В чём заключается ошибка? server is not defined at HTMLAnchorElement.

Вот код программы

        const weatherBlock = document.querySelector('#weather');

async function loadWeather(e){

    weatherBlock.innerHTML = `
    <div class="weather_loading">
         <img src="./img/loading.gif" alt="Loading">
    </div> 
    `;

    var server = 'https://api.openweathermap.org/data/2.5/weather?&units=metric&q=Lviv&appid=574e986eeab53f684105869f71a44fe3';

    const response = await fetch(server, {
        method:'GET',
    })

    const responseResult = await response.json();

    if(response.ok){
        getWeather(responseResult)
    }else{
        weatherBlock.innerHTML = responseResult.message;
    }

}

function getWeather(data){
    console.log(data);

    const location = data.name;
    const temp = Math.round(data.main.temp);
    const feelsLike = Math.round(data.main.feels_like);
    const weatherStatus = data.weather[0].main;
    const weatherIcon = data.weather[0].icon;


    const template = `
    <div class="weather_header">
        <div class="weather_main">
            <div class="weather_city">
                ${location}
            </div>
            <div class="weather_status">
                ${weatherStatus}
            </div>
        </div>
        <!-- /weather_main -->
        <div class="weather_icon">
            <img src="https://openweathermap.org/img/w/${weatherIcon}.png" alt="CLouds">
        </div>
        <!-- /weather_icon -->
    </div>
    <!-- /weather_header -->
    <div class="weather_temp">${temp}</div>
     <div class="weather_feels-like">Feels like: ${feelsLike}</div>`;

    weatherBlock.innerHTML = template;
    const Lviv = document.querySelector('.Lviv');
    const Kyiv = document.querySelector('.Kyiv');
    
    const Warsaw = document.querySelector('.Warsaw');

    Lviv.addEventListener('click', () =>{
        server = 'https://api.openweathermap.org/data/2.5/weather?&units=metric&q=Lviv&appid=574e986eeab53f684105869f71a44fe3';
    });
    Kyiv.addEventListener('click', () =>{
             server = 'https://api.openweathermap.org/data/2.5/weather?&units=metric&q=Kyiv&appid=574e986eeab53f684105869f71a44fe3';
    })
    Warsaw.addEventListener('click', () =>{
        server = 'https://api.openweathermap.org/data/2.5/weather?&units=metric&q=Warsaw&appid=574e986eeab53f684105869f71a44fe3';
    })
}
if(weatherBlock){
    loadWeather();
}