:root {
            --primary-color: #007bff;
            --primary-hover-color: #0056b3;
            --success-color: #28a745;
            --success-bg-color: #d4edda;
            --success-border-color: #c3e6cb;
            --error-color: #dc3545;
            --error-bg-color: #f8d7da;
            --error-border-color: #f5c6cb;
            --light-gray-color: #f8f9fa;
            --medium-gray-color: #ced4da;
            --dark-gray-color: #495057;
            --text-color: #333;
            --body-bg-color: #eef2f7; /* Light background for the page */
            --container-bg-color: #ffffff;
            --input-border-color: #ced4da;
            --input-focus-border-color: var(--primary-color);
            --input-focus-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
        }

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

        body {
            font-family: 'Poppins', sans-serif;
            background-color: var(--body-bg-color);
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh; /* Use 100vh for full viewport height */
            padding: 20px; /* Add padding for smaller screens */
        }

        /* Container Styling */
        .login-container {
            background-color: var(--container-bg-color);
            padding: 35px 45px; /* Slightly adjusted padding */
            border-radius: 12px; /* Softer corners */
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
            width: 100%; /* Responsive width */
            max-width: 420px; /* Slightly wider max width */
            text-align: center;
            overflow: hidden; /* Hide overflow for potential animations */
        }

        .login-container h2 {
            margin-bottom: 25px;
            color: var(--primary-color);
            font-weight: 600;
            font-size: 1.8em; /* Larger heading */
        }

        /* Form Styling */
        form {
            width: 100%;
            transition: opacity 0.3s ease-in-out; /* For potential toggle effects */
        }

        .form-group {
            margin-bottom: 20px;
            text-align: left;
            position: relative; /* For potential icon positioning */
        }

        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 500;
            color: var(--dark-gray-color);
            font-size: 0.95em;
        }

        .form-group input {
            width: 100%;
            padding: 12px 15px; /* More padding */
            border: 1px solid var(--input-border-color);
            border-radius: 8px; /* Softer corners for inputs */
            font-size: 1em;
            font-family: 'Poppins', sans-serif;
            color: var(--text-color);
            transition: border-color 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
        }
        /* Add focus effect */
        .form-group input:focus {
            outline: none;
            border-color: var(--input-focus-border-color);
            box-shadow: var(--input-focus-shadow);
        }
        /* Style placeholders */
        .form-group input::placeholder {
            color: var(--medium-gray-color);
            opacity: 0.8;
        }

        /* Button Styling (replaces button-base definition) */
        .button-base {
            width: 100%;
            padding: 12px 15px;
            margin-top: 15px; /* Space above button */
            font-size: 1.05em;
            font-weight: 500;
            color: #fff;
            background-color: var(--primary-color);
            border: none;
            border-radius: 8px;
            cursor: pointer;
            transition: background-color 0.2s ease-in-out, transform 0.1s ease;
            text-transform: uppercase; /* Optional: Uppercase text */
            letter-spacing: 0.5px; /* Optional: Letter spacing */
        }
        .button-base:hover {
            background-color: var(--primary-hover-color);
        }
        .button-base:active {
            transform: scale(0.98); /* Slight press effect */
        }

        /* Message Styling */
        .message {
            margin-top: 20px;
            padding: 12px 15px;
            border-radius: 8px;
            font-weight: 500;
            font-size: 0.95em;
            border: 1px solid transparent;
            display: none; /* Keep hidden initially */
            text-align: left; /* Align message text left */
            position: relative; /* For icon positioning */
            padding-left: 40px; /* Space for icon */
        }
        /* Add icons using pseudo-elements */
        .message::before {
            content: '';
            position: absolute;
            left: 15px;
            top: 50%;
            transform: translateY(-50%);
            font-weight: 900;
            font-size: 1.1em;
        }


        /* Toggle Link Styling */
        .toggle-link {
            margin-top: 25px;
            color: var(--primary-color);
            cursor: pointer;
            text-decoration: none; /* Remove default underline */
            font-weight: 500;
            display: inline-block; /* Allows better spacing/hover */
            transition: color 0.2s ease;
        }
        .toggle-link:hover {
            color: var(--primary-hover-color);
            text-decoration: underline; /* Underline on hover */
        }

        /* Signup Form Initial State */
        #signupForm {
            display: none;
        }
         /* Note Styling */
         #signupForm p {
            font-size: 0.85em;
            color: #6c757d; /* Bootstrap muted color */
            margin-bottom: 15px;
         }