body {
    font-family: system-ui, sans-serif;
    max-width: 560px;
    margin: 48px auto;
    padding: 20px;
    color: #1a1a1a;
}

h1 {
    margin-bottom: 4px;
}

.intro {
    color: #555;
    margin-top: 4px;
    margin-bottom: 28px;
    line-height: 1.5;
}

form {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

label {
    display: flex;
    flex-direction: column;
    gap: 4px;
    font-weight: 500;
    font-size: 15px;
}

.field-hint {
    font-weight: 400;
    font-size: 13px;
    color: #666;
}

input,
select {
    padding: 10px 12px;
    font-size: 16px;
    border: 1px solid #ccc;
    border-radius: 6px;
    background: #fff;
}

input:focus,
select:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37,99,235,0.15);
}

.key-field {
    display: flex;
    align-items: center;
    gap: 12px;
}

.key-field input[type="number"] {
    width: 80px;
    text-align: center;
}

.key-label {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.key-label strong {
    font-size: 15px;
}

.key-label span {
    font-size: 13px;
    color: #666;
}

button[type="submit"] {
    padding: 12px;
    font-size: 16px;
    font-weight: 600;
    background: #2563eb;
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.15s;
    margin-top: 4px;
}

button[type="submit"]:hover:not(:disabled) {
    background: #1d4ed8;
}

button[type="submit"]:disabled {
    background: #93afd4;
    cursor: not-allowed;
}

.alert {
    padding: 14px 16px;
    border-radius: 8px;
    font-size: 15px;
    line-height: 1.5;
    margin-top: 8px;
}

.alert--error {
    background: #fef2f2;
    border: 1px solid #fca5a5;
    color: #b91c1c;
}

.alert--success {
    background: #f0fdf4;
    border: 1px solid #86efac;
    color: #166534;
}

.success-card {
    background: #f0fdf4;
    border: 1px solid #86efac;
    border-radius: 10px;
    padding: 28px 24px;
    text-align: center;
    color: #166534;
}

.success-card h2 {
    margin: 0 0 10px;
    font-size: 22px;
}

.success-card p {
    margin: 0;
    font-size: 15px;
    line-height: 1.6;
    color: #166534;
}

.resident-meta {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    padding: 14px 16px;
    margin-bottom: 20px;
    font-size: 15px;
    line-height: 1.7;
}