* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

[hidden] { display: none !important; }

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

body {
  display: flex;
  flex-direction: column;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
  background: linear-gradient(160deg, #5b3cf4, #9b3cf4);
  color: #fff;
  overscroll-behavior: none;
  user-select: none;
  -webkit-user-select: none;
}

button {
  border: none;
  background: none;
  color: #fff;
  font-family: inherit;
  cursor: pointer;
}

#app-header {
  flex-shrink: 0;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: calc(1.75rem + env(safe-area-inset-top)) 3.5rem 0.5rem;
}

#app-title {
  margin: 0;
  font-size: clamp(1.4rem, 8vw, 2.2rem);
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-align: center;
  line-height: 1.15;
  opacity: 0.92;
}

.install-banner {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 1rem;
  background: rgba(255, 255, 255, 0.12);
  font-size: 0.9rem;
  cursor: default;
}

.install-banner span {
  flex: 1;
}

#install-btn {
  background: rgba(255, 255, 255, 0.25);
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.5rem 0.9rem;
  border-radius: 0.5rem;
  white-space: nowrap;
}

#install-btn:active {
  background: rgba(255, 255, 255, 0.4);
}

#install-dismiss {
  opacity: 0.7;
  font-size: 1.2rem;
  line-height: 1;
  padding: 0.25rem;
}

#screen {
  flex: 1;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 1.5rem;
  text-align: center;
}

.view {
  cursor: pointer;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.header-btn {
  position: absolute;
  top: calc(1.5rem + env(safe-area-inset-top));
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  font-size: 1.4rem;
  line-height: 1;
}

.header-btn:active {
  background: rgba(255, 255, 255, 0.28);
}

#rules-toggle {
  left: 0.75rem;
  font-weight: 700;
}

#settings-toggle {
  right: 0.75rem;
}

.letter-label {
  font-size: clamp(1rem, 4vw, 1.3rem);
  opacity: 0.75;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-top: 1rem;
}

.letter {
  font-size: clamp(4rem, 22vw, 9rem);
  font-weight: 800;
  line-height: 1;
}

.word {
  font-size: clamp(2rem, 9vw, 4rem);
  font-weight: 700;
  word-break: break-word;
}

#next {
  background: rgba(255, 255, 255, 0.15);
  font-size: 1.3rem;
  font-weight: 600;
  padding: 1.25rem;
  padding-bottom: calc(1.25rem + env(safe-area-inset-bottom));
}

#next:active {
  background: rgba(255, 255, 255, 0.28);
}

.choice-view {
  gap: 0.75rem;
}

#single-view,
.choice-card {
  position: relative;
  overflow: hidden;
  width: 100%;
  max-width: 28rem;
  border: 2px solid rgba(255, 255, 255, 0.25);
  border-radius: 1rem;
  background: rgba(255, 255, 255, 0.08);
  padding: 1.5rem 1rem;
}

.choice-or {
  font-size: 1rem;
  font-weight: 600;
  opacity: 0.75;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.choice-word {
  font-size: clamp(1.5rem, 6vw, 2.5rem);
}

.choice-letter {
  font-size: clamp(2.5rem, 12vw, 5rem);
}

@keyframes card-enter {
  from {
    opacity: 0;
    transform: translateX(28px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

#single-view.enter,
.choice-card.enter {
  animation: card-enter 260ms cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

#choice-1.enter {
  animation-delay: 80ms;
}

@media (prefers-reduced-motion: reduce) {
  #single-view.enter,
  .choice-card.enter {
    animation: none;
  }
}

.word,
.letter,
.letter-label {
  transition: filter 0.15s ease-out;
}

.blurred .word,
.blurred .letter,
.blurred .letter-label {
  filter: blur(18px);
}

.reveal-hint {
  display: none;
  margin-top: 0.75rem;
  font-size: 1rem;
  font-weight: 600;
  opacity: 0.85;
}

.blurred .reveal-hint {
  display: block;
}

.reveal-timer {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 4px;
  background: rgba(255, 255, 255, 0.6);
  transform-origin: left center;
  opacity: 0;
}

.conceal .reveal-timer {
  opacity: 1;
}

.conceal .blurred .reveal-timer {
  opacity: 0;
}

.settings-overlay {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.settings-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
}

.settings-panel {
  position: relative;
  width: 100%;
  max-width: 24rem;
  background: #3d2596;
  color: #fff;
  border-radius: 1rem;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  cursor: default;
}

.settings-panel h2 {
  margin: 0;
  font-size: 1.2rem;
}

.settings-row {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 1rem;
}

.settings-row select {
  font-size: 1rem;
  padding: 0.5rem;
  border-radius: 0.5rem;
  border: none;
}

.settings-fieldset {
  border: none;
  padding: 0;
  margin: 0;
}

.settings-fieldset legend {
  padding: 0;
  margin-bottom: 0.5rem;
}

.settings-radio {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1rem;
}

.settings-checkbox {
  flex-direction: row;
  align-items: center;
}

.panel-close {
  background: rgba(255, 255, 255, 0.2);
  font-size: 1.1rem;
  font-weight: 600;
  padding: 0.75rem;
  border-radius: 0.5rem;
}

.panel-close:active {
  background: rgba(255, 255, 255, 0.35);
}

.settings-version {
  text-align: center;
  font-size: 0.75rem;
  opacity: 0.4;
}

.rules-panel {
  max-height: calc(100vh - 3rem);
  overflow-y: auto;
}

.rules-text {
  font-size: 0.95rem;
  line-height: 1.5;
}

.rules-text p {
  margin: 0 0 0.75rem;
}

.rules-text h3 {
  margin: 1rem 0 0.5rem;
  font-size: 1rem;
}

.rules-text ul {
  margin: 0;
  padding-left: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}