Centre H1 titles

Hi there, although our h1 tags centre on desktop, for some reason on mobile they are left aligned. So “silver bangles” will be centre when viewed on desktop, but then left aligned on mobile – any ideas why this is happening and how we can make them centred on mobile?

We have added the following css but it doesn’t seem to do anything on mobile: –

h1 {
text-align: center;
}

Many thanks

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