<style>
        :root {
            --bg-color: #f0f0f0;
            --text-color: #333;
            --card-bg: #fff;
            --shadow: 0 2px 5px rgba(0,0,0,0.1);
        }

        .dark-mode {
            --bg-color: #333;
            --text-color: #f0f0f0;
            --card-bg: #444;
            --shadow: 0 2px 5px rgba(255,255,255,0.1);
        }

        body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 20px;
            background-color: var(--bg-color);
            color: var(--text-color);
            transition: background-color 0.3s, color 0.3s;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            background-color: var(--card-bg);
            padding: 20px;
            border-radius: 8px;
            box-shadow: var(--shadow);
        }
        h1 {
            text-align: center;
            color: var(--text-color);
        }
        #loginForm, #registerForm, #todoForm, #taskList {
            margin-bottom: 20px;
        }
        input, select, button {
            width: 100%;
            padding: 10px;
            margin-bottom: 10px;
            border: 1px solid #ddd;
            border-radius: 4px;
            box-sizing: border-box;
        }
        button {
            background-color: #4CAF50;
            color: white;
            border: none;
            cursor: pointer;
            transition: background-color 0.3s;
        }
        button:hover {
            background-color: #45a049;
        }
        .task {
            padding: 15px;
            margin-bottom: 15px;
            border-radius: 8px;
            box-shadow: var(--shadow);
            transition: transform 0.3s, box-shadow 0.3s;
            cursor: move;
        }
        .task:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }
        .task button {
            width: auto;
            padding: 5px 10px;
            margin-left: 10px;
        }
        @media (max-width: 600px) {
            .container {
                padding: 10px;
            }
        }
        .Krys_Rx { background-color: #FFE4E1; }
        .Yann { background-color: #E6F3FF; }
        .Yas { background-color: #F0FFF0; }
        .Gul { background-color: #FFF5E6; }

        .status-todo { border-left: 5px solid #FFFFFF; }
        .status-in-progress { border-left: 5px solid #FFFACD; }
        .status-done { border-left: 5px solid #90EE90; }

        .edit-dialog {
            position: fixed;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            background-color: var(--card-bg);
            padding: 20px;
            border-radius: 8px;
            box-shadow: 0 0 10px rgba(0,0,0,0.3);
            z-index: 1000;
        }
        .edit-dialog input, .edit-dialog select {
            width: 100%;
            margin-bottom: 10px;
        }
        .edit-dialog button {
            margin-right: 10px;
        }
        .user-section {
            margin-bottom: 20px;
            padding: 10px;
            border-radius: 8px;
        }
        .kanban-board {
            display: flex;
            justify-content: space-between;
            overflow-x: auto;
        }
        .kanban-column {
            flex: 1;
            min-width: 250px;
            margin: 0 10px;
            background-color: var(--card-bg);
            border-radius: 8px;
            padding: 10px;
        }
        .filters {
            display: flex;
            justify-content: space-between;
            margin-bottom: 20px;
        }
        .filters select, .filters input {
            width: auto;
        }
        #darkModeToggle {
            position: fixed;
            top: 10px;
            right: 10px;
            z-index: 1001;
        }
        @keyframes fadeIn {
            from { opacity: 0; }
            to { opacity: 1; }
        }
        .task {
            animation: fadeIn 0.5s;
        }
    </style>