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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2rem;
    color: #1a1a2e;
}

.subtitle {
    color: #666;
    font-size: 0.95rem;
    margin-top: 0.25rem;
}

.form-section, .table-section {
    background: #fff;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

h2 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: #1a1a2e;
}

.form-group {
    margin-bottom: 1rem;
}

label {
    display: block;
    margin-bottom: 0.4rem;
    font-weight: 500;
    font-size: 0.9rem;
}

input[type="email"] {
    width: 100%;
    padding: 0.6rem 0.8rem;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.2s;
}

input[type="email"]:focus {
    outline: none;
    border-color: #4a6cf7;
    box-shadow: 0 0 0 3px rgba(74, 108, 247, 0.1);
}

button[type="submit"] {
    background: #4a6cf7;
    color: #fff;
    border: none;
    padding: 0.6rem 1.5rem;
    border-radius: 6px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: background 0.2s;
}

button[type="submit"]:hover {
    background: #3a5ce5;
}

button[type="submit"]:disabled {
    background: #a0b0e8;
    cursor: not-allowed;
}

.btn-secondary {
    background: #eee;
    color: #333;
    border: none;
    padding: 0.4rem 1rem;
    border-radius: 6px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-secondary:hover {
    background: #ddd;
}

.btn-danger {
    background: none;
    color: #e74c3c;
    border: 1px solid #e74c3c;
    padding: 0.3rem 0.7rem;
    border-radius: 4px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-danger:hover {
    background: #e74c3c;
    color: #fff;
}

.message {
    margin-top: 0.75rem;
    padding: 0.6rem 0.8rem;
    border-radius: 6px;
    font-size: 0.9rem;
}

.message.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.hidden {
    display: none;
}

.table-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.table-header h2 {
    margin-bottom: 0;
}

table {
    width: 100%;
    border-collapse: collapse;
}

thead th {
    text-align: left;
    padding: 0.6rem 0.8rem;
    border-bottom: 2px solid #eee;
    font-size: 0.85rem;
    color: #666;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

tbody td {
    padding: 0.7rem 0.8rem;
    border-bottom: 1px solid #f0f0f0;
    font-size: 0.9rem;
}

tbody tr:hover {
    background: #f8f9ff;
}

.account-number {
    font-family: "Courier New", monospace;
    font-weight: 600;
    color: #4a6cf7;
}

.loading {
    text-align: center;
    padding: 1rem;
    color: #888;
}

.empty-msg {
    text-align: center;
    color: #999;
    padding: 2rem 0;
}

footer {
    text-align: center;
    color: #999;
    font-size: 0.8rem;
    margin-top: 1rem;
}