feat: switch to windicss (#65)

src/styles/main.css

@@ -0,0 +1,43 @@
+@import './markdown.css';
+
+html,
+body,
+#app {
+  height: 100vh;
+  margin: 0;
+  padding: 0;
+}
+
+html.dark {
+  background: #222;
+}
+
+#nprogress {
+  pointer-events: none;
+}
+
+#nprogress .bar {
+  @apply bg-teal-600 opacity-75;
+
+  position: fixed;
+  z-index: 1031;
+  top: 0;
+  left: 0;
+
+  width: 100%;
+  height: 2px;
+}
+
+.btn {
+  @apply px-4 py-1 rounded inline-block
+    bg-teal-600 text-white cursor-pointer
+    hover:bg-teal-700
+    disabled:cursor-default disabled:bg-gray-600 disabled:opacity-50;
+}
+
+.icon-btn {
+  @apply inline-block cursor-pointer select-none
+    opacity-75 transition duration-200 ease-in-out
+    hover:opacity-100 hover:text-teal-600;
+  font-size: 0.9em;
+}