body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #1e1e1e;
    color: #f0f0f0;
    margin: 0;
    padding: 16px;
}
.container {
    max-width: 480px;
    margin: 0 auto;
}
h1 {
    text-align: center;
    margin-bottom: 24px;
}
.account-card {
    background: #2d2d2d;
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}
.account-name {
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 8px;
}
.balance {
    font-size: 24px;
    font-weight: bold;
}
.low {
    color: #ff6b6b;
}
.normal {
    color: #4ecdc4;
}
.user-id, .email {
    font-size: 14px;
    color: #aaa;
    margin-top: 4px;
}
button {
    width: 100%;
    padding: 14px;
    background: #4ecdc4;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    color: #1e1e1e;
    font-weight: bold;
    cursor: pointer;
    margin-top: 16px;
}