@font-face {
  font-family: pretendard;
  src: url("fonts/Pretendard-Regular.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: block;
}

:root {
  color-scheme: light;
  --paper: #f7f6f2;
  --ink: #1f1f1f;
  --line-color: #1f1f1f99;
  --line-width: 1px;
  --snow-opacity: 0.6;
  --header-height: 44px;
  --footer-height: 34px;
  --input-width: 40%;
}

/* theme: black */
/* ff=100% e6=90% cc=80% b3=70% 99=60% 80=50% */
body[data-theme="black"] {
  --paper: #121212;
  --ink: #f2f2f2;
  --line-color: rgba(242, 242, 242, 0.4);
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
}

body {
  min-height: 100vh;
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: pretendard, sans-serif;
  word-break: keep-all;
  text-align: left;
  overflow: hidden;
}

.page-shell {
  position: relative;
  height: 100vh;
  min-height: 100vh;
  display: grid;
  grid-template: var(--header-height) minmax(0, 1fr) var(--footer-height) / minmax(260px, 1fr) minmax(260px, var(--input-width));
  align-items: stretch;
  border: var(--line-width) solid var(--line-color);
}

.frame-header {
  grid-column: 1 / 3;
  grid-row: 1;
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 0 14px;
  border-bottom: var(--line-width) solid var(--line-color);
}

.about-trigger {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  border: 0;
  min-height: 24px;
  padding: 0;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font: inherit;
  letter-spacing: 0;
  line-height: 1;
  opacity: 0.72;
  transition: opacity 160ms ease, transform 160ms ease;
}

.about-trigger:hover,
.about-trigger:focus-visible {
  opacity: 1;
  transform: translateY(-1px);
}

.about-text {
  min-width: 0;
  margin: 0;
  overflow: hidden;
  color: var(--ink);
  font-size: 15px;
  line-height: 1;
  opacity: 0;
  text-overflow: ellipsis;
  white-space: nowrap;
  word-break: keep-all;
  text-align: left;
  pointer-events: none;
}

.theme-toggle,
.view-toggle {
  flex: 0 0 auto;
  width: 14px;
  height: 14px;
  border: 0;
  padding: 0;
  background: var(--ink);
  cursor: pointer;
  line-height: 0;
  transition: background 160ms ease, transform 160ms ease;
}

.theme-toggle {
  margin-left: auto;
  border-radius: 50%;
  opacity: 0.6;
}

.view-toggle {
  opacity: 0.6;
}

.view-toggle-square {
  border-radius: 0;
}

.view-toggle-triangle {
  width: 0;
  height: 0;
  border: 0;
  border-left: 7.5px solid transparent;
  border-right: 7.5px solid transparent;
  border-bottom: 14px solid var(--ink);
  background: transparent;
}

.theme-toggle:hover,
.theme-toggle:focus-visible,
.view-toggle:hover,
.view-toggle:focus-visible,
.view-toggle.is-active {
  transform: scale(1.12);
}

.view-toggle.is-active {
  opacity: 1;
}

.about-text.is-visible {
  opacity: 0.6;
}

.about-text.is-fading {
  animation-name: headerVanish;
  animation-timing-function: ease;
  animation-fill-mode: forwards;
}

.frame-footer {
  grid-column: 1 / 3;
  grid-row: 3;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 14px;
  padding: 0 14px 10px;
  border-top: var(--line-width) solid var(--line-color);
  color: var(--ink);
  font-size: 12px;
  line-height: 1;
  word-break: keep-all;
  text-align: left;
}

.frame-footer span {
  opacity: 0.6;
}

.snow-toggle {
  flex: 0 0 auto;
  align-self: center;
  width: 2.4em;
  margin-bottom: 4px;
  border: 0;
  padding: 0;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font: inherit;
  font-size: 32px;
  line-height: 1;
  opacity: 0.6;
  text-align: right;
  transition: opacity 160ms ease, transform 160ms ease;
}

.snow-toggle:hover,
.snow-toggle:focus-visible,
.snow-toggle.is-active {
  opacity: 1;
  transform: translateY(-1px);
}

.snow-pane,
.stage {
  position: relative;
  min-width: 0;
  min-height: 0;
  background: var(--paper);
}

.snow-pane {
  grid-column: 1;
  grid-row: 2;
  border-right: var(--line-width) solid var(--line-color);
  overflow: hidden;
}

.stage {
  grid-column: 2;
  grid-row: 2;
  padding: clamp(20px, 2.4vw, 36px);
  overflow-x: hidden;
  overflow-y: visible;
  outline: none;
}

.stage:focus-visible {
  box-shadow: inset 0 0 0 2px rgba(32, 35, 38, 0.22);
}

body[data-view="snow"] .page-shell,
body[data-view="input"] .page-shell {
  grid-template: var(--header-height) minmax(0, 1fr) var(--footer-height) / minmax(0, 1fr);
}

body[data-view="snow"] .frame-header,
body[data-view="snow"] .frame-footer,
body[data-view="input"] .frame-header,
body[data-view="input"] .frame-footer {
  grid-column: 1;
}

body[data-view="snow"] .snow-pane,
body[data-view="input"] .stage {
  grid-column: 1;
  grid-row: 2;
  border-right: 0;
  border-bottom: 0;
}

body[data-view="snow"] .stage,
body[data-view="input"] .snow-pane {
  position: fixed;
  left: -100vw;
  top: -100vh;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  visibility: hidden;
}

.prompt {
  position: absolute;
  inset: clamp(20px, 2.4vw, 36px);
  margin: 0;
  color: var(--ink);
  font-size: clamp(24px, 4vw, 40px);
  line-height: 1.4;
  opacity: 0.42;
  pointer-events: none;
}

.prompt.is-hidden {
  opacity: 0;
}

.snow-field {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.letters {
  display: block;
  min-height: 100%;
  max-width: 100%;
  color: var(--ink);
  font-size: clamp(24px, 4vw, 40px);
  line-height: 1.4;
  white-space: pre-wrap;
  word-break: keep-all;
  text-align: left;
  overflow-wrap: break-word;
  position: relative;
  z-index: 1;
}

.stage.is-active .letters::after {
  content: "";
  display: inline-block;
  width: 1px;
  height: 0.92em;
  margin-left: 2px;
  background: var(--ink);
  animation: blink 1s steps(1, end) infinite;
  vertical-align: -0.08em;
}

.letter {
  display: inline-block;
  min-width: 0.28em;
  animation-name: vanish;
  animation-timing-function: ease;
  animation-fill-mode: forwards;
  will-change: opacity;
}

.word {
  display: inline-block;
  white-space: nowrap;
  max-width: 100%;
  vertical-align: baseline;
}

.word.has-space {
  margin-right: 0.42em;
}

.letter.break {
  min-width: 0;
}

@keyframes vanish {
  0% {
    opacity: 1;
    color: var(--ink);
  }

  60% {
    opacity: 0.42;
    color: var(--ink);
  }

  100% {
    opacity: 0;
    color: var(--ink);
  }
}

@keyframes blink {
  0%,
  49% {
    opacity: 1;
  }

  50%,
  100% {
    opacity: 0;
  }
}

@keyframes headerVanish {
  0% {
    opacity: 0.6;
    color: var(--ink);
  }

  60% {
    opacity: 0.28;
    color: var(--ink);
  }

  100% {
    opacity: 0;
    color: var(--ink);
  }
}

#input {
  position: fixed;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.snow-dot {
  position: absolute;
  left: var(--x);
  top: -1.5em;
  color: var(--ink);
  font-size: clamp(24px, 4vw, 40px);
  line-height: 1;
  opacity: var(--snow-opacity);
  transform: translateX(-50%);
  animation: snowfall var(--duration) linear infinite;
  pointer-events: none;
}

.snow-dot.weather-snow {
  animation-iteration-count: 1;
}

@keyframes snowfall {
  to {
    top: calc(100% + 1.5em);
    transform: translateX(-50%);
  }
}

@media (max-width: 820px) {
  .page-shell {
    --header-height: auto;
    grid-template:
      minmax(44px, auto)
      minmax(260px, 1fr)
      minmax(320px, auto)
      var(--footer-height)
      / 1fr;
  }

  .frame-header {
    align-items: center;
    gap: 10px;
    min-height: 44px;
    padding: 0 12px;
  }

  .about-text {
    line-height: 1.35;
    overflow: visible;
    text-overflow: clip;
    white-space: normal;
  }

  .about-text.is-visible,
  .about-text.is-fading {
    padding: 10px 0;
  }

  .frame-header,
  .frame-footer,
  .snow-pane,
  .stage {
    grid-column: 1;
  }

  .frame-header {
    grid-row: 1;
  }

  .snow-pane {
    grid-row: 2;
    border-right: 0;
    border-bottom: var(--line-width) solid var(--line-color);
  }

  .stage {
    grid-row: 3;
  }

  .frame-footer {
    grid-row: 4;
  }

  body[data-view="snow"] .page-shell,
  body[data-view="input"] .page-shell {
    grid-template:
      minmax(44px, auto)
      minmax(0, 1fr)
      var(--footer-height)
      / 1fr;
  }

  body[data-view="snow"] .snow-pane,
  body[data-view="input"] .stage {
    grid-row: 2;
    border-bottom: 0;
  }

  body[data-view="snow"] .frame-footer,
  body[data-view="input"] .frame-footer {
    grid-row: 3;
  }
}