The link hint some time use default

I don't known why but link hint on my browser sometimes uses the default theme.
I must use the more specific css matching from other vimium theme to solve this problem.
This is my change:
```
/* Link hint boxes */
#vimiumHintMarkerContainer div.internalVimiumHintMarker, #vimiumHintMarkerContainer div.vimiumHintMarker {
background: #282a36;
font-size: 12px;
border: 0.25em solid #ffb86c;
border-radius: 0.34em;
box-shadow: 0em 0.1em 0.6em 0.1em rgba(0, 0, 0, 0.4);
}

/* Link hint text */
#vimiumHintMarkerContainer div span {
color: #f8f8f2;
font-size: inherit;
text-shadow: none;
}

/* Link hint matching characters */
#vimiumHintMarkerContainer div > .matchingCharacter ~ span {
color: #6272a4;
}
```