:root {
  --bg: #ffffff;
  --panel: #fff;
  --ink: #111111;
  --line: #d6d6d6;
  --shadow: 0 16px 40px rgba(0, 0, 0, 0.12);
  --app-font:
    "SassoonPrimaryEmbedded",
    "Sassoon Primary",
    "Sassoon Primary Regular",
    Arial,
    Helvetica,
    sans-serif;
}

@font-face {
  font-family: "SassoonPrimaryEmbedded";
  font-weight: 400;
  src: url("./fonts/SassoonPrimary-Regular.ttf") format("opentype");
  font-display: block;
}

* {
  box-sizing: border-box;
  font-family: var(--app-font);
}

html,
body,
#app {
  height: 100%;
}

body {
  margin: 0;
  font-family: var(--app-font);
  background: var(--bg);
  color: var(--ink);
}

#app {
  position: relative;
  overflow: hidden;
}

.view {
  position: absolute;
  inset: 0;
  display: none;
}

.view.active {
  display: block;
}

#setup-view {
  background: #fff;
  display: none;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

#setup-view.active {
  display: flex;
}

h1 {
  margin: 0;
  font-size: clamp(1.4rem, 2.5vw, 2rem);
}

p {
  margin: 0;
}

.line-label {
  font-weight: 600;
}

.line-count-row {
  display: flex;
  gap: 0.75rem;
  align-items: center;
}

#line-count {
  width: 6.5rem;
  height: 2.5rem;
  border-radius: 0.5rem;
  border: 1px solid #999;
  font-size: 1rem;
  padding: 0 0.7rem;
}

.book-library {
  display: grid;
  grid-template-columns: minmax(7rem, auto) minmax(0, 1fr);
  gap: 0.5rem 0.75rem;
  align-items: center;
}

#book-title,
#saved-books {
  width: 100%;
  min-width: 0;
  height: 2.5rem;
  border: 1px solid #999;
  border-radius: 0.5rem;
  padding: 0 0.7rem;
  font-size: 1rem;
  font-family: inherit;
  background: #ffffff;
  color: #111111;
}

.saved-books-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto auto;
  gap: 0.5rem;
  align-items: center;
}

.btn-primary {
  border: 0;
  height: 2.5rem;
  border-radius: 0.7rem;
  cursor: pointer;
  background: #111;
  color: #fff;
  font-weight: 600;
  font-size: 1rem;
}

.btn-secondary {
  border: 1px solid #2f2f2f;
  height: 2.5rem;
  border-radius: 0.7rem;
  cursor: pointer;
  background: #fff;
  color: #111;
  font-weight: 600;
  font-size: 1rem;
}

.setup-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.start-btn {
  width: 12rem;
}

#save-status {
  min-height: 1.2rem;
  font-size: 0.9rem;
  color: #2a2a2a;
}

.line-form {
  margin-top: 0.35rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  overflow: auto;
  max-height: calc(100vh - 240px);
  padding-right: 0.2rem;
}

.line-input-wrap {
  display: grid;
  grid-template-columns: 4rem minmax(0, 1fr) 2.7rem;
  gap: 0.55rem;
  align-items: start;
}

.line-input-wrap label {
  padding-top: 0.65rem;
  font-weight: 600;
}

.line-input-wrap textarea {
  width: 100%;
  min-height: 4.6rem;
  border: 1px solid var(--line);
  border-radius: 0.6rem;
  padding: 0.65rem;
  resize: vertical;
  font-size: 1rem;
  font-family: inherit;
}

.line-start-btn {
  width: 2.7rem;
  height: 2.7rem;
  margin-top: 0.35rem;
  border: 1px solid #2f2f2f;
  border-radius: 999px;
  cursor: pointer;
  background: #ffffff;
  color: #111111;
  font-size: 1rem;
  line-height: 1;
}

/* Reader view */
#reader-view {
  background: #ffffff;
  color: var(--ink);
  --reader-letter-stroke-color: #000000;
  transition: background 0.15s ease;
}

#reader-view.inverted {
  background: #000000;
  --reader-letter-stroke-color: #ffffff;
}

.toolbar-btn {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 3;
  border: 0;
  border-radius: 0;
  width: 3rem;
  height: 3rem;
  padding: 0;
  font-size: 0;
  background: transparent;
  color: transparent;
  cursor: pointer;
  opacity: 0;
}

#reader-view.show-back .toolbar-btn {
  pointer-events: auto;
  background: transparent;
  color: transparent;
  opacity: 0;
}

#palette {
  position: fixed;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 5;
  display: flex;
  flex-direction: column;
  gap: clamp(0.18rem, 0.45vh, 0.34rem);
  align-items: center;
  background: #ffffffcc;
  border-radius: 0.75rem;
  padding: clamp(0.22rem, 0.7vh, 0.42rem);
  border: 1px solid #ddd;
  box-shadow: var(--shadow);
  background: #ffffff;
}

.palette-button {
  width: clamp(1.8rem, 4vh, 2.35rem);
  height: clamp(1.8rem, 4vh, 2.35rem);
  border: 2px solid #222;
  border-radius: 999px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0;
  color: #fff;
  text-transform: capitalize;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
}

.palette-button[data-color="rainbow"] {
  color: #111;
  font-size: 0;
}

.palette-button[data-color="theme-toggle"] {
  font-size: 1rem;
  background: #ffffff;
  color: #111111;
  border-color: #111111;
}

#reader-view.inverted .palette-button[data-color="theme-toggle"] {
  background: #111111;
  color: #ffffff;
  border-color: #ffffff;
}

.palette-button:focus-visible,
.palette-button:hover {
  transform: scale(1.05);
}

.palette-button.active {
  outline: 4px solid #000;
  outline-offset: 2px;
}

#word-area {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-rows: 1fr auto;
}

#word-display {
  position: relative;
  z-index: 4;
  display: flex;
  align-items: center;
  justify-content: center;
  column-gap: var(--word-letter-gap);
  padding: 1rem 1.25rem 0.5rem;
  text-align: center;
  pointer-events: none;
  --reader-word-font: var(--app-font);
  font-family: var(--reader-word-font);
  --word-font-size: 14rem;
  --word-letter-gap: clamp(0.25rem, calc(var(--word-font-size) * 0.035), 3rem);
}

.letter-wrap {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: clamp(0.15rem, calc(var(--word-font-size) * 0.01), 0.75rem);
  line-height: 1.12;
  position: relative;
  z-index: 0;
  pointer-events: auto;
  --letter-outline-width: 0.03em;
  --letter-outline-neg: -0.03em;
  --letter-outline-half: 0.018em;
  --letter-outline-half-neg: -0.018em;
}

.letter-wrap.highlighted::before {
  content: "";
  position: absolute;
  top: -100vh;
  bottom: -100vh;
  left: calc(var(--word-letter-gap) * -0.5);
  right: calc(var(--word-letter-gap) * -0.5);
  z-index: 0;
  background: rgba(132, 181, 246, 0.62);
  pointer-events: none;
}

.letter-svg {
  display: block;
  overflow: visible;
  cursor: pointer;
  flex: 0 0 auto;
  position: relative;
  z-index: 1;
}

.letter {
  display: inline-block;
  line-height: 1.12;
  font-size: var(--word-font-size);
  font-family: inherit;
  font-weight: inherit;
  padding: 0 0 0.22em;
  margin-bottom: -0.22em;
  cursor: pointer;
  border-radius: 0.15rem;
  border: 2px solid transparent;
  -webkit-text-stroke: 0 transparent;
  user-select: none;
}

.letter-outline {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 0;
  color: var(--reader-letter-stroke-color);
  pointer-events: none;
  text-shadow:
    var(--letter-outline-neg) 0 0 var(--reader-letter-stroke-color),
    var(--letter-outline-width) 0 0 var(--reader-letter-stroke-color),
    0 var(--letter-outline-neg) 0 var(--reader-letter-stroke-color),
    0 var(--letter-outline-width) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-neg) var(--letter-outline-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-width) var(--letter-outline-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-neg) var(--letter-outline-width) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-width) var(--letter-outline-width) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-half-neg) var(--letter-outline-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-half) var(--letter-outline-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-half-neg) var(--letter-outline-width) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-half) var(--letter-outline-width) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-neg) var(--letter-outline-half-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-width) var(--letter-outline-half-neg) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-neg) var(--letter-outline-half) 0 var(--reader-letter-stroke-color),
    var(--letter-outline-width) var(--letter-outline-half) 0 var(--reader-letter-stroke-color);
}

.letter-fill {
  position: relative;
  z-index: 1;
  text-shadow: none;
}

.letter-highlight-toggle {
  width: 80%;
  min-width: 1.2rem;
  height: clamp(1.5rem, calc(var(--word-font-size) * 0.08), 4.5rem);
  margin-top: 0;
  border: 0;
  padding: 0;
  background: transparent;
  opacity: 0;
  cursor: pointer;
  position: relative;
  z-index: 2;
}

.letter-highlight-toggle:focus-visible {
  opacity: 1;
  background: #ffe66d;
  border-radius: 999px;
  outline: 3px solid #111111;
  outline-offset: 2px;
}

.arrow-nav {
  position: fixed;
  top: 0;
  bottom: 0;
  width: 20vw;
  max-width: 170px;
  min-width: 120px;
  border: 0;
  background: transparent;
  opacity: 0.06;
  transition: opacity 0.2s ease;
  z-index: 2;
}

.arrow-nav span {
  display: block;
  color: #111;
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  pointer-events: none;
  font-size: clamp(2.5rem, 7vw, 4.5rem);
  user-select: none;
}

.arrow-prev {
  left: 0;
}

.arrow-prev span {
  left: 14px;
}

.arrow-next {
  right: 0;
}

.arrow-next span {
  right: 14px;
}

.arrow-prev:hover,
.arrow-next:hover,
.arrow-prev:focus-visible,
.arrow-next:focus-visible {
  opacity: 0.36;
  outline: none;
}

@media (max-width: 800px) {
  .book-library {
    grid-template-columns: 1fr;
  }

  .saved-books-row {
    grid-template-columns: 1fr 1fr 1fr;
  }

  .line-input-wrap {
    grid-template-columns: 3.2rem minmax(0, 1fr) 2.5rem;
  }

  #palette {
    right: 0.7rem;
    top: auto;
    bottom: 0.9rem;
    transform: none;
    flex-direction: row;
    flex-wrap: wrap;
    max-width: 214px;
    justify-content: center;
  }

  .palette-button {
    width: clamp(1.75rem, 8vw, 2.15rem);
    height: clamp(1.75rem, 8vw, 2.15rem);
    font-size: 0;
  }

  #word-display {
    padding: 0 2.1rem 0.7rem 2.1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition-duration: 0.01ms !important;
  }
}