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

        body {
            padding: 20px;
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        }

        /* 动画背景粒子 */
        .particle {
            position: absolute;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.1);
            animation: float 15s infinite ease-in-out;
        }

        @keyframes float {
            0%, 100% {
                transform: translateY(0) translateX(0) rotate(0deg);
            }
            33% {
                transform: translateY(-100px) translateX(100px) rotate(120deg);
            }
            66% {
                transform: translateY(-50px) translateX(-100px) rotate(240deg);
            }
        }

        .container {
            max-width: 1200px;
            width: 100%;
            position: relative;
            z-index: 1;
            margin: 0 auto;
        }

        .header {
            text-align: center;
            margin-bottom: 60px;
            animation: fadeInDown 0.8s ease-out;
        }

        @keyframes fadeInDown {
            from {
                opacity: 0;
                transform: translateY(-30px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }


        
        .btn {
            display: inline-block;
            padding: 15px 40px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            text-decoration: none;
            border-radius: 50px;
            font-weight: 600;
            font-size: 1.1em;
            transition: all 0.3s ease;
            box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
            position: relative;
            overflow: hidden;
            border: none;
            cursor: pointer;
        }

        .btn::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
            transition: left 0.5s ease;
        }

        .btn:hover::before {
            left: 100%;
        }

        .btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 15px 40px rgba(102, 126, 234, 0.6);
        }

        .btn:active {
            transform: translateY(-1px);
        }