:root {
  --bg: #121826;
  --panel: #1f2a44;
  --text: #f6f9ff;
  --accent: #6ec8ff;
  --good: #76e39b;
  --bad: #ff9aa2;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, #1e2e52, var(--bg));
  color: var(--text);
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
}

.container {
  width: min(760px, 92vw);
  margin: 0 auto;
  padding: 24px 0 40px;
}

.screen {
  display: none;
}

.screen.active {
  display: block;
}

.panel {
  background: var(--panel);
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

.status-bar {
  display: flex;
  gap: 16px;
  justify-content: space-between;
  margin-bottom: 16px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 10px;
  padding: 12px;
}

label {
  display: inline-block;
  margin-top: 12px;
  margin-right: 6px;
  font-weight: 700;
}

select,
input[type="file"] {
  margin-top: 8px;
  margin-bottom: 8px;
}

.settings-panel {
  margin-top: 14px;
  border: 1px solid rgba(110, 200, 255, 0.32);
  border-radius: 10px;
  padding: 10px 12px 12px;
}

.settings-panel legend {
  padding: 0 6px;
  color: #dff4ff;
  font-weight: 700;
}

.checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-right: 14px;
}

.checkbox-label input {
  margin: 0;
}

.voice-status {
  margin: 8px 0 0;
  color: #cfd8ef;
  font-size: 0.82rem;
}

select {
  border: 0;
  border-radius: 8px;
  padding: 9px 12px;
  font-size: 1rem;
}

button {
  margin-top: 10px;
  border: 0;
  border-radius: 8px;
  padding: 10px 14px;
  cursor: pointer;
  font-size: 1rem;
}

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

#start-btn,
#next-btn,
#retry-btn,
#load-wordbook-btn,
#reset-uploaded-data-btn,
#clear-retry-btn {
  background: var(--accent);
  color: #041022;
  font-weight: 700;
  margin-right: 8px;
}

.choices {
  margin-top: 16px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.choice-btn {
  background: #30476f;
  color: var(--text);
  text-align: left;
}

.choice-btn:hover {
  filter: brightness(1.12);
}

.encounter {
  color: #ffe39f;
  font-weight: 700;
}

.word {
  font-size: 2rem;
  margin: 8px 0 4px;
}

.hint {
  color: #cfd8ef;
  font-size: 0.9rem;
}

.message {
  min-height: 1.3em;
}

.data-source-status {
  margin: 10px 0 0;
  padding: 10px 12px;
  border: 1px solid rgba(110, 200, 255, 0.45);
  border-radius: 10px;
  background: rgba(110, 200, 255, 0.12);
  color: #e8f7ff;
  font-weight: 700;
}

.answer {
  color: #fcf2b5;
}

.feedbackOverlay {
  position: relative;
  margin-bottom: 14px;
  border-radius: 14px;
  padding: 14px 12px;
  background: rgba(255, 255, 255, 0.04);
  opacity: 0;
  transform: translateY(-6px);
  animation: fadeIn 220ms ease forwards;
  overflow: hidden;
}

.feedbackOverlay.correct {
  background: radial-gradient(circle at top, rgba(80, 255, 165, 0.42), rgba(18, 80, 45, 0.78));
  box-shadow: 0 0 24px rgba(84, 255, 180, 0.5);
}

.feedbackOverlay.incorrect {
  background: radial-gradient(circle at top, rgba(255, 108, 108, 0.35), rgba(100, 18, 18, 0.8));
  box-shadow: 0 0 24px rgba(255, 84, 84, 0.45);
  animation: fadeIn 220ms ease forwards, redFlash 500ms ease;
}

.feedbackOverlay.correct::after {
  content: "✦ ✧ ✦ ✧ ✦";
  position: absolute;
  top: 8px;
  right: 10px;
  font-size: 1rem;
  color: #ffe381;
  animation: sparkle 900ms ease-in-out infinite;
}

.feedbackCard { text-align: center; }
.feedbackPop .feedbackCard { animation: pop 300ms ease; }
.feedbackShake .feedbackCard { animation: shake 360ms ease; }

.feedbackIcon {
  font-size: clamp(2.2rem, 9vw, 3.6rem);
  line-height: 1;
}

.feedbackTitle {
  margin-top: 4px;
  font-size: clamp(1.8rem, 8vw, 2.8rem);
  font-weight: 900;
}

.feedbackSubText,
.feedbackAnswer,
.feedbackGold {
  margin-top: 6px;
  font-size: clamp(1rem, 4.1vw, 1.35rem);
  font-weight: 700;
}

.feedbackGold {
  color: #ffe381;
  text-shadow: 0 0 10px rgba(255, 227, 129, 0.8);
}

.feedbackAnswer { color: #fff1a5; }

@keyframes pop {
  0% { transform: scale(0.84); opacity: 0.5; }
  70% { transform: scale(1.06); opacity: 1; }
  100% { transform: scale(1); }
}
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-7px); }
  40% { transform: translateX(7px); }
  60% { transform: translateX(-5px); }
  80% { transform: translateX(5px); }
}
@keyframes redFlash {
  0% { filter: brightness(1); }
  35% { filter: brightness(1.18); }
  100% { filter: brightness(1); }
}
@keyframes sparkle {
  0%, 100% { opacity: 0.4; transform: translateY(0); }
  50% { opacity: 1; transform: translateY(-2px); }
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

#home-screen .panel button,
#home-screen .panel select {
  margin-top: 12px;
  margin-right: 0;
  width: 100%;
}

@media (min-width: 640px) {
  #home-screen .panel button,
  #home-screen .panel select {
    width: auto;
    margin-right: 10px;
  }
}


.study-app-link {
  margin: 12px 0 0;
  padding: 10px 12px;
  border: 1px solid rgba(118, 227, 155, 0.45);
  border-radius: 10px;
  background: rgba(118, 227, 155, 0.12);
  color: #e7ffef;
  font-weight: 700;
}

.study-app-link a {
  color: #9be7ff;
}

.study-app-action {
  margin: 12px 0;
}

.button-link {
  display: inline-block;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--accent);
  color: #041022;
  font-weight: 700;
  text-decoration: none;
}

.button-link:hover,
.button-link:focus-visible {
  filter: brightness(1.08);
}