:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --accent-color: #a855f7;
    --dark-bg: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--dark-bg);
    color: var(--text-primary);
    min-height: 100vh;
}

/* 导航栏样式 */
.navbar {
    background: linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
}

.navbar-brand {
    font-size: 1.3rem;
    font-weight: 600;
}

.navbar-brand i {
    margin-right: 8px;
    color: var(--accent-color);
}

.nav-link {
    color: var(--text-secondary) !important;
    transition: color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary) !important;
}

/* Hero区域 */
.hero {
    padding: 120px 0 80px;
    text-align: center;
    background: linear-gradient(180deg, #1e1b4b 0%, var(--dark-bg) 100%);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 20px;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* 工作流程样式 */
.workflow {
    padding: 80px 0;
    background: linear-gradient(180deg, var(--dark-bg) 0%, #1e1b4b 100%);
}

.workflow-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 20px;
}

.workflow-step {
    flex: 1;
    min-width: 280px;
    max-width: 350px;
    position: relative;
}

.step-circle {
    position: absolute;
    top: -25px;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    z-index: 10;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.step-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 40px 20px 20px;
    text-align: center;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(99, 102, 241, 0.2);
}

.step-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(99, 102, 241, 0.2);
    border-color: var(--primary-color);
}

.step-icon {
    width: 60px;
    height: 60px;
    border-radius: 16px;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.2), rgba(168, 85, 247, 0.2));
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 1.8rem;
    color: var(--accent-color);
}

.step-card h3 {
    font-size: 1.25rem;
    margin-bottom: 10px;
}

.step-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
}

.workflow-arrow {
    font-size: 2rem;
    color: var(--primary-color);
    margin: 0 10px;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.5; }
    50% { opacity: 1; }
}

/* 功能卡片样式 */
.features {
    padding: 80px 0;
}

.feature-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 30px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid rgba(99, 102, 241, 0.1);
    height: 100%;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 25px 50px rgba(99, 102, 241, 0.15);
    border-color: var(--primary-color);
}

.feature-icon {
    width: 50px;
    height: 50px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 20px;
    transition: transform 0.3s ease;
}

.feature-card:hover .feature-icon {
    transform: scale(1.1);
}

.llm-icon {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.2), rgba(99, 102, 241, 0.2));
    color: #60a5fa;
}

.multi-icon {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(34, 197, 94, 0.2));
    color: #4ade80;
}

.video-icon {
    background: linear-gradient(135deg, rgba(249, 115, 22, 0.2), rgba(236, 72, 153, 0.2));
    color: #fb923c;
}

.chat-icon {
    background: linear-gradient(135deg, rgba(168, 85, 247, 0.2), rgba(139, 92, 246, 0.2));
    color: #c084fc;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.875rem;
    line-height: 1.6;
    margin-bottom: 20px;
}

.feature-link {
    display: flex;
    align-items: center;
    color: var(--primary-color);
    font-size: 0.875rem;
    font-weight: 500;
    transition: color 0.3s ease;
}

.feature-link:hover {
    color: var(--accent-color);
}

.feature-link i {
    margin-left: 8px;
    transition: transform 0.3s ease;
}

.feature-card:hover .feature-link i {
    transform: translateX(5px);
}

/* 页脚样式 */
.footer {
    background: #1e1b4b;
    padding: 30px 0;
    margin-top: 50px;
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* 通用按钮样式 */
.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border: none;
    padding: 12px 30px;
    border-radius: 10px;
    font-weight: 600;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(99, 102, 241, 0.4);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .workflow-container {
        flex-direction: column;
    }
    
    .workflow-arrow {
        transform: rotate(90deg);
        margin: 20px 0;
    }
    
    .workflow-step {
        max-width: 100%;
    }
}

/* 内容页面通用样式 */
.content-section {
    padding: 100px 0 50px;
}

.content-card {
    background: var(--card-bg);
    border-radius: 16px;
    padding: 30px;
    border: 1px solid rgba(99, 102, 241, 0.1);
}

.content-card h2 {
    margin-bottom: 20px;
    color: var(--text-primary);
}

.content-card p {
    color: var(--text-secondary);
    line-height: 1.8;
}

.form-control,
.form-select {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    border-radius: 10px;
}

.form-control:focus,
.form-select:focus {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
    color: var(--text-primary);
}

.form-control::placeholder {
    color: var(--text-secondary);
}

/* 代码块样式 */
.code-block {
    background: #0f172a;
    border-radius: 10px;
    padding: 20px;
    overflow-x: auto;
    border: 1px solid rgba(99, 102, 241, 0.2);
}

.code-block pre {
    margin: 0;
    font-family: 'Fira Code', monospace;
    font-size: 0.875rem;
    line-height: 1.6;
    color: var(--text-primary);
}

.copy-btn {
    float: right;
    margin-top: -35px;
    background: rgba(99, 102, 241, 0.2);
    border: none;
    color: var(--text-primary);
    padding: 5px 12px;
    border-radius: 6px;
    font-size: 0.75rem;
    cursor: pointer;
    transition: background 0.3s ease;
}

.copy-btn:hover {
    background: var(--primary-color);
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(99, 102, 241, 0.3);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 聊天消息样式 */
.chat-message {
    margin-bottom: 20px;
}

.chat-message.user .message-content {
    background: var(--primary-color);
    color: white;
    border-radius: 16px 16px 4px 16px;
    padding: 15px 20px;
    display: inline-block;
    max-width: 70%;
}

.chat-message.assistant .message-content {
    background: rgba(99, 102, 241, 0.15);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: 16px 16px 16px 4px;
    padding: 15px 20px;
    display: inline-block;
    max-width: 70%;
    color: var(--text-primary);
}

.chat-container {
    max-height: 500px;
    overflow-y: auto;
    padding-right: 10px;
}

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

.chat-container::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 3px;
}

.chat-container::-webkit-scrollbar-thumb {
    background: rgba(99, 102, 241, 0.3);
    border-radius: 3px;
}

.chat-container::-webkit-scrollbar-thumb:hover {
    background: rgba(99, 102, 241, 0.5);
}