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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    color: #ffffff;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    text-align: center;
    max-width: 520px;
    padding: 40px 20px;
}

h1 {
    font-size: 3rem;
    margin-bottom: 10px;
}

.tagline {
    font-size: 1.1rem;
    opacity: 0.9;
}

.subtitle {
    margin: 30px 0;
    font-size: 1rem;
    opacity: 0.85;
}

form {
    margin-top: 20px;
}

input[type="email"] {
    width: 100%;
    padding: 14px;
    border-radius: 6px;
    border: none;
    margin-bottom: 12px;
    font-size: 1rem;
}

button {
    width: 100%;
    padding: 14px;
    background: #00e0ff;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
}

button:hover {
    background: #00bcd4;
}

#response {
    margin-top: 12px;
    font-size: 0.9rem;
}

footer {
    margin-top: 40px;
    font-size: 0.8rem;
    opacity: 0.6;
}