body {
    font-family: 'Arial Narrow', 'Helvetica Neue', Helvetica, Arial, sans-serif; /* Tall, condensed sans-serif stack */
    background-color: #000000; /* Black background */
    color: #ffffff; /* White text for contrast */
    display: flex;
    flex-direction: column; /* Align items vertically */
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    box-sizing: border-box;
    text-align: center; /* Center text globally */
}

.main-content {
    /* Removed card styling (background, padding, shadow, border-radius) */
    max-width: 500px; /* Max width for the content area */
    width: 100%;
}

h1 {
    color: #E0E0E0; /* Light grey for the main title, can be #FFFFFF too */
    font-size: 2.8em; /* Larger font size for the title */
    font-weight: bold; /* Ensure title is bold */
    margin-bottom: 30px; /* Space below the title */
    text-transform: uppercase; /* Uppercase title */
    letter-spacing: 2px; /* Add some letter spacing */
}

.form-group {
    margin-bottom: 25px; /* Increased space for better readability */
    text-align: left; /* Align label and input to the left within the group */
}

label {
    display: block;
    margin-bottom: 10px; /* Space between label and input */
    font-weight: normal; /* Normal font weight for label */
    color: #CCCCCC; /* Lighter grey for label */
    font-size: 1.1em;
}

input[type="email"] {
    width: 100%; /* Full width relative to its container */
    padding: 12px 15px; /* Increased padding */
    border: 1px solid #555555; /* Darker border */
    border-radius: 4px;
    font-size: 16px;
    background-color: #1a1a1a; /* Dark input background */
    color: #E0E0E0; /* Light text in input */
    box-sizing: border-box; /* Ensure padding doesn't expand width */
}

input[type="email"]:focus {
    border-color: #CCCCCC; /* Light grey border on focus */
    outline: none;
    box-shadow: 0 0 8px rgba(204, 204, 204, 0.3); /* Subtle light grey glow on focus */
}

button[type="submit"] {
    background-color: #333333; /* Dark grey button */
    color: white;
    border: none;
    padding: 12px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    font-weight: bold;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.1s ease;
    width: 100%; /* Full width button */
    margin-top: 10px; /* Space above the button */
}

button[type="submit"]:hover {
    background-color: #555555; /* Slightly lighter grey on hover */
}

button[type="submit"]:active {
    transform: scale(0.98); /* Slight press effect */
}

button[type="submit"]:disabled {
    background-color: #555555; /* Dark grey for disabled state */
    color: #888888;
    cursor: not-allowed;
}

#responseMessage {
    margin-top: 25px; /* Increased space for response message */
    font-size: 1em;
    min-height: 1.5em;
    font-weight: bold;
}

#responseMessage.success {
    color: #28a745; /* Green for success */
}

#responseMessage.error {
    color: #dc3545; /* Red for error */
}