Selenium WebDriver - Finding Elements using cssSelector and nth child

do you need css specifically? if not, you can also go for xpath, which imho reads better/clearer:

driver.findElement(By.xpath("(//span[@class='title'])[0]")); // home
driver.findElement(By.xpath("(//span[@class='title'])[1]")); // posts
...

You can generate the css-selector from ul like ul > li:nth-child(1) for home. See below:

driver.findElement(By.cssSelector("ul > li:nth-child(1)")); >> home
driver.findElement(By.cssSelector("ul > li:nth-child(2)")); >> posts
driver.findElement(By.cssSelector("ul > li:nth-child(3)")); >> events

also reachin span is the same:

driver.findElement(By.cssSelector("ul > li:nth-child(1) > a > span")); >> home