Auto merge of #77981 - GuillaumeGomez:rollup-64ydc5g, r=GuillaumeGomez

Rollup of 3 pull requests

Successful merges:

 - #77963 (Fix link to foreign calling conventions)
 - #77978 (Fix typo in documentation)
 - #77979 (Hide help button on mobile)

Failed merges:

r? `@ghost`

library/alloc/src/boxed.rs

@@ -815,7 +815,7 @@ impl From<Cow<'_, str>> for Box<str> {
 
 #[stable(feature = "boxed_str_conv", since = "1.19.0")]
 impl From<Box<str>> for Box<[u8]> {
-    /// Converts a `Box<str>>` into a `Box<[u8]>`
+    /// Converts a `Box<str>` into a `Box<[u8]>`
     ///
     /// This conversion does not allocate on the heap and happens in place.
     ///

library/std/src/primitive_docs.rs

@@ -1118,6 +1118,8 @@ mod prim_ref {}
 /// For more information and a list of supported ABIs, see [the nomicon's
 /// section on foreign calling conventions][nomicon-abi].
 ///
+/// [nomicon-abi]: ../nomicon/ffi.html#foreign-calling-conventions
+///
 /// ### Variadic functions
 ///
 /// Extern function declarations with the "C" or "cdecl" ABIs can also be *variadic*, allowing them

src/librustdoc/html/static/rustdoc.css

@@ -1540,6 +1540,14 @@ h4 > .notable-traits {
 		left: 0;
 		top: 100%;
 	}
+
+	/* We don't display the help button on mobile devices. */
+	.help-button {
+		display: none;
+	}
+	.search-container > div {
+		width: calc(100% - 32px);
+	}
 }
 
 @media print {