body {
    margin: 0;
    padding: 0;
    min-height: 100vh;
    background: #fff;
    color: #18181b;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, Helvetica, sans-serif;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

h1 {
    font-size: 2.7rem;
    font-weight: 600;
    letter-spacing: -1px;
    margin-bottom: 2.5rem;
    color: #18181b;
    background: none;
    text-align: center;
    line-height: 1.1;
}

button {
    background: #f5f5f7;
    color: #18181b;
    border: 1px solid #e5e5ea;
    border-radius: 0.8rem;
    padding: 0.9rem 2.5rem;
    font-size: 1.08rem;
    font-weight: 500;
    margin: 0.5rem;
    cursor: pointer;
    transition: 
        background 0.18s, 
        color 0.18s, 
        border 0.18s, 
        box-shadow 0.18s,
        transform 0.12s;
    box-shadow: 0 2px 12px 0 rgba(60,60,67,0.04);
    outline: none;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

button:hover, button:focus {
    background: #4caf50; /* green background */
    color: #fff;
    border: 1px solid #4caf50;
    box-shadow: 0 4px 24px 0 rgba(60,60,67,0.10);
    transform: translateY(-2px) scale(1.05);
}

button:active {
    background: #4caf50;
    color: #fff;
    border: 1px solid #4caf50;
    box-shadow: 0 4px 24px 0 rgba(60,60,67,0.10);
    transform: translateY(-2px) scale(1.05);
}

@media (max-width: 600px) {
    h1 {
        font-size: 1.6rem;
    }
    button {
        width: 90vw;
        max-width: 320px;
        font-size: 1rem;
        padding: 0.8rem 0;
    }
    body {
        padding: 2rem 0;
    }
}