send-button:hover { 
    background-color: rgba(57, 255, 220, 0.3);
    box-shadow: 0 0 10px rgba(57, 255, 220, 0.3);
}
#send-button:active { transform: scale(0.95); }
#send-button:disabled { opacity: 0.4; cursor: not-allowed; background-color: transparent; }

/* --- 美化滚动条 --- */
#chat-messages::-webkit-scrollbar { width: 8px; }
#chat-messages::-webkit-scrollbar-track { background: transparent; }
#chat-messages::-webkit-scrollbar-thumb { background-color: rgba(57, 255, 220, 0.2); border-radius: 4px; }
#chat-messages::-webkit-scrollbar-thumb:hover { background-color: rgba(57, 255, 220, 0.5); }


/* --- 呼吸辉光动画 --- */
@keyframes breathing-glow {
    0% {
        border-color: rgba(57, 255, 220, 0.3);
        box-shadow: 0 0 35px rgba(0, 0, 0, 0.7), 
                    inset 0 0 20px rgba(57, 255, 220, 0.1),
                    0 0 15px rgba(57, 255, 220, 0.1); /* 新增外部辉光 */
    }
    50% {
        border-color: rgba(57, 255, 220, 0.6); /* 边框变亮 */
        box-shadow: 0 0 35px rgba(0, 0, 0, 0.7), 
                    inset 0 0 20px rgba(57, 255, 220, 0.1),
                    0 0 25px rgba(57, 255, 220, 0.4); /* 外部辉光增强 */
    }
    100% {
        border-color: rgba(57, 255, 220, 0.3);
        box-shadow: 0 0 35px rgba(0, 0, 0, 0.7), 
                    inset 0 0 20px rgba(57, 255, 220, 0.1),
                    0 0 15px rgba(57, 255, 220, 0.1); /* 辉光恢复 */
    }
}

/* --- 新对话按钮样式 --- */
#new-chat-button {
    position: absolute;
    top: 15px;
    right: 15px;
    background: transparent;
    border: 1px solid rgba(224, 251, 252, 0.3);
    color: rgba(224, 251, 252, 0.7);
    width: 36px;
    height: 36px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s ease;
}

#new-chat-button:hover {
    background: rgba(57, 255, 220, 0.2);
    color: #e0fbfc;
    border-color: rgba(57, 255, 220, 0.5);
}

/* --- 错误消息的特殊样式 --- */
.error-message {
    color: #ff8a80; /* 醒目的红色字体 */
    border: 1px solid rgba(255, 138, 128, 0.5) !important;
    background-color: rgba(255, 138, 128, 0.1) !important;
}