:root {
  --board-bg: #0b1f8f;
  --tile-bg: #ffffff;
  --tile-text: #16182b;
  --tile-blank: #1a7a3c;
  --tile-blank-edge: #0f5c29;
  --accent: #f2b705;
  --accent-dark: #c98f00;
  --bg: #061033;
  --text: #f4f6ff;
  --muted: #9aa4c7;
  --correct: #2e9e4f;
  --wrong: #c0392b;
  --key-bg: #1b2a5e;
  --key-bg-hover: #26397a;
  --key-used: #3a4570;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.site-header {
  padding: 1.5rem 1rem 0.5rem;
  text-align: center;
}

.site-header h1 {
  margin: 0;
  letter-spacing: 0.08em;
  font-size: 1.8rem;
  color: var(--accent);
  text-shadow: 0 2px 0 rgba(0, 0, 0, 0.4);
}

#app {
  width: 100%;
  max-width: 900px;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.screen[hidden] {
  display: none;
}

.screen {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

/* --- Create screen --- */

#create-screen {
  max-width: 560px;
  margin-top: 2rem;
}

#create-screen h2 {
  margin-bottom: 0;
}

.hint {
  color: var(--muted);
  text-align: center;
  margin-top: 0.25rem;
}

#create-form {
  width: 100%;
  display: flex;
  gap: 0.5rem;
}

#answer-input,
#solve-input,
#generated-link {
  flex: 1;
  padding: 0.6rem 0.8rem;
  border-radius: 6px;
  border: 1px solid var(--key-bg);
  background: #0f1a44;
  color: var(--text);
  font-size: 1rem;
}

#answer-input,
#solve-input {
  text-transform: uppercase;
}

#answer-input:focus,
#solve-input:focus {
  outline: 2px solid var(--accent);
}

button {
  cursor: pointer;
  border: none;
  border-radius: 6px;
  padding: 0.6rem 1rem;
  background: var(--accent);
  color: #1a1400;
  font-weight: 600;
  font-size: 1rem;
}

button:hover {
  background: var(--accent-dark);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.error {
  color: var(--wrong);
  font-weight: 600;
}

.result {
  width: 100%;
  background: #0f1a44;
  border-radius: 8px;
  padding: 1rem;
}

.link-row {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

/* --- Board --- */

.board {
  width: 100%;
  background: linear-gradient(180deg, #16359e 0%, var(--board-bg) 55%, #061a6e 100%);
  border: 6px solid var(--accent);
  box-shadow: inset 0 0 0 2px var(--accent-dark), 0 4px 14px rgba(0, 0, 0, 0.5);
  border-radius: 10px;
  padding: 0.75rem 0.4rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: clamp(0.15rem, 1vw, 0.35rem);
  min-height: 120px;
  overflow: hidden;
}

.board-row {
  display: flex;
  gap: clamp(0.1rem, 0.6vw, 0.25rem);
  justify-content: center;
}

.tile {
  width: clamp(0.85rem, 5.6vw, 2.1rem);
  height: clamp(1.1rem, 6.9vw, 2.6rem);
  background: var(--tile-blank);
  border: 1px solid var(--tile-blank-edge);
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Helvetica Condensed Bold', 'Helvetica Condensed', 'Arial Narrow', Helvetica, Arial, sans-serif;
  font-weight: 700;
  font-size: clamp(0.7rem, 4vw, 1.6rem);
  color: var(--tile-bg);
  transition: background 0.2s, color 0.2s, border-color 0.2s;
  perspective: 300px;
  flex-shrink: 0;
}

.tile.letter {
  background: var(--tile-bg);
  border-color: #c9ccd6;
  color: var(--tile-bg);
}

.tile.letter.revealed {
  color: var(--tile-text);
}

.tile.flip {
  animation: tile-flip 0.5s ease backwards;
}

@keyframes tile-flip {
  0% {
    transform: rotateY(0deg);
    background: var(--tile-bg);
    color: var(--tile-bg);
  }
  49% {
    background: var(--tile-bg);
    color: var(--tile-bg);
  }
  50% {
    transform: rotateY(90deg);
    background: var(--tile-bg);
    color: var(--tile-bg);
  }
  100% {
    transform: rotateY(0deg);
    background: var(--tile-bg);
    color: var(--tile-text);
  }
}

/* --- Phase banner --- */

.phase-banner {
  text-align: center;
  font-size: 1rem;
  color: var(--muted);
  min-height: 1.4em;
}

/* --- Pick panel --- */

.pick-panel {
  text-align: center;
}

/* --- Solve panel --- */

.solve-panel {
  width: 100%;
  max-width: 500px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

#solve-form {
  width: 100%;
  display: flex;
  gap: 0.5rem;
}

.feedback {
  font-weight: 600;
}

.feedback.correct {
  color: var(--correct);
}

.feedback.wrong {
  color: var(--wrong);
}

/* --- Keyboard --- */

.keyboard {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.35rem;
  max-width: 600px;
}

.key {
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 6px;
  background: var(--key-bg);
  color: var(--text);
  font-weight: 700;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}

.key:hover:not(:disabled) {
  background: var(--key-bg-hover);
}

.key:disabled {
  background: var(--key-used);
  color: var(--muted);
  opacity: 1;
  cursor: not-allowed;
}

.key.selected {
  background: var(--accent);
  color: #1a1400;
}

/* --- Controls --- */

.controls {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.controls button {
  background: var(--key-bg);
  color: var(--text);
  font-weight: 500;
}

.controls button:hover {
  background: var(--key-bg-hover);
}

@media (max-width: 480px) {
  .key {
    width: 2rem;
    height: 2rem;
    font-size: 0.95rem;
  }
}