mkdocs-material/src/assets/stylesheets/layout/_nav.scss

/*
 * Copyright (c) 2016 Martin Donath <martin.donath@squidfunk.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

/* ----------------------------------------------------------------------------
 * Navigation
 * ------------------------------------------------------------------------- */

/*
 * Nested navigation
 */
.md-nav {

  /*
   * Set font sizes
   */
  &, h3 {
    font-size: ms(-1);
    line-height: 1.2;
  }

  /*
   * Table of contents
   */
  &--toc {
    border-left: px2rem(4px) solid $md-color-primary;
  }

  /*
   * List of items
   */
  &__list {
    list-style: none;

    /*
     * 2nd+ level list
     */
    & & {
      margin-left: 1.2rem;
    }

    /*
     * Hide list by default
     */
    .md-nav__toggle ~ & {
      max-height: 0;
      overflow: hidden;
    }

    /*
     * Expand list, if toggle is checked
     */
    .md-nav__toggle:checked ~ & {
      max-height: 100%;
    }
  }

  /*
   * List item
   */
  &__item {
    margin: 0.8rem 0 0;
    line-height: 1.6rem;
  }

  /*
   * Link inside item
   */
  &__link {
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: color .125s;

    /*
     * Marked item
     */
    &--marked {
      color: $md-color-black--light;
    }

    /*
     * Current or hovered item
     */
    &:hover,
    &:active,
    &--active {
      color: $md-color-accent;
    }
  }
}