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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    text-align: center;
    background: rgba(255, 255, 255, 0.95);
    padding: 60px 40px;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    max-width: 600px;
    width: 100%;
    animation: fadeIn 1s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hello-text {
    font-size: 4rem;
    color: #667eea;
    margin-bottom: 20px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
    animation: pulse 2s ease-in-out infinite;
}

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

.subtitle {
    font-size: 1.5rem;
    color: #666;
    margin-bottom: 40px;
    font-weight: 300;
}

.btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 1.1rem;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    font-weight: 600;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

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

.message {
    margin-top: 30px;
    font-size: 1.2rem;
    color: #764ba2;
    font-weight: 500;
    min-height: 30px;
    transition: opacity 0.3s ease;
}

.message.show {
    opacity: 1;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hello-text {
        font-size: 3rem;
    }
    
    .subtitle {
        font-size: 1.2rem;
    }
    
    .container {
        padding: 40px 30px;
    }
}

@media (max-width: 480px) {
    .hello-text {
        font-size: 2.5rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .btn {
        padding: 12px 30px;
        font-size: 1rem;
    }
}