关于站点主页的副标题显示效果较弱的问题

[Anyexyz]

站点主页的副标题设置后，本身副标题的相较于主标题的大小较小，由于背景图片的设置，副标题设置透明度50%容易使副标题看不清，建议设置为100%。
修改建议hero.html35行

<span class="text-sm font-light text-white opacity-50" th:text="${site.subtitle}"></span>

修改为

<span class="text-sm font-light text-white opacity-100" th:text="${site.subtitle}"></span>

[JohnNiang]

/kind improvement
/good-first-issue

[f2c-ci-robot]

@JohnNiang:
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In response to this:

/kind improvement
/good-first-issue

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[DeanLiu0521]

你好，第一次尝试contribute，想领取这个issue。