/* Copyright 2020 The golang.design Initiative.
   All rights reserved. Use of this source code
   is governed by a MIT license that can be found
   in the LICENSE file.

   Shared by Go: A Documentary and the runtime and compiler history. */

:root {
  --bg: #fbfbf9;
  --fg: #1c1d1f;
  --mut: #5f615c;
  --faint: #8a8c86;
  --line: #e5e3dd;
  --side: #f4f3ef;
  --code: #efede7;
  --acc: #007d9c;
  --acc-bg: rgba(0, 125, 156, .08);
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial,
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --hdr: 52px;
  --side-w: 288px;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #141518;
  --fg: #e6e5e0;
  --mut: #a5a49d;
  --faint: #7e7d77;
  --line: #2b2d31;
  --side: #191a1e;
  --code: #23252a;
  --acc: #5dc9e2;
  --acc-bg: rgba(93, 201, 226, .1);
  color-scheme: dark;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #141518;
    --fg: #e6e5e0;
    --mut: #a5a49d;
    --faint: #7e7d77;
    --line: #2b2d31;
    --side: #191a1e;
    --code: #23252a;
    --acc: #5dc9e2;
    --acc-bg: rgba(93, 201, 226, .1);
    color-scheme: dark;
  }
}

/* Base */

* { box-sizing: border-box; }
html { scroll-padding-top: calc(var(--hdr) + 16px); -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.65 var(--sans);
  overflow-wrap: break-word;
}
a { color: var(--acc); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 2px; }
img { max-width: 100%; }
code, kbd, pre { font-family: var(--mono); }
code { font-size: .875em; background: var(--code); padding: .1em .35em; border-radius: 4px; overflow-wrap: anywhere; }
pre { background: var(--code); padding: 12px 14px; border-radius: 6px; overflow-x: auto; font-size: 14px; line-height: 1.5; }
pre code { background: none; padding: 0; font-size: inherit; }
hr { border: 0; border-top: 1px solid var(--line); margin: 32px 0; }
button { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--acc); outline-offset: 2px; border-radius: 3px; }

/* Header */

.site {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 24px;
  height: var(--hdr);
  padding: 0 20px;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}
.site .brand { color: var(--fg); font-weight: 650; font-size: 15.5px; letter-spacing: -.01em; white-space: nowrap; }
.site .brand:hover { text-decoration: none; color: var(--acc); }
.site .tabs { display: flex; gap: 4px; height: 100%; }
.site .tabs a {
  display: flex;
  align-items: center;
  padding: 0 10px;
  color: var(--mut);
  font-size: 14px;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
}
.site .tabs a:hover { color: var(--fg); text-decoration: none; }
.site .tabs a[aria-current] { color: var(--fg); border-bottom-color: var(--acc); }
.site .tools { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.site .tools .lang { font-size: 14px; color: var(--mut); padding: 6px 10px; border-radius: 6px; }
.site .tools .lang:hover { background: var(--side); color: var(--fg); text-decoration: none; }
.icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  padding: 0;
  border: 0;
  border-radius: 6px;
  background: none;
  color: var(--mut);
  cursor: pointer;
}
.icon:hover { background: var(--side); color: var(--fg); }
.icon svg { width: 18px; height: 18px; }
.site .menu { display: none; margin-left: -8px; }
.theme .i-light, .theme .i-dark { display: none; }
:root[data-theme="light"] .theme .i-auto, :root[data-theme="dark"] .theme .i-auto { display: none; }
:root[data-theme="light"] .theme .i-light, :root[data-theme="dark"] .theme .i-dark { display: block; }

/* Layout */

.layout { display: grid; grid-template-columns: var(--side-w) minmax(0, 1fr); }
.side {
  position: sticky;
  top: var(--hdr);
  height: calc(100vh - var(--hdr));
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 18px 14px 64px;
  background: var(--side);
  border-right: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.45;
}
main { min-width: 0; max-width: 860px; padding: 40px 56px 96px; }

/* Sidebar */

.side ul { list-style: none; margin: 0; padding: 0; }
.side a { display: block; padding: 4px 8px; border-radius: 5px; color: var(--fg); }
.side a:hover { background: var(--line); text-decoration: none; }
.side a[aria-current="page"] { color: var(--acc); font-weight: 600; }
.side .toc > ul > li { margin: 1px 0; }
.side .toc ul ul { margin: 2px 0 8px 8px; padding-left: 8px; border-left: 1px solid var(--line); }
.side .toc ul ul a { color: var(--mut); font-size: 13px; padding: 2px 8px; }
.side .toc ul ul a:hover { color: var(--fg); }
.side .toc ul ul ul { margin: 0 0 4px 8px; }
.side .group {
  margin: 20px 8px 6px;
  color: var(--faint);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
}

/* Search */

.search { position: relative; margin: 0 0 14px; }
.search svg { position: absolute; left: 9px; top: 50%; width: 15px; height: 15px; transform: translateY(-50%); color: var(--faint); pointer-events: none; }
.search input {
  width: 100%;
  padding: 7px 30px 7px 30px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--bg);
  color: var(--fg);
  font: 14px var(--sans);
  -webkit-appearance: none;
  appearance: none;
}
.search input::placeholder { color: var(--faint); }
.search input:focus { outline: none; border-color: var(--acc); box-shadow: 0 0 0 3px var(--acc-bg); }
.search input::-webkit-search-cancel-button { display: none; }
.search kbd {
  position: absolute;
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
  padding: 0 5px;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--faint);
  font-size: 11px;
  line-height: 16px;
}
.search input:focus + kbd, .search input:not(:placeholder-shown) + kbd { display: none; }
.results { margin: 0; padding: 0; list-style: none; }
.results .count { color: var(--faint); font-size: 12.5px; padding: 0 8px 6px; }
.results a { padding: 6px 8px; color: var(--fg); }
.results a .ref { margin-right: 4px; }
.results small { display: block; color: var(--faint); font-size: 12px; margin-top: 1px; }

/* Content */

main h1, main h2, main h3, main h4 { line-height: 1.25; letter-spacing: -.01em; position: relative; }
main h1 { font-size: 2rem; font-weight: 700; margin: 0 0 16px; }
main h2 { font-size: 1.45rem; font-weight: 650; margin: 56px 0 14px; padding-top: 20px; border-top: 1px solid var(--line); }
main h3 { font-size: 1.15rem; font-weight: 650; margin: 36px 0 10px; }
main h4 { font-size: 1rem; font-weight: 650; margin: 28px 0 8px; color: var(--mut); }
main h1 + h2 { border-top: 0; padding-top: 0; margin-top: 32px; }
.anchor { margin-left: 8px; color: var(--faint); font-weight: 400; opacity: 0; text-decoration: none; }
h1:hover .anchor, h2:hover .anchor, h3:hover .anchor, h4:hover .anchor, .anchor:focus { opacity: 1; }
.anchor:hover { color: var(--acc); text-decoration: none; }
main p { margin: 0 0 14px; }
main ul, main ol { margin: 0 0 16px; padding-left: 22px; }
main li { margin: 5px 0; }
main li > ul, main li > ol { margin: 4px 0 6px; }
main li::marker { color: var(--faint); }
main blockquote { margin: 16px 0; padding: 2px 16px; border-left: 3px solid var(--line); color: var(--mut); }
main table { border-collapse: collapse; margin: 16px 0 24px; font-size: 14.5px; font-variant-numeric: tabular-nums; display: block; overflow-x: auto; }
main th, main td { padding: 7px 14px 7px 0; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
main th { font-weight: 600; color: var(--mut); font-size: 13px; border-bottom-width: 2px; }
main details summary { cursor: pointer; }
main details summary::marker { color: var(--faint); }
main details[open] summary { margin-bottom: 6px; }
main details p { color: var(--mut); font-size: 14.5px; }
.lede { font-size: 1.075rem; color: var(--mut); }

/* Entry labels such as issue/12345 or design/go13compiler */

.ref { font-family: var(--mono); font-size: .8em; color: var(--mut); overflow-wrap: anywhere; }
.ref:hover { color: var(--acc); }
main li > .ref, main li > p > .ref { margin-right: 2px; }

/* Home page contents */

.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(232px, 1fr)); gap: 12px; margin: 28px 0 8px; }
.card {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--fg);
  transition: border-color .12s;
}
.card:hover { border-color: var(--acc); text-decoration: none; }
.card b { font-weight: 650; }
.card span { color: var(--mut); font-size: 13.5px; line-height: 1.5; display: -webkit-box; -webkit-box-orient: vertical; -webkit-line-clamp: 3; overflow: hidden; }
.card small { margin-top: auto; padding-top: 6px; color: var(--faint); font-size: 12.5px; }
.card.feature { grid-column: 1 / -1; border-color: var(--acc); background: var(--acc-bg); }
.card.feature b::after { content: " →"; color: var(--acc); }

/* Page footer */

.pager { display: flex; justify-content: space-between; gap: 16px; margin: 64px 0 0; padding-top: 20px; border-top: 1px solid var(--line); }
.pager a { display: flex; flex-direction: column; max-width: 48%; color: var(--fg); font-weight: 600; }
.pager a small { color: var(--faint); font-weight: 400; font-size: 12.5px; }
.pager a:hover { color: var(--acc); text-decoration: none; }
.pager .next { margin-left: auto; text-align: right; }
.foot { margin-top: 40px; color: var(--faint); font-size: 13px; }
.foot a { color: var(--mut); }

/* Narrow screens */

@media (max-width: 900px) {
  .site { gap: 12px; padding: 0 12px; }
  .site .menu { display: inline-flex; }
  .site .tabs { display: none; }
  .layout { display: block; }
  .side {
    position: fixed;
    top: var(--hdr);
    left: 0;
    bottom: 0;
    z-index: 20;
    width: min(var(--side-w), 86vw);
    height: auto;
    transform: translateX(-100%);
    transition: transform .18s ease;
    box-shadow: none;
  }
  .nav-open .side { transform: none; box-shadow: 0 0 0 100vmax rgba(0, 0, 0, .28); }
  main { padding: 24px 18px 72px; }
  main h1 { font-size: 1.65rem; }
}

@media print {
  .site, .side, .pager { display: none; }
  .layout { display: block; }
  main { max-width: none; padding: 0; }
}