:root {
  --paper: #f6f4ef;
  --paper-bright: #fcfbf8;
  --ink: #201e1a;
  --ink-soft: #6f6a60;
  --ink-faint: #a39d92;
  --line: #e6e1d6;
  --line-strong: #d0c9bc;
  --moss: #7e8c7b;
  --moss-deep: #55614e;
  --night: #151412;
  --content-width: 1240px;
  --gutter: clamp(1.25rem, 4vw, 4rem);
  --serif: "Iowan Old Style", "Noto Serif SC", "Songti SC", "STSong", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Helvetica Neue", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --ease: cubic-bezier(.32, 0, .18, 1);
}

* {
  box-sizing: border-box;
}

html {
  background: var(--paper);
  color: var(--ink);
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  min-height: 100svh;
  margin: 0;
  overflow-x: hidden;
  background: var(--paper);
  font-family: var(--sans);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
  text-underline-offset: .25em;
}

a:focus-visible {
  outline: 2px solid var(--moss-deep);
  outline-offset: 4px;
}

img {
  max-width: 100%;
}

.skip-link {
  position: fixed;
  z-index: 10;
  top: .75rem;
  left: .75rem;
  transform: translateY(-180%);
  padding: .6rem .85rem;
  border-radius: 6px;
  background: var(--night);
  color: var(--paper-bright);
  transition: transform .2s var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
}

.app-showcase-page {
  display: flex;
  flex-direction: column;
}

.app-header {
  display: flex;
  width: min(100%, var(--content-width));
  min-height: 5.5rem;
  align-items: center;
  gap: 2rem;
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.app-brand {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  width: 8.5rem;
}

.app-brand img {
  display: block;
  width: 100%;
  height: auto;
}

.app-navigation {
  display: flex;
  flex: 1;
  justify-content: center;
  gap: clamp(1rem, 3vw, 2.6rem);
  color: var(--ink-soft);
  font-size: .78rem;
  letter-spacing: .08em;
  white-space: nowrap;
}

.app-navigation a,
.back-link {
  position: relative;
  text-decoration: none;
}

.app-navigation a::after {
  position: absolute;
  right: 0;
  bottom: -.45rem;
  left: 0;
  height: 1px;
  transform: scaleX(0);
  transform-origin: right;
  background: var(--moss-deep);
  content: "";
  transition: transform .3s var(--ease);
}

.app-navigation a:hover::after,
.app-navigation a:focus-visible::after,
.app-navigation a[aria-current="page"]::after {
  transform: scaleX(1);
  transform-origin: left;
}

.app-navigation a[aria-current="page"] {
  color: var(--moss-deep);
}

.back-link {
  flex: 0 0 auto;
  color: var(--ink-soft);
  font-size: .74rem;
}

.back-link::before {
  margin-right: .45rem;
  color: var(--moss-deep);
  content: "↩";
}

#app-main {
  width: min(100%, var(--content-width));
  flex: 1;
  margin: 0 auto;
  padding: clamp(3.5rem, 8vw, 7rem) var(--gutter) clamp(5rem, 10vw, 9rem);
}

.app-page-heading {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(12rem, .38fr);
  gap: clamp(2rem, 8vw, 8rem);
  align-items: end;
  margin-bottom: clamp(2.5rem, 6vw, 5rem);
}

.app-stage {
  margin: 0 0 1.45rem;
  color: var(--moss-deep);
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .14em;
  line-height: 1.5;
  text-transform: uppercase;
}

.app-page-heading h1 {
  max-width: 14em;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(2.5rem, 5vw, 5.1rem);
  font-weight: 400;
  letter-spacing: -.04em;
  line-height: 1.12;
  text-wrap: balance;
}

.app-page-lede {
  max-width: 25rem;
  margin: 0;
  color: var(--ink-soft);
  font-family: var(--serif);
  font-size: clamp(1.2rem, 2vw, 1.65rem);
  line-height: 1.5;
}

.app-page-note {
  max-width: 23rem;
  margin: 1.3rem 0 0;
  color: var(--ink-faint);
  font-size: .78rem;
  line-height: 1.7;
}

.app-artifact {
  margin: 0;
}

.artifact-frame {
  overflow: hidden;
  border: 1px solid var(--line-strong);
  border-radius: 22px;
  background: var(--paper-bright);
  box-shadow: 0 24px 64px rgba(32, 30, 26, .13);
}

.artifact-frame img {
  display: block;
  width: 100%;
  height: auto;
}

.app-artifact figcaption {
  margin-top: .85rem;
  color: var(--ink-faint);
  font-family: var(--mono);
  font-size: .65rem;
  letter-spacing: .06em;
}

.page-understand .artifact-frame {
  border-color: #4b5148;
  background: var(--night);
  box-shadow: 0 24px 64px rgba(21, 20, 18, .22);
}

.app-pager {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(3rem, 7vw, 6rem);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--line);
}

.app-pager a {
  display: flex;
  min-height: 8rem;
  flex-direction: column;
  justify-content: center;
  gap: .5rem;
  padding: 1.2rem 1.5rem;
  background: var(--paper);
  text-decoration: none;
  transition: background .3s var(--ease), color .3s var(--ease);
}

.app-pager a:last-child {
  align-items: flex-end;
  text-align: right;
}

.app-pager a:hover,
.app-pager a:focus-visible {
  background: var(--paper-bright);
  color: var(--moss-deep);
}

.app-pager span {
  color: var(--ink-faint);
  font-family: var(--mono);
  font-size: .64rem;
  letter-spacing: .1em;
  text-transform: uppercase;
}

.app-pager strong {
  font-family: var(--serif);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 400;
}

.app-footer {
  display: flex;
  flex-wrap: wrap;
  gap: .35rem 1rem;
  width: min(100%, var(--content-width));
  margin: 0 auto;
  padding: 1.3rem var(--gutter) 2rem;
  color: var(--ink-faint);
  font-family: var(--mono);
  font-size: .65rem;
  letter-spacing: .05em;
}

.app-footer a {
  border-bottom: 1px solid rgba(34, 31, 27, .18);
  color: inherit;
  text-decoration: none;
}

.app-footer a:hover,
.app-footer a:focus-visible {
  border-color: currentColor;
  color: var(--ink);
}

@media (max-width: 760px) {
  .app-header {
    min-height: auto;
    align-items: flex-start;
    flex-wrap: wrap;
    padding-top: 1.25rem;
    padding-bottom: 1.25rem;
  }

  .app-brand {
    width: 7.5rem;
  }

  .back-link {
    margin-left: auto;
    padding-top: .2rem;
  }

  .app-navigation {
    order: 3;
    width: 100%;
    justify-content: flex-start;
    overflow-x: auto;
    padding: .85rem 0 .25rem;
    scrollbar-width: none;
  }

  .app-navigation::-webkit-scrollbar {
    display: none;
  }

  #app-main {
    padding-top: 3.5rem;
  }

  .app-page-heading {
    display: block;
    margin-bottom: 2.4rem;
  }

  .app-page-heading h1 {
    max-width: none;
    font-size: clamp(2.25rem, 10vw, 3.5rem);
    white-space: normal;
  }

  .app-page-lede {
    margin-top: 1.2rem;
    font-size: 1.25rem;
  }

  .artifact-frame {
    border-radius: 14px;
  }

  .app-pager {
    grid-template-columns: 1fr;
  }

  .app-pager a:last-child {
    align-items: flex-start;
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: .01ms !important;
  }
}