:root {
  color-scheme: light;
  font-family: "Segoe UI", Arial, sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  --bar-height: 78px;
  --ink: #1d2927;
  --muted: #777f79;
  --paper: #f4f3ed;
  --line: #e3e4dc;
  --accent: #315b4b;
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
  overflow: hidden;
}

body {
  color: var(--ink);
  background: var(--paper);
}

.presentation-bar {
  position: relative;
  z-index: 10;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  height: var(--bar-height);
  padding: 0 clamp(16px, 4vw, 56px);
  border-bottom: 1px solid var(--line);
  background: rgba(250, 249, 245, 0.97);
}

.presentation-brand {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  gap: 11px;
  color: inherit;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  border: 1px solid #d6d9ce;
  border-radius: 50%;
  color: var(--accent);
  font-family: Georgia, serif;
  font-size: 19px;
}

.brand-copy {
  display: grid;
  gap: 3px;
}

.brand-copy strong {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.01em;
}

.brand-copy > span,
.switcher-label,
.presentation-note {
  color: var(--muted);
  font-size: 9px;
  font-weight: 650;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.switcher-wrap {
  display: grid;
  justify-items: center;
  gap: 7px;
}

.version-switcher {
  position: relative;
  display: grid;
  width: 204px;
  height: 36px;
  grid-template-columns: repeat(3, 1fr);
  padding: 3px;
  border: 1px solid #e3e4dc;
  border-radius: 999px;
  background: #edeee8;
  isolation: isolate;
}

.switcher-indicator {
  position: absolute;
  z-index: -1;
  top: 3px;
  bottom: 3px;
  left: 3px;
  width: calc((100% - 6px) / 3);
  border-radius: 999px;
  background: var(--accent);
  box-shadow: 0 2px 7px rgba(30, 54, 44, 0.18);
  transform: translateX(calc(var(--selected-index, 0) * 100%));
  transition: transform 420ms cubic-bezier(0.2, 0.75, 0.25, 1);
}

.version-button {
  min-width: 0;
  padding: 0;
  border: 0;
  border-radius: 999px;
  color: #68716c;
  background: transparent;
  font: inherit;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: color 220ms ease;
}

.version-button:hover {
  color: var(--ink);
}

.version-button.is-selected,
.version-button.is-selected:hover {
  color: #fff;
}

.version-button:focus-visible,
.presentation-brand:focus-visible {
  outline: 2px solid #6d927e;
  outline-offset: 3px;
}

.presentation-note {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  letter-spacing: 0.1em;
}

.presentation-note > span {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #91a58c;
  box-shadow: 0 0 0 3px #e7ebe2;
}

.concept-stage {
  position: relative;
  width: 100%;
  height: calc(100% - var(--bar-height));
  overflow: hidden;
  background: #fff;
}

.concept-stack {
  position: absolute;
  inset: 0;
  overflow: hidden;
  background: #fff;
}

.concept-frame {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  border: 0;
  background: #fff;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: scale(1.012);
  filter: blur(2px);
  transition:
    opacity 480ms cubic-bezier(0.22, 0.7, 0.25, 1),
    transform 560ms cubic-bezier(0.22, 0.7, 0.25, 1),
    filter 480ms ease,
    visibility 0s linear 560ms;
}

.concept-frame.is-active,
.concept-frame.is-exiting {
  visibility: visible;
  transition-delay: 0s;
}

.concept-frame.is-active {
  z-index: 2;
  opacity: 1;
  pointer-events: auto;
  transform: scale(1);
  filter: blur(0);
}

.concept-frame.is-exiting {
  z-index: 1;
  opacity: 0;
  pointer-events: none;
  transform: scale(0.994);
  filter: blur(2px);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 680px) {
  :root {
    --bar-height: 72px;
  }

  .presentation-bar {
    grid-template-columns: 1fr auto;
    padding: 0 14px;
  }

  .brand-mark {
    width: 34px;
    height: 34px;
  }

  .brand-copy > span {
    font-size: 8px;
  }

  .switcher-wrap {
    gap: 5px;
  }

  .switcher-label {
    font-size: 8px;
  }

  .version-switcher {
    width: 156px;
    height: 34px;
  }

  .presentation-note {
    display: none;
  }
}

@media (max-width: 360px) {
  .presentation-bar {
    padding: 0 10px;
  }

  .presentation-brand {
    gap: 7px;
  }

  .brand-copy strong {
    font-size: 14px;
  }

  .version-switcher {
    width: 138px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0ms !important;
  }
}