, Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
                margin: 0;
                padding: 0;
                background: var(--background-color);
                color: var(--text-color);
            }

            .header {
                background: var(--card-background);
                display: flex;
                justify-content: space-between;
                align-items: center;
                padding: 15px 20px;
                background-color: rgba(255, 255, 255, 0.9);
            