body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
}

.container {
    max-width: 500px;
    margin: 50px auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

h1, h2 {
    text-align: center;
    color: #333;
}

.input-container {
    display: flex;
    flex-direction: column;
    margin-bottom: 20px;
}

input[type="text"], input[type="password"] {
    width: 100%;
    padding: 10px;
    margin-bottom: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    box-sizing: border-box;
}

#login-btn, #set-goal-btn, #submit-btn {
    background-color: #007bff;
    color: #fff;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

#login-btn:hover, #set-goal-btn:hover, #submit-btn:hover {
    background-color: #0069d9;
}

.goal-container, .activity-container {
    display: none;
}

/* Add more styles as needed */