@charset "UTF-8";

/**
 * 学生问答系统样式表 - UTF-8支持
 * Student Q&A System Styles with UTF-8 Support
 */

/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 根字体设置 - 确保UTF-8字符正确显示 */
:root {
    /* 颜色变量 */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --psychology-color: #06d6a0;
    
    /* 中性色 */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-card: rgba(255, 255, 255, 0.95);
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --shadow-light: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* 字体设置 - 优化中英文显示 */
    --font-family: 'Segoe UI', 'Microsoft YaHei', '微软雅黑', 'PingFang SC', 'Hiragino Sans GB', 'Source Han Sans CN', 'WenQuanYi Zen Hei', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Source Code Pro', 'Microsoft YaHei Mono', monospace;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* 动画 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* 暗色主题 */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #0f172a;
        --bg-secondary: #1e293b;
        --bg-card: rgba(30, 41, 59, 0.95);
        --text-primary: #f1f5f9;
        --text-secondary: #cbd5e1;
        --text-muted: #64748b;
        --border-color: #334155;
    }
}

/* 基础样式 */
html {
    font-size: 16px;
    line-height: 1.6;
    -webkit-text-size-adjust: 100%;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-family);
    background: var(--primary-gradient);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
    
    /* 确保中文字符正确显示 */
    font-feature-settings: 'kern' 1;
    font-variant-ligatures: common-ligatures;
}

/* 动画背景 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 40% 80%, rgba(120, 199, 255, 0.3) 0%, transparent 50%);
    animation: backgroundFloat 20s ease-in-out infinite;
    z-index: -1;
}

@keyframes backgroundFloat {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

/* 主容器 */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

/* 头部区域 */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg);
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-medium);
    border: 1px solid var(--border-color);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo-icon {
    font-size: 2rem;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.title {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* 语言切换按钮 */
.language-selector {
    position: relative;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    font-family: var(--font-family);
    font-size: 0.875rem;
    color: var(--text-primary);
}

.lang-btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-medium);
    border-color: var(--primary-gradient);
}

.lang-btn:active {
    transform: translateY(0);
}

/* 欢迎区域 */
.welcome-section {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-medium);
    border: 1px solid var(--border-color);
}

.welcome-text {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.7;
}

.feature-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    justify-content: center;
}

.tag {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-normal);
    user-select: none;
}

.tag:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.2) 0%, rgba(118, 75, 162, 0.2) 100%);
}

.tag:active {
    transform: translateY(-1px);
    transition: all 0.1s ease;
}

.tag[data-category="psychology"] {
    background: linear-gradient(135deg, rgba(6, 214, 160, 0.1) 0%, rgba(6, 214, 160, 0.1) 100%);
    border-color: rgba(6, 214, 160, 0.3);
}

.tag[data-category="psychology"]:hover {
    background: linear-gradient(135deg, rgba(6, 214, 160, 0.2) 0%, rgba(6, 214, 160, 0.2) 100%);
}

/* 问答区域 */
.qa-section {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

/* 聊天历史 */
.chat-history {
    flex: 1;
    min-height: 400px;
    max-height: 600px;
    overflow-y: auto;
    padding: var(--spacing-lg);
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-medium);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.chat-history::-webkit-scrollbar {
    width: 6px;
}

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

.chat-history::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.chat-history::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

.chat-message {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message-content {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    line-height: 1.6;
    word-wrap: break-word;
    hyphens: auto;
}

.system-message .message-content {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border: 1px solid rgba(102, 126, 234, 0.2);
}

.user-message .message-content {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.1) 0%, rgba(5, 150, 105, 0.1) 100%);
    border: 1px solid rgba(16, 185, 129, 0.2);
    margin-left: auto;
    max-width: 80%;
}

.assistant-message .message-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    max-width: 90%;
}

.psychology-alert .message-content {
    background: linear-gradient(135deg, rgba(6, 214, 160, 0.1) 0%, rgba(4, 120, 87, 0.1) 100%);
    border: 1px solid rgba(6, 214, 160, 0.3);
}

.system-icon,
.user-icon,
.assistant-icon {
    font-size: 1.2rem;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 32px;
    min-height: 32px;
}

.system-icon img,
.user-icon img,
.assistant-icon img {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}

.message-text {
    flex: 1;
    font-size: 0.95rem;
    line-height: 1.6;
}

.message-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: var(--spacing-sm);
}

/* 思考指示器样式 */
.thinking-indicator {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-secondary);
    font-style: italic;
}

.thinking-dots {
    display: flex;
    align-items: center;
    gap: 2px;
}

.thinking-dots .dot {
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background-color: var(--text-secondary);
    animation: thinkingPulse 1.4s infinite ease-in-out;
}

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

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

.thinking-dots .dot:nth-child(3) {
    animation-delay: 0s;
}

@keyframes thinkingPulse {
    0%, 80%, 100% {
        transform: scale(0.6);
        opacity: 0.5;
    }
    40% {
        transform: scale(1);
        opacity: 1;
    }
}

.thinking-message .message-content {
    opacity: 0.8;
}



/* 输入区域 */
.input-section {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-medium);
    border: 1px solid var(--border-color);
}

.question-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.input-group {
    display: flex;
    gap: var(--spacing-md);
    align-items: stretch;
}

.question-input {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-family: var(--font-family);
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: all var(--transition-normal);
    outline: none;
    line-height: 1.5;
}

.question-input:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
    transform: translateY(-1px);
}

.question-input::placeholder {
    color: var(--text-muted);
}

.submit-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--primary-gradient);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-family: var(--font-family);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    outline: none;
    min-width: 100px;
}

.submit-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-heavy);
}

.submit-btn:active:not(:disabled) {
    transform: translateY(-1px);
}

.submit-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.input-counter {
    text-align: right;
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* 操作按钮区域样式 */
.action-buttons-section {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-light);
    animation: slideUp 0.3s ease;
}

.action-buttons-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
}

.action-buttons-row {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    justify-content: center;
    width: 100%;
}

.action-button {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
    min-height: 44px;
    text-align: center;
    white-space: nowrap;
}

.action-button.ai-handover {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.3);
}

.action-button.ai-handover:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(102, 126, 234, 0.4);
}

.action-button.ai-link {
    background: linear-gradient(135deg, #06d6a0 0%, #10b981 100%);
    color: white;
    box-shadow: 0 2px 8px rgba(16, 185, 129, 0.3);
}

.action-button.ai-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(16, 185, 129, 0.4);
}

.action-button.ai-exit {
    background: linear-gradient(135deg, #6b7280 0%, #4b5563 100%);
    color: white;
    box-shadow: 0 2px 8px rgba(107, 114, 128, 0.3);
    font-size: 0.8rem;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 20px;
}

.action-button.ai-exit:hover {
    transform: translateY(-1px);
    box-shadow: 0 3px 12px rgba(107, 114, 128, 0.4);
}

.action-button-icon {
    font-size: 1rem;
    flex-shrink: 0;
}

.action-button-text {
    font-size: inherit;
}

/* 响应式适配 */
@media (max-width: 768px) {
    .action-buttons-section {
        margin-top: var(--spacing-md);
        padding: var(--spacing-sm);
    }
    
    .action-buttons-row {
        flex-direction: column;
        align-items: center;
        gap: var(--spacing-xs);
    }
    
    .action-button {
        min-width: 240px;
        width: 100%;
        justify-content: center;
    }
    
    .action-button.ai-exit {
        min-width: 160px;
        width: auto;
    }
}

@media (max-width: 480px) {
    .action-buttons-section {
        margin: var(--spacing-sm) calc(-1 * var(--spacing-md));
        border-radius: 0;
        border-left: none;
        border-right: none;
    }
    
    .action-button {
        min-width: 100%;
        font-size: 0.9rem;
        padding: var(--spacing-md);
    }
    
    .action-button.ai-exit {
        min-width: 100%;
        font-size: 0.8rem;
        padding: var(--spacing-sm) var(--spacing-md);
    }
}

/* 状态区域 */
.status-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-light);
    border: 1px solid var(--border-color);
    font-size: 0.875rem;
}

.connection-status {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success-color);
    animation: pulse 2s infinite;
}

.status-dot.error {
    background: var(--error-color);
}

.status-dot.warning {
    background: var(--warning-color);
}

.stats-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

/* 清空聊天按钮 */
.clear-chat-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    font-size: 0.7rem;
    font-weight: 400;
    cursor: pointer;
    transition: all var(--transition-fast);
    outline: none;
    margin-left: var(--spacing-sm);
    opacity: 0.3; /* 初始状态半透明 */
    pointer-events: none; /* 初始状态不可点击 */
}

.clear-chat-btn.active {
    opacity: 1;
    pointer-events: auto;
}

.clear-chat-btn:hover {
    background: rgba(239, 68, 68, 0.1);
    border-color: rgba(239, 68, 68, 0.3);
    color: var(--error-color);
}

.clear-chat-btn:active {
    transform: scale(0.95);
    transition: all 0.1s ease;
}

.clear-icon {
    font-size: 0.8rem;
}

.clear-text {
    font-size: 0.7rem;
}

/* 加载指示器 */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    backdrop-filter: blur(4px);
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    text-align: center;
    color: white;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-text {
    font-size: 1rem;
    font-weight: 500;
}

/* 错误提示 */
.error-toast {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    background: white;
    border: 1px solid var(--error-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-heavy);
    z-index: 10000;
    transform: translateX(400px);
    transition: transform var(--transition-normal);
    max-width: 400px;
}

.error-toast.active {
    transform: translateX(0);
}

.toast-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
}

.toast-icon {
    font-size: 1.2rem;
    color: var(--error-color);
    flex-shrink: 0;
}

.toast-message {
    flex: 1;
    font-size: 0.875rem;
    color: var(--text-primary);
    line-height: 1.5;
}

.toast-close {
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.toast-close:hover {
    background: var(--border-color);
    color: var(--text-primary);
}

/* AI接管相关样式 */
.ai-handover-section {
    margin-top: var(--spacing-md);
    padding: 0;
    background: none;
    border: none;
}

.handover-prompt {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-sm);
    text-align: left;
}

.ai-handover-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.3);
}

.ai-handover-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(102, 126, 234, 0.4);
}

.ai-handover-btn:active {
    transform: translateY(0);
    transition: all 0.1s ease;
}

.ai-icon {
    font-size: 1rem;
}

.ai-text {
    font-size: 0.875rem;
}

/* AI模式指示器 */
.ai-mode-indicator {
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-lg);
    margin-top: var(--spacing-md);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
    animation: slideInFromTop 0.3s ease;
}

@keyframes slideInFromTop {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.ai-mode-text {
    font-size: 0.875rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}



/* AI生成的消息样式 */
.assistant-message[data-ai="true"] .message-content {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border-left: 4px solid #667eea;
}

.assistant-message[data-ai="true"] .assistant-icon {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 50%;
    padding: 4px;
    font-size: 0.8rem;
}

/* AI回复操作按钮样式 - 简洁版 */
.ai-actions-section {
    margin-top: var(--spacing-lg);
    padding: 0;
    background: none;
    border: none;
    box-shadow: none;
}

.ai-actions-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

/* 链接按钮行 */
.ai-links-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--spacing-sm);
    width: 100%;
}

/* 退出按钮行 */
.ai-exit-row {
    display: flex;
    justify-content: center;
    margin-top: var(--spacing-sm);
}

.ai-link-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 12px var(--spacing-md);
    background: linear-gradient(135deg, #06d6a0 0%, #10b981 100%);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
    box-shadow: var(--shadow-light);
    min-height: 44px;
    text-align: center;
}

.ai-link-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.3);
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

.ai-link-btn:active {
    transform: translateY(0);
    box-shadow: var(--shadow-light);
}

.ai-link-btn .link-icon {
    font-size: 1rem;
    flex-shrink: 0;
}

.ai-link-btn .link-text {
    font-size: 0.875rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.exit-ai-small-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 8px var(--spacing-lg);
    background: linear-gradient(135deg, #6b7280 0%, #4b5563 100%);
    color: white;
    border: none;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-light);
    opacity: 0.8;
}

.exit-ai-small-btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-medium);
    background: linear-gradient(135deg, #4b5563 0%, #374151 100%);
    opacity: 1;
}

.exit-ai-small-btn:active {
    transform: translateY(0);
}

.exit-ai-small-btn .exit-icon {
    font-size: 0.8rem;
}

.exit-ai-small-btn .exit-text {
    font-size: 0.8rem;
}

/* 响应式优化 */
@media (max-width: 768px) {
    .ai-links-row {
        grid-template-columns: 1fr;
        gap: var(--spacing-xs);
    }
    
    .ai-link-btn {
        padding: 14px var(--spacing-md);
        font-size: 0.9rem;
    }
    
    .ai-actions-section {
        margin-top: var(--spacing-md);
        padding: 0;
    }
}

@media (max-width: 480px) {
    .ai-link-btn .link-text {
        font-size: 0.8rem;
    }
    
    .exit-ai-small-btn {
        padding: 6px var(--spacing-md);
        font-size: 0.75rem;
    }
}

/* 模态框 */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    backdrop-filter: blur(4px);
}

.modal-overlay.active {
    display: flex;
}

.modal {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-heavy);
    max-width: 500px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    border: 1px solid var(--border-color);
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50px) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background: var(--border-color);
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-lg);
    text-align: center;
}

.support-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-lg);
}

.modal-body p {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

.support-contacts {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.contact-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    font-size: 0.875rem;
}

.contact-item:not(:last-child) {
    border-bottom: 1px solid var(--border-color);
}

.contact-item a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition-fast);
}

.contact-item a:hover {
    color: #764ba2;
    text-decoration: underline;
}

.modal-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
}

.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-family: var(--font-family);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    outline: none;
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-medium);
}



/* 页脚 */
.footer {
    text-align: center;
    padding: var(--spacing-lg);
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.75rem;
    line-height: 1.6;
}

.tech-info {
    margin-top: var(--spacing-sm);
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-md);
        gap: var(--spacing-md);
    }
    
    .header {
        flex-direction: column;
        gap: var(--spacing-md);
        text-align: center;
    }
    
    .title {
        font-size: 1.25rem;
    }
    
    .welcome-text {
        font-size: 1rem;
    }
    
    .feature-tags {
        justify-content: center;
    }
    
    .tag {
        font-size: 0.8rem;
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .input-group {
        flex-direction: column;
    }
    
    .submit-btn {
        justify-content: center;
    }
    
    .status-section {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
    
    .stats-info {
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .clear-chat-btn {
        margin-left: 0;
        margin-top: var(--spacing-xs);
        font-size: 0.65rem;
    }
    
    .clear-text {
        display: none;
    }
    
    .user-message .message-content {
        max-width: 95%;
        margin-left: 5%;
    }
    
    .assistant-message .message-content {
        max-width: 95%;
    }
    
    .error-toast {
        top: var(--spacing-sm);
        right: var(--spacing-sm);
        left: var(--spacing-sm);
        max-width: none;
    }
    
    .modal {
        width: 95%;
        margin: var(--spacing-sm);
    }
    

}

@media (max-width: 480px) {
    .container {
        padding: var(--spacing-sm);
    }
    
    .header,
    .welcome-section,
    .chat-history,
    .input-section {
        padding: var(--spacing-md);
    }
    
    .title {
        font-size: 1.125rem;
    }
    
    .chat-history {
        min-height: 300px;
        max-height: 400px;
    }
    
    .question-input {
        font-size: 16px; /* 防止iOS缩放 */
    }
}

/* 打印样式 */
@media print {
    body {
        background: white;
        color: black;
    }
    
    .header,
    .input-section,
    .status-section,
    .loading-overlay,
    .error-toast,
    .modal-overlay {
        display: none;
    }
    
    .chat-history {
        box-shadow: none;
        border: 1px solid #ccc;
        max-height: none;
        overflow: visible;
    }
}

/* 高对比度模式 */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000;
        --text-secondary: #000;
        --text-muted: #333;
    }
    
    .tag,
    .message-content {
        border: 2px solid #000;
    }
}

/* 减少动画 */
@media (prefers-reduced-motion: reduce) {
    *,
    ::before,
    ::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* 学生ID输入组件样式 */
.student-id-group {
    margin-bottom: var(--spacing-lg);
    background: var(--bg-card);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-light);
}

.student-id-label {
    display: block;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-size: 0.9rem;
}

.student-id-label .required {
    color: var(--error-color);
    margin-left: var(--spacing-xs);
}

.student-id-input-wrapper {
    display: flex;
    align-items: center;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.student-id-input-wrapper:focus-within {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
    transform: translateY(-1px);
}

.student-id-prefix {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    font-weight: 700;
    font-size: 1rem;
    border-radius: var(--radius-sm);
    margin-right: var(--spacing-sm);
    min-width: 32px;
    text-align: center;
    box-shadow: var(--shadow-light);
}

.student-id-input {
    flex: 1;
    border: none;
    outline: none;
    background: transparent;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    font-family: var(--font-mono);
    letter-spacing: 2px;
    padding: var(--spacing-sm);
}

.student-id-input::placeholder {
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 1px;
}

.student-id-hint {
    margin-top: var(--spacing-sm);
    font-size: 0.8rem;
    color: var(--text-muted);
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.student-id-hint::before {
    content: 'ℹ️';
    font-size: 0.9rem;
}

.student-id-hint.warning {
    color: var(--warning-color);
}

.student-id-hint.warning::before {
    content: '⚠️';
}

.student-id-hint.success {
    color: var(--success-color);
    font-weight: 500;
}

.student-id-hint.success::before {
    content: '✅';
}

/* 学生ID输入框响应式设计 */
@media (max-width: 768px) {
    .student-id-group {
        padding: var(--spacing-md);
        margin-bottom: var(--spacing-md);
    }
    
    .student-id-input-wrapper {
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .student-id-prefix {
        font-size: 0.9rem;
        padding: var(--spacing-xs) var(--spacing-sm);
        min-width: 28px;
    }
    
    .student-id-input {
        font-size: 0.9rem;
        letter-spacing: 1px;
    }
}

/* 学生ID输入框动画效果 */
.student-id-input-wrapper {
    position: relative;
}

.student-id-input-wrapper::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transition: width var(--transition-normal);
}

.student-id-input-wrapper:focus-within::after {
    width: 100%;
}

/* 错误状态样式 */
.student-id-input-wrapper.error {
    border-color: var(--error-color);
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.student-id-input-wrapper.error::after {
    background: var(--error-color);
}

/* 成功状态样式 */
.student-id-input-wrapper.success {
    border-color: var(--success-color);
}

.student-id-input-wrapper.success::after {
    background: var(--success-color);
    width: 100%;
}

/* 学生ID对话框样式 */
.student-id-modal {
    z-index: 20000;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
}

.student-id-modal.active {
    display: flex;
}

.student-id-dialog {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    max-width: 500px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-heavy);
    border: 1px solid var(--border-color);
    position: relative;
    animation: dialogSlideIn 0.4s ease-out;
}

@keyframes dialogSlideIn {
    from {
        transform: translateY(-50px) scale(0.95);
        opacity: 0;
    }
    to {
        transform: translateY(0) scale(1);
        opacity: 1;
    }
}

.dialog-header {
    text-align: center;
    padding: var(--spacing-xl) var(--spacing-lg) var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.dialog-avatar {
    margin-bottom: var(--spacing-md);
}

.avatar-img {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.9);
    padding: var(--spacing-sm);
}

.dialog-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.dialog-header p {
    font-size: 0.9rem;
    opacity: 0.9;
    margin: 0;
}

.dialog-body {
    padding: var(--spacing-xl);
}

.dialog-step {
    animation: stepFadeIn 0.3s ease-out;
}

@keyframes stepFadeIn {
    from {
        opacity: 0;
        transform: translateX(20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.bot-message {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.bot-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.message-bubble {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    flex: 1;
    box-shadow: var(--shadow-light);
}

.message-bubble p {
    margin: 0 0 var(--spacing-sm) 0;
    line-height: 1.5;
}

.message-bubble p:last-child {
    margin-bottom: 0;
}

.user-input-area {
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-lg);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-light);
}

.input-label {
    display: block;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-size: 0.9rem;
}

.input-label .required {
    color: var(--error-color);
    margin-left: var(--spacing-xs);
}

.dialog-student-id-wrapper {
    display: flex;
    align-items: center;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.dialog-student-id-wrapper:focus-within {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
    transform: translateY(-1px);
}

.dialog-prefix {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    font-weight: 700;
    font-size: 1rem;
    border-radius: var(--radius-sm);
    margin-right: var(--spacing-sm);
    min-width: 32px;
    text-align: center;
    box-shadow: var(--shadow-light);
}

.dialog-student-id-input {
    flex: 1;
    border: none;
    outline: none;
    background: transparent;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    font-family: var(--font-mono);
    letter-spacing: 2px;
    padding: var(--spacing-sm);
}

.dialog-student-id-input::placeholder {
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 1px;
}

.dialog-hint {
    margin-top: var(--spacing-sm);
    font-size: 0.8rem;
    color: var(--text-muted);
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.dialog-hint::before {
    content: 'ℹ️';
    font-size: 0.9rem;
}

.dialog-hint.warning {
    color: var(--warning-color);
}

.dialog-hint.warning::before {
    content: '⚠️';
}

.dialog-hint.success {
    color: var(--success-color);
    font-weight: 500;
}

.dialog-hint.success::before {
    content: '✅';
}

.dialog-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    margin-top: var(--spacing-xl);
    flex-wrap: wrap;
}

.dialog-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
    min-width: 120px;
    justify-content: center;
}

.dialog-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.dialog-btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: var(--shadow-light);
}

.dialog-btn.primary:not(:disabled):hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.dialog-btn.secondary {
    background: var(--bg-card);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.dialog-btn.secondary:not(:disabled):hover {
    background: var(--bg-primary);
    transform: translateY(-1px);
}

/* 学生信息条样式 */
.student-info-bar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-light);
}

.student-info-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    color: white;
}

.student-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.student-details {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.student-label {
    font-size: 0.8rem;
    opacity: 0.9;
}

.student-id-display {
    font-size: 1.1rem;
    font-weight: 700;
    font-family: var(--font-mono);
    letter-spacing: 1px;
}

.change-id-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    border-radius: var(--radius-sm);
    padding: var(--spacing-sm);
    color: white;
    cursor: pointer;
    transition: all var(--transition-normal);
    font-size: 0.9rem;
}

.change-id-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .student-id-dialog {
        margin: var(--spacing-md);
        width: calc(100% - 2rem);
    }
    
    .dialog-actions {
        flex-direction: column;
    }
    
    .dialog-btn {
        min-width: auto;
        width: 100%;
    }
    
    .student-info-content {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-sm);
    }
    
    .student-details {
        align-items: center;
    }
}

/* ===== Telegram-style Link Buttons ===== */
.message-links {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid rgba(0, 0, 0, 0.05);
}

.message-link-button {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 14px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px rgba(102, 126, 234, 0.2);
}

.message-link-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.3);
    background: linear-gradient(135deg, #5568d3 0%, #6a3f8f 100%);
}

.message-link-button:active {
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(102, 126, 234, 0.2);
}

.message-link-button .link-icon {
    font-size: 16px;
    flex-shrink: 0;
}

.message-link-button .link-text {
    flex: 1;
    text-align: left;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.message-link-button .link-arrow {
    font-size: 16px;
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.message-link-button:hover .link-arrow {
    transform: translateX(3px);
}

/* Dark mode support for link buttons */
@media (prefers-color-scheme: dark) {
    .message-links {
        border-top-color: rgba(255, 255, 255, 0.1);
    }
    
    .message-link-button {
        background: linear-gradient(135deg, #5568d3 0%, #6a3f8f 100%);
    }
    
    .message-link-button:hover {
        background: linear-gradient(135deg, #4a5cc2 0%, #5d367e 100%);
    }
}

/* Responsive link buttons */
@media (max-width: 768px) {
    .message-link-button {
        font-size: 13px;
        padding: 9px 12px;
    }
    
    .message-link-button .link-icon,
    .message-link-button .link-arrow {
        font-size: 14px;
    }
}