body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #e9ecef;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
}
.login-container {
    background-color: #ffffff;
    padding: 35px 40px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 380px;
    text-align: center;
}
h3 {
    color: #343a40;
    margin-bottom: 25px;
    font-size: 1.2em;
    font-weight: 500;
}
.form-group {
    margin-bottom: 20px;
    text-align: left;
}
label {
    display: block;
    margin-bottom: 8px;
    color: #495057;
    font-size: 0.95em;
    font-weight: 500;
}
input[type="text"],
input[type="password"] {
    width: calc(100% - 0px);
    padding: 12px;
    border: 1px solid #ced4da;
    border-radius: 6px;
    font-size: 1em;
    transition: border-color 0.2s;
    box-sizing: border-box;
}
input[type="text"]:focus,
input[type="password"]:focus {
    border-color: #007bff;
    outline: none;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}
.error-message {
    color: #dc3545;
    background-color: #f8d7da;
    border: 1px solid #f5c6cb;
    padding: 10px 15px;
    border-radius: 6px;
    margin-bottom: 20px;
    font-size: 0.9em;
    text-align: left;
}
button[type="submit"] {
    width: 100%;
    padding: 12px;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 1.1em;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-top: 10px;
}
button[type="submit"]:hover {
    background-color: #0056b3;
}
.btn-secondary {
    display: block;
    width: 100%;
    padding: 10px;
    background-color: #6c757d;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 1em;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-top: 15px;
    box-sizing: border-box;
}
.btn-secondary:hover {
    background-color: #5a6268;
}
.logo {
    height: 60px;
    width: auto;
    margin-right: 15px;
}