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

        body {
            font-family: 'Arial', sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            padding: 20px;
        }

        .container {
            max-width: 800px;
            margin: 0 auto;
            background: white;
            border-radius: 15px;
            box-shadow: 0 20px 40px rgba(0,0,0,0.1);
            overflow: hidden;
        }

        .header {
            background: linear-gradient(45deg, #ff6b6b, #ffd93d);
            padding: 30px;
            text-align: center;
            color: white;
        }

        .header h1 {
            font-size: 2.5em;
            margin-bottom: 10px;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }

        .content {
            padding: 40px;
        }

        .section {
            margin-bottom: 40px;
            padding: 25px;
            border-radius: 10px;
            border-left: 5px solid #667eea;
            background: #f8f9fa;
        }

        .section h2 {
            color: #333;
            margin-bottom: 20px;
            font-size: 1.5em;
        }

        /* Botones */
        .btn {
            background: linear-gradient(45deg, #667eea, #764ba2);
            color: white;
            border: none;
            padding: 12px 25px;
            border-radius: 25px;
            cursor: pointer;
            font-size: 16px;
            margin: 5px;
            transition: all 0.3s ease;
            box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
        }

        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
        }

        .btn-danger {
            background: linear-gradient(45deg, #ff6b6b, #ee5a52);
        }

        .btn-success {
            background: linear-gradient(45deg, #51cf66, #40c057);
        }

        /* Panel oculto */
        .hidden-panel {
            background: linear-gradient(135deg, #ffeaa7, #fdcb6e);
            padding: 20px;
            border-radius: 10px;
            margin-top: 15px;
            display: none;
            animation: slideDown 0.5s ease;
        }

        @keyframes slideDown {
            from { opacity: 0; transform: translateY(-20px); }
            to { opacity: 1; transform: translateY(0); }
        }

        /* Formulario */
        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: bold;
            color: #333;
        }

        .form-group input, .form-group select {
            width: 100%;
            padding: 12px;
            border: 2px solid #ddd;
            border-radius: 8px;
            font-size: 16px;
            transition: border-color 0.3s ease;
        }

        .form-group input:focus, .form-group select:focus {
            outline: none;
            border-color: #667eea;
            box-shadow: 0 0 10px rgba(102, 126, 234, 0.2);
        }

        /* Lista dinámica */
        .task-list {
            min-height: 100px;
            border: 2px dashed #ddd;
            border-radius: 10px;
            padding: 20px;
            background: #f8f9fa;
        }

        .task-item {
            background: white;
            padding: 15px;
            margin: 10px 0;
            border-radius: 8px;
            border-left: 4px solid #667eea;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            display: flex;
            justify-content: space-between;
            align-items: center;
            animation: fadeIn 0.5s ease;
        }

        @keyframes fadeIn {
            from { opacity: 0; transform: translateX(-20px); }
            to { opacity: 1; transform: translateX(0); }
        }

        .delete-btn {
            background: #ff6b6b;
            color: white;
            border: none;
            margin-left: 10px;
            padding: 5px 10px;
            border-radius: 50%;
            cursor: pointer;
            font-size: 12px;
        }

        /* Contador */
        .counter-display {
            font-size: 3em;
            font-weight: bold;
            color: #667eea;
            text-align: center;
            margin: 20px 0;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
        }

        /* Galería de imágenes */
        .image-gallery {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
            gap: 15px;
            margin-top: 20px;
        }

        .image-item {
            height: 150px;
            background: linear-gradient(45deg, #a8e6cf, #88d8c0);
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-weight: bold;
            cursor: pointer;
            transition: transform 0.3s ease;
            box-shadow: 0 4px 15px rgba(0,0,0,0.1);
        }

        .image-item:hover {
            transform: scale(1.05);
        }

        /* Tema oscuro */
        .dark-theme {
            background: #2c3e50;
            color: white;
        }

        .dark-theme .container {
            background: #34495e;
        }

        .dark-theme .section {
            background: #3a4a5c;
            color: white;
        }

        .dark-theme .task-list {
            background: #3a4a5c;
            border-color: #555;
        }

        .dark-theme .task-item {
            background: #2c3e50;
            color: white;
        }

        /* Mensaje de resultado */
        .result-message {
            padding: 15px;
            border-radius: 8px;
            margin-top: 15px;
            font-weight: bold;
            text-align: center;
            display: none;
        }

        .result-success {
            background: #d4edda;
            color: #155724;
            border: 1px solid #c3e6cb;
        }

        .result-error {
            background: #f8d7da;
            color: #721c24;
            border: 1px solid #f5c6cb;
        }