:root {
    --fdfs-accent: #0073aa;
    --fdfs-accent-hover: #005177;
    --fdfs-border: #ddd;
    --fdfs-error: #f44336;
}

.fdfs-donation-form {
    max-width: 600px;
    padding: 30px;
    background: #f9f9f9;
    border-radius: 8px;
}

.fdfs-amount-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 10px;
    margin-bottom: 20px;
}

.fdfs-amount-btn {
    padding: 15px;
    background: #fff;
    border: 2px solid var(--fdfs-border);
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    transition: all 0.3s;
}

.fdfs-amount-btn:hover,
.fdfs-amount-btn.active {
    background: var(--fdfs-accent);
    color: #fff;
    border-color: var(--fdfs-accent);
}

.fdfs-custom-amount,
.fdfs-email,
.fdfs-payment-type,
.fdfs-interval,
.fdfs-note {
    margin-bottom: 20px;
}

.fdfs-custom-amount label,
.fdfs-email label,
.fdfs-interval label,
.fdfs-note label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.fdfs-custom-amount input,
.fdfs-email input,
.fdfs-interval select,
.fdfs-note textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--fdfs-border);
    border-radius: 5px;
    font-size: 16px;
}

.fdfs-note textarea {
    resize: vertical;
}

.fdfs-payment-type label {
    display: block;
    margin-bottom: 10px;
}

.fdfs-submit-btn {
    width: 100%;
    padding: 15px;
    background: var(--fdfs-accent);
    color: #fff;
    border: none;
    border-radius: 5px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s;
}

.fdfs-submit-btn:hover {
    background: var(--fdfs-accent-hover);
}

.fdfs-submit-btn:disabled {
    background: #ccc;
    cursor: not-allowed;
}

.fdfs-success-message {
    padding: 15px;
    background: #4caf50;
    color: #fff;
    border-radius: 5px;
    margin-bottom: 15px;
}

.fdfs-error-message {
    padding: 15px;
    background: var(--fdfs-error);
    color: #fff;
    border-radius: 5px;
    margin-top: 15px;
}