* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: linear-gradient(135deg, #0B2027 0%, #122C3C 40%, #1B3A4B 100%);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  min-height: 88vh;
  overflow-y: auto;
}

.writing-wrapper {
  width: 96vw;
  margin: 12vh auto 4vh;
  display: flex;
  flex-direction: column;
  gap: 1vh;
  height: 78vh;
  overflow: hidden;
}

.writing-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2vw;
}

.nav-center {
  display: flex;
  align-items: center;
  gap: 2vw;
  justify-content: center;
}

.index-display {
  background: rgba(0, 217, 232, 0.08);
  border: 0.2vw solid var(--input-border);
  border-radius: 1.5vw;
  padding: 1vh 2vw;
  font-size: 3vw;
  font-weight: 700;
  color: var(--accent-primary);
  text-align: center;
  min-width: 20vw;
}

.jump-control {
  display: flex;
  align-items: center;
  gap: 1vw;
  background: rgba(0, 217, 232, 0.08);
  border: 0.2vw solid var(--input-border);
  border-radius: 1.5vw;
  padding: 0.3vh 1vw;
}

.jump-btn {
  background: var(--btn-primary-bg);
  border: none;
  color: var(--btn-primary-text);
  cursor: pointer;
  padding: 0.8vh 3vw;
  border-radius: 1.2vw;
  font-size: 3.2vw;
  font-weight: 700;
  transition: all 0.3s ease;
}

.jump-btn:hover { background: var(--btn-primary-hover); transform: translateY(-0.2vh); }

.jump-input {
  width: 11vw;
  background: transparent;
  border: none;
  color: var(--accent-primary);
  padding: 0.5vh 1vw;
  font-size: 3.2vw;
  font-weight: 600;
  text-align: center;
  outline: none;
}

.jump-input::placeholder { color: var(--input-placeholder); }
.jump-input::-webkit-outer-spin-button,
.jump-input::-webkit-inner-spin-button { -webkit-appearance: none; }
.jump-input[type=number] { -moz-appearance: textfield; }

.save-btn {
  background: var(--btn-secondary-bg);
  border: 0.2vw solid var(--btn-secondary-border);
  border-radius: 1.5vw;
  padding: 1vh 1.5vw;
  color: var(--accent-primary);
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 8vw;
  min-height: 5vh;
}

.save-btn:hover { background: var(--btn-secondary-hover); border-color: var(--accent-primary); }
.save-icon { width: 3.5vw; height: 3.5vw; fill: currentColor; }

.writing-card {
  flex: 1;
  background: var(--bg-glass);
  border: 0.2vw solid var(--card-border);
  border-radius: 2.5vw;
  box-shadow: var(--card-shadow), inset 0 0.1vh 0 rgba(255,255,255,0.05);
  backdrop-filter: blur(1.2vw);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2vh 5vw 3vh;
  gap: 2vh;
  min-height: 0;
  transition: border-color 0.4s ease, box-shadow 0.4s ease;
}

.writing-card.card-correct {
  border-color: rgba(16, 185, 129, 0.6);
  box-shadow: var(--card-shadow), 0 0 4vw rgba(16, 185, 129, 0.2);
}

.writing-card.card-wrong {
  border-color: rgba(239, 68, 68, 0.5);
  box-shadow: var(--card-shadow), 0 0 4vw rgba(239, 68, 68, 0.15);
  animation: shake 0.4s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%       { transform: translateX(-1.5vw); }
  40%       { transform: translateX(1.5vw); }
  60%       { transform: translateX(-1vw); }
  80%       { transform: translateX(1vw); }
}

.nav-btn {
  background: var(--btn-secondary-bg);
  border: 0.2vw solid var(--btn-secondary-border);
  border-radius: 1.5vw;
  padding: 0.7vh 4vw;
  font-size: 4vw;
  font-weight: 700;
  color: var(--accent-primary);
  cursor: pointer;
  transition: all 0.3s ease;
}

.nav-btn:hover {
  background: var(--btn-secondary-hover);
  border-color: var(--accent-primary);
  transform: translateY(-0.3vh);
  box-shadow: 0 0.5vh 1.5vw rgba(0, 217, 232, 0.25);
}

.nav-btn:active { transform: translateY(0); }

.nav-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.listen-btn {
  display: inline-flex;
  align-items: center;
  gap: 2.5vw;
  background: var(--btn-primary-bg);
  border: none;
  border-radius: 4vw;
  padding: 2.5vh 10vw;
  font-size: 7vw;
  font-weight: 800;
  color: var(--btn-primary-text);
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: var(--btn-primary-shadow);
}

.listen-btn:hover {
  background: var(--btn-primary-hover);
  transform: translateY(-0.5vh) scale(1.02);
  box-shadow: 0 1.5vh 4vw rgba(0, 217, 232, 0.5);
}

.listen-btn:active { transform: scale(0.98); }

.listen-btn.playing {
  background: linear-gradient(135deg, #10B981 0%, #059669 100%);
  box-shadow: 0 0.8vh 3vw rgba(16, 185, 129, 0.6);
  animation: pulse 1s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0.8vh 3vw rgba(16, 185, 129, 0.5); }
  50%       { box-shadow: 0 0.8vh 5vw rgba(16, 185, 129, 0.85); }
}

.answer-reveal {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.8vh;
  animation: fadeUp 0.35s ease-out;
}

.answer-reveal.hidden { display: none; }

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(1.5vh); }
  to   { opacity: 1; transform: translateY(0); }
}

.answer-divider {
  width: 40%;
  height: 0.2vw;
  background: var(--border-subtle);
  border-radius: 1vw;
  margin-bottom: 0.3vh;
}

.correct-label {
  font-size: 3vw;
  color: var(--text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.2vw;
}

.correct-text {
  font-size: 5vw;
  font-weight: 800;
  color: var(--accent-primary);
  text-shadow: 0 0 3vw rgba(0, 217, 232, 0.4);
  text-align: center;
  line-height: 1.2;
}

.phonetic-text {
  font-size: 4vw;
  color: rgba(0, 217, 232, 0.55);
  font-weight: 400;
}

.writing-input {
  display: grid;
  grid-template-columns: 1fr 0.5fr;
  grid-template-rows: auto auto;
  gap: 0.7vh 1vw;
  width: 100%;
}

.writing-input #GotoBtn       { grid-column: 1; grid-row: 1; }
.writing-input #ShowAnswerBtn { grid-column: 2; grid-row: 1; }

.writing-input input {
  grid-column: 1;
  grid-row: 2;
  width: 100%;
  height: 6vh;
  border-radius: 2vw;
  background: var(--input-bg);
  border: 0.2vw solid var(--input-border);
  padding: 0 4vw;
  font-size: 3.8vw;
  color: var(--input-text);
  outline: none;
  transition: all 0.3s ease;
}

.writing-input #SendBtn { grid-column: 2; grid-row: 2; }

.writing-input input:focus {
  background: rgba(0, 217, 232, 0.12);
  border-color: var(--input-border-focus);
  box-shadow: 0 0 0 0.5vw rgba(0, 217, 232, 0.1);
}

.writing-input input::placeholder { color: var(--input-placeholder); }

.writing-input input.input-correct {
  border-color: rgba(16, 185, 129, 0.7);
  background: rgba(16, 185, 129, 0.08);
}

.writing-input input.input-wrong {
  border-color: rgba(239, 68, 68, 0.6);
  background: rgba(239, 68, 68, 0.06);
}

.control-btn {
  padding: 1.5vh 4vw;
  border: none;
  border-radius: 2vw;
  font-size: 3.5vw;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  width: 100%;
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  box-shadow: var(--btn-primary-shadow);
}

.btn-primary:hover { background: var(--btn-primary-hover); transform: translateY(-0.3vh); }

.btn-secondary {
  background: var(--btn-secondary-bg);
  color: var(--btn-secondary-text);
  border: 0.2vw solid var(--btn-secondary-border);
}

.btn-secondary:hover { background: var(--btn-secondary-hover); border-color: var(--accent-primary); transform: translateY(-0.3vh); }

#DisclaimerContainer {
  position: fixed;
  top: 8vh;
  left: 0;
  width: 100vw;
  padding: 0.5vh 0;
  backdrop-filter: blur(2vw);
  border-bottom: 0.2vw solid var(--card-border);
  z-index: 100;
}

#DisclaimerText {
  font-size: 1.75vw;
  color: var(--text-secondary);
  text-align: center;
  opacity: 0.7;
}

/* TABLET */
@media (min-width: 768px) {
  .writing-wrapper { width: 92vw; margin: 14vh auto 2vh; gap: 1vh; height: 78vh; }

  .writing-nav { gap: 1.5vw; }
  .nav-center { gap: 1.5vw; }
  .index-display { font-size: 1.6vw; padding: 0.9vh 2vw; min-width: 10vw; border-radius: 0.8vw; border-width: 0.15vw; }
  .jump-control { gap: 0.8vw; padding: 0.6vh 1.2vw; border-radius: 0.8vw; border-width: 0.15vw; }
  .jump-btn { padding: 0.8vh 1.8vw; font-size: 1.4vw; border-radius: 0.7vw; }
  .jump-input { width: 7vw; font-size: 1.4vw; }
  .save-btn { min-width: 4.5vw; min-height: 4.5vw; border-radius: 0.8vw; border-width: 0.15vw; padding: 0.9vh 1.5vw; }
  .save-icon { width: 2vw; height: 2vw; }

  .writing-card { border-radius: 1.5vw; border-width: 0.15vw; padding: 1.5vh 3vw 2.5vh; }
  .nav-btn { padding: 1vh 2.5vw; font-size: 1.6vw; border-radius: 0.8vw; border-width: 0.15vw; }
  .listen-btn { font-size: 3vw; padding: 2vh 6vw; border-radius: 2vw; gap: 1.2vw; }
  .correct-label { font-size: 1.3vw; }
  .correct-text { font-size: 4vw; }
  .phonetic-text { font-size: 3vw; }
  .answer-divider { height: 0.12vw; }

  .writing-input {
    grid-template-columns: auto auto 1fr auto;
    grid-template-rows: auto;
    gap: 1.5vw;
  }
  .writing-input #GotoBtn       { grid-column: 1; grid-row: 1; }
  .writing-input #ShowAnswerBtn { grid-column: 2; grid-row: 1; }
  .writing-input input { grid-column: 3; grid-row: 1; height: 6vh; border-radius: 1.2vw; border-width: 0.15vw; padding: 0 2.5vw; font-size: 1.6vw; }
  .writing-input #SendBtn { grid-column: 4; grid-row: 1; }

  .control-btn { padding: 1.5vh 3vw; border-radius: 1.2vw; font-size: 1.5vw; width: auto; }
  .btn-secondary { border-width: 0.15vw; }

  #DisclaimerContainer { top: 10vh; border-width: 0.1vw; }
  #DisclaimerText { font-size: 1.5vw; }
}

/* DESKTOP */
@media (min-width: 1024px), (orientation: landscape) {
  body { min-height: 100vh; overflow: hidden; }
  .writing-wrapper { width: 85vw; margin: 12vh auto 0; gap: 1.8vh; overflow: hidden; }

  .writing-nav { gap: 1vw; }
  .nav-center { gap: 1vw; }
  .index-display { font-size: 1.2vw; padding: 0.8vh 1.5vw; min-width: 8vw; border-radius: 0.6vw; border-width: 0.1vw; }
  .jump-control { gap: 0.6vw; padding: 0.5vh 1vw; border-radius: 0.6vw; border-width: 0.1vw; }
  .jump-btn { padding: 0.7vh 1.5vw; font-size: 1.1vw; border-radius: 0.5vw; }
  .jump-input { width: 5vw; font-size: 1.1vw; }
  .save-btn { min-width: 2.5vw; min-height: 2.5vw; padding: 0vh 1.2vw; border-radius: 0.6vw; border-width: 0.1vw; }
  .save-icon { width: 1.3vw; height: 1.3vw; }

  .writing-card { border-radius: 1vw; border-width: 0.1vw; padding: 1.2vh 2.5vw 2vh; }
  .nav-btn { padding: 0.9vh 2vw; font-size: 1.2vw; border-radius: 0.6vw; border-width: 0.1vw; }
  .listen-btn { font-size: 2vw; padding: 1.8vh 5vw; border-radius: 1.2vw; gap: 0.8vw; }
  .correct-label { font-size: 0.85vw; letter-spacing: 0.12vw; }
  .correct-text { font-size: 1.8vw; }
  .phonetic-text { font-size: 1.2vw; }
  .answer-divider { height: 0.08vw; }

  .writing-input { gap: 1.2vw; }
  .writing-input input { height: 5.5vh; border-radius: 1vw; border-width: 0.1vw; padding: 0 2vw; font-size: 1.3vw; }
  .control-btn { padding: 1.3vh 2.5vw; border-radius: 1vw; font-size: 1.2vw; }
  .btn-secondary { border-width: 0.1vw; }

  #DisclaimerContainer { top: 96.5vh; border-bottom: none; border-width: 0.08vw; }
  #DisclaimerText { font-size: 0.9vw; }
}

@media (orientation: landscape) and (hover: none) and (pointer: coarse) {
  html, body { overflow: auto; }
}