body {
    font-family: Arial, sans-serif;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #74ebd5 0%, #9face6 100%);
    margin: 0;
}

.container {
    background: #fff;
    padding: 25px;
    border-radius: 16px;
    box-shadow: 0px 6px 18px rgba(0, 0, 0, 0.2);
    width: 350px;
    text-align: center;
    animation: fadeIn 0.5s ease;
}

h3 {
    margin-bottom: 15px;
    color: #333;
}

input,
textarea {
    width: 90%;
    margin-top: 12px;
    padding: 12px;
    border: 1px solid #ccc;
    border-radius: 10px;
    font-size: 14px;
    outline: none;
    transition: border 0.3s;
}

input:focus,
textarea:focus {
    border: 1px solid #007BFF;
}

button {
    width: 100%;
    margin-top: 15px;
    padding: 12px;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    background: #007BFF;
    color: white;
    cursor: pointer;
    transition: background 0.3s, transform 0.2s;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
}

button:hover {
    background: #0056b3;
    transform: scale(1.03);
}

/* Spinner inside button */
.spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid #fff;
    border-radius: 50%;
    width: 16px;
    height: 16px;
    animation: spin 1s linear infinite;
    display: none;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

/* Popup */
.popup {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.8);
    background: white;
    padding: 20px 30px;
    border-radius: 12px;
    box-shadow: 0px 6px 18px rgba(0, 0, 0, 0.2);
    text-align: center;
    display: none;
    animation: popupShow 0.3s ease forwards;
    font-size: 15px;
    font-weight: bold;
}

@keyframes popupShow {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.8);
    }

    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

.popup.success {
    border-left: 6px solid #28a745;
    color: #28a745;
}

.popup.error {
    border-left: 6px solid #dc3545;
    color: #dc3545;
}

/* Footer copyright */
.footer {
    margin-top: 20px;
    font-size: 13px;
    color: #fff;
    text-align: center;
}

@media only screen and (max-width: 500px) {
    .container {
        background: #fff;
        padding: 25px;
        border-radius: 16px;
        box-shadow: 0px 6px 18px rgba(0, 0, 0, 0.2);
        width: 80%;
        text-align: center;
        animation: fadeIn 0.5s ease;
    }
}