const darkModeToggle = document.getElementById('dark-mode-toggle');
const themeIcon = darkModeToggle.querySelector('.theme-icon');
const themeLabel = darkModeToggle.querySelector('.theme-label');

function applyTheme(isDark) {
    document.body.classList.toggle('dark-mode', isDark);
    darkModeToggle.setAttribute('aria-pressed', String(isDark));
    themeIcon.textContent = isDark ? '☀' : '☾';
    themeLabel.textContent = isDark ? 'Light mode' : 'Dark mode';
    document.querySelector('meta[name="theme-color"]').content = isDark ? '#0d1828' : '#e9f3fb';
    window.dispatchEvent(new Event('themechange'));
}

let savedTheme;
try {
    savedTheme = localStorage.getItem('darkMode');
} catch {
    savedTheme = null;
}

applyTheme(savedTheme === 'enabled' || (savedTheme === null && window.matchMedia('(prefers-color-scheme: dark)').matches));

darkModeToggle.addEventListener('click', () => {
    const isDark = !document.body.classList.contains('dark-mode');
    applyTheme(isDark);
    try {
        localStorage.setItem('darkMode', isDark ? 'enabled' : 'disabled');
    } catch {
        // The chosen theme remains active for this visit when storage is unavailable.
    }
});