```css
body {
    margin: 0;
    min-height: 100vh;
    background: linear-gradient(
        135deg,
        #f4f1ea,
        #e8e0d0
    );
    font-family: Arial, sans-serif;
}

.login-page {
    min-height: 100vh;

    display: flex;
    justify-content: center;
    align-items: center;

    padding: 20px;
}

.login-card {
    width: 100%;
    max-width: 430px;

    background: white;

    padding: 40px;

    border-radius: 18px;

    box-shadow:
        0 10px 30px rgba(0, 0, 0, 0.12);
}

.admin-icon {
    font-size: 55px;
    margin-bottom: 10px;
}

.login-card h2 {
    font-weight: 700;
    color: #333;
}

.login-card .form-control {
    height: 48px;
}

.login-card .btn {
    height: 48px;
    font-weight: 600;
}

.login-card a {
    text-decoration: none;
}

.login-card a:hover {
    text-decoration: underline;
}
```