Adding a font size to a script

JavaScript
1

I run a website called I have a script which needs a font size change as it appears too small. I am a complete numpty and have no idea if any one can help me.and the script appears on the homepage. I am 72 and fading, I need an answer not a strategy. I imagine most programmers will see this as pathetic but is important to me!

Here is the script

 <SCRIPT LANGUAGE=Javascript>
<!--
/*
 Java Script Calendar is a small script for web pages which displays current Day of the week, Month, Date and Year along with Holidays notification. Just like this working demo below. It will work with Netscape 2++, Microsoft 3++ and Opera 3++ web browsers.

                                    Tuesday, November 24, 1998    

About 70 holidays from all over the world are displayed by Calendar (if you know other ones, let me know, I will add them). It even calculates Easter Sunday date! To see how it works change the date on your computer to January, 1,
for example and re-load the page.

Installation is very simple. Just copy the script below, everything between SCRIPT and SCRIPT tags (including tags themselves) and paste in the place you want it to appear on your page. You can customize the way
 it looks by changing document.write function arguments just after month names definitions. Java Script Calendar is free without any limitations. Copyright © Eugene Vassiltsov. But please, let me know if you will use it.
*/

 calendar = new Date();
 day = calendar.getDay();
 month = calendar.getMonth();
 date = calendar.getDate();
 year = calendar.getYear();
 if (year < 1000)
 year+=1900
 cent = parseInt(year/100);
 g = year % 19;
 k = parseInt((cent - 17)/25);
 i = (cent - parseInt(cent/4) - parseInt((cent - k)/3) + 19*g + 15) % 30;
 i = i - parseInt(i/28)*(1 - parseInt(i/28)*parseInt(29/(i+1))*parseInt((21-g)/11));
 j = (year + parseInt(year/4) + i + 2 - cent + parseInt(cent/4)) % 7;
 l = i - j;
 emonth = 3 + parseInt((l + 40)/44);
 edate = l + 28 - 31*parseInt((emonth/4));
 emonth--;
 var dayname = new Array ("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday");
 var monthname = 
 new Array ("January","February","March","April","May","June","July","August","September","October","November","December" );
 document.write("");
 document.write(dayname[day] + ", ");
 document.write(monthname[month] + " ");
 if (date< 10) document.write("0" + date + ", ");
         else document.write(date + ", ");




 // July
if ((month == 6) && (date == 1)) document.write("1873, Isle of Man Railway Opened from Douglas to Peel");
if ((month == 6) && (date == 2)) document.write("1940, Christopher Awdry, Childrens railway author born");

 // August

if ((month == 7) && (date == 1)) document.write("1828, The Bolton and Leigh Railway opened to freight traffic");
 if ((month == 7) && (date == 2)) document.write("1987, Gloucester and Warwick railway reopened Winchcombe Station");
 

 // September
 if ((month == 8) && (date == 1)) document.write("1854, Opening of first railway in Norway");
 if ((month == 8) && (date == 2)) document.write("1898, Wellingborough Station Tragedy");



 // October
 if ((month == 9) && (date == 1)) document.write("1868, London St. Pancras Station Opened");
 if ((month == 9) && (date == 2)) document.write("1865, Alton, Alresford & Winchester Railway opened");
 if ((month == 9) && (date == 3)) document.write("1839, First railway line in Italy opened");

 // November
 if ((month == 10) && (date == 1)) document.write("1848, First W H Smith bookstall opens, at Euston Station [1848]");
 if ((month == 10) && (date == 2)) document.write("1896, Highland Railway's Kyle of Lochalsh Line completed [1896]");
if ((month == 10) && (date == 3)) document.write("1969, Kansas City Southern's Southern Belle passenger train service between Kansas City  and New Orleans  made its final run [1969]");


 if ((month == 10) && (date == 29)) document.write("1844, Dublin Railway station opened");
 if ((month == 10) && (date == 30)) document.write("1934, Flying Scotsman becomes first steam loco to reach 100mph");


 // December
 if ((month == 11) && (date == 1)) document.write("1869, Liverpool Union Railway Opened via Huyton and Prescot up to Wigan ");

 if ((month == 11) && (date == 31)) document.write("1932, Last steam-powered Southern Belle passenger train operated by Southern Railway");

 document.write("<br />");
//-->
 </SCRIPT>
2

Hi there!

Post your code here, use three back ticks (```) on a separate line before and after your code block.

3

Because it writes to the body, the body font size is the only place you can change the font size, and that will affect all other text on the page that is inheriting the font size from the body.

Here is an updated version that inserts a paragraph element instead. At the bottom, you can set the font size to whatever you want. I added a comment showing how to add new events as well.

Script 
<script>
    const calendar = new Date();
    const day = calendar.getDay();
    const month = calendar.getMonth();
    const date = calendar.getDate();
    let year = calendar.getYear();
    if (year < 1000) year += 1900;
    const cent = parseInt(year / 100);
    const g = year % 19;
    const k = parseInt((cent - 17) / 25);
    let i =
      (cent - parseInt(cent / 4) - parseInt((cent - k) / 3) + 19 * g + 15) % 30;
    i =
      i -
      parseInt(i / 28) *
        (1 -
          parseInt(i / 28) * parseInt(29 / (i + 1)) * parseInt((21 - g) / 11));
    const j =
      (year + parseInt(year / 4) + i + 2 - cent + parseInt(cent / 4)) % 7;
    const l = i - j;
    let emonth = 3 + parseInt((l + 40) / 44);
    const edate = l + 28 - 31 * parseInt(emonth / 4);
    emonth--;

    const dayname = [
      "Sunday",
      "Monday",
      "Tuesday",
      "Wednesday",
      "Thursday",
      "Friday",
      "Saturday",
    ];

    const monthname = [
      "January",
      "February",
      "March",
      "April",
      "May",
      "June",
      "July",
      "August",
      "September",
      "October",
      "November",
      "December",
    ];

    const message = document.createElement("p");

    message.textContent = "";
    message.textContent += dayname[day] + ", ";
    message.textContent += monthname[month] + " ";
    if (date < 10) message.textContent += "0" + date + ", ";
    else message.textContent += date + ", ";

    /*
     ** Add new events like this:
     if (month == 0 && date == 1) message.textContent += "Event";
    */

    // July
    if (month == 6 && date == 1)
      message.textContent +=
        "1873, Isle of Man Railway Opened from Douglas to Peel";
    if (month == 6 && date == 2)
      message.textContent +=
        "1940, Christopher Awdry, Childrens railway author born";

    // August
    if (month == 7 && date == 1)
      message.textContent +=
        "1828, The Bolton and Leigh Railway opened to freight traffic";
    if (month == 7 && date == 2)
      message.textContent +=
        "1987, Gloucester and Warwick railway reopened Winchcombe Station";

    // September
    if (month == 8 && date == 1)
      message.textContent += "1854, Opening of first railway in Norway";
    if (month == 8 && date == 2)
      message.textContent += "1898, Wellingborough Station Tragedy";

    // October
    if (month == 9 && date == 1)
      message.textContent += "1868, London St. Pancras Station Opened";
    if (month == 9 && date == 2)
      message.textContent +=
        "1865, Alton, Alresford & Winchester Railway opened";
    if (month == 9 && date == 3)
      message.textContent += "1839, First railway line in Italy opened";

    // November
    if (month == 10 && date == 1)
      message.textContent +=
        "1848, First W H Smith bookstall opens, at Euston Station [1848]";
    if (month == 10 && date == 2)
      message.textContent +=
        "1896, Highland Railway's Kyle of Lochalsh Line completed [1896]";
    if (month == 10 && date == 3)
      message.textContent +=
        "1969, Kansas City Southern's Southern Belle passenger train service between Kansas City  and New Orleans  made its final run [1969]";

    if (month == 10 && date == 29)
      message.textContent += "1844, Dublin Railway station opened";
    if (month == 10 && date == 30)
      message.textContent +=
        "1934, Flying Scotsman becomes first steam loco to reach 100mph";

    // December
    if (month == 11 && date == 1)
      message.textContent +=
        "1869, Liverpool Union Railway Opened via Huyton and Prescot up to Wigan ";

    if (month == 11 && date == 31)
      message.textContent +=
        "1932, Last steam-powered Southern Belle passenger train operated by Southern Railway";

    // set the font size here
    message.style.fontSize = "2rem";

    document.body.insertAdjacentElement("beforeend", message);
    document.body.insertAdjacentHTML("beforeend", "<br>");
  </script>