/* ========================================================
   Plataforma Experimental de Discriminación Condicionada
   Paleta pastel y estilo académico. Diseñada primero para móvil.
   ======================================================== */

:root {
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  --bg-primary: #f2f5f3;
  --bg-surface: #ffffff;
  --bg-surface-elevated: #f7faf8;
  --bg-input: #ffffff;

  --text-primary: #1f3026;
  --text-secondary: #4a6356;
  --text-muted: #748c80;

  --border-subtle: #d6e2db;
  --border-focus: #4a7c64;

  --accent-primary: #4a7c64;
  --accent-primary-hover: #3a6350;
  --accent-pastel: #eaf3ed;
  --accent-pastel-text: #284e3c;

  --feedback-correct: #329362;
  --feedback-correct-bg: #ebf7f0;
  --feedback-correct-glow: rgba(50, 147, 98, 0.28);
  --feedback-incorrect: #c24e4e;
  --feedback-incorrect-bg: #fdf1f1;
  --feedback-incorrect-glow: rgba(194, 78, 78, 0.28);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 18px;

  --shadow-sm: 0 1px 3px rgba(31, 48, 38, 0.04);
  --shadow-md: 0 4px 14px rgba(31, 48, 38, 0.06);
  --shadow-lg: 0 10px 28px rgba(31, 48, 38, 0.08);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-font-smoothing: antialiased;
}

[hidden] {
  display: none !important;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

/* ========================================================
   PANTALLA DE CARGA
   ======================================================== */
.app-splash {
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at center, #ffffff 0%, #edf4ef 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.app-splash.fade-out {
  opacity: 0;
  transform: scale(1.03);
  pointer-events: none;
}

.splash-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 38px 32px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: 0 16px 40px rgba(31, 48, 38, 0.08);
  max-width: 440px;
  width: calc(100% - 32px);
  animation: splashCardIn 0.55s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes splashCardIn {
  from { opacity: 0; transform: translateY(16px) scale(0.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.splash-pulse {
  position: relative;
  width: 68px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.splash-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid var(--accent-primary);
  opacity: 0.35;
  animation: pulseRipple 1.8s ease-out infinite;
}

@keyframes pulseRipple {
  0% { transform: scale(0.85); opacity: 0.75; }
  100% { transform: scale(1.45); opacity: 0; }
}

.splash-core {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--accent-pastel);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 14px rgba(74, 124, 100, 0.2);
}

.splash-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 14px;
  font-size: 0.74rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: 999px;
  background: var(--accent-pastel);
  color: var(--accent-pastel-text);
  border: 1px solid var(--border-subtle);
  margin-bottom: 12px;
}

.splash-title {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 6px;
}

.splash-subtitle {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 22px;
}

.splash-track {
  width: 190px;
  height: 4px;
  background: var(--border-subtle);
  border-radius: 999px;
  overflow: hidden;
}

.splash-bar {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--accent-primary), #68ad8c);
  border-radius: 999px;
  animation: fillProgress 0.9s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes fillProgress {
  0% { width: 0%; }
  60% { width: 75%; }
  100% { width: 100%; }
}

.btn-splash-enter {
  margin-top: 6px;
  padding: 14px 34px;
  background: var(--accent-primary);
  color: #ffffff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 4px 16px rgba(74, 124, 100, 0.28);
  animation: enterBtnIn 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-splash-enter:active {
  background: var(--accent-primary-hover);
}

@keyframes enterBtnIn {
  from { opacity: 0; transform: translateY(10px) scale(0.95); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* ========================================================
   CONTENEDOR PRINCIPAL
   ======================================================== */
.main-content {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  padding-left: max(16px, env(safe-area-inset-left));
  padding-right: max(16px, env(safe-area-inset-right));
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ========================================================
   BIENVENIDA Y FORMULARIO
   ======================================================== */
.welcome-container {
  width: 100%;
  max-width: 760px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  animation: fadeIn 0.3s ease-out;
}

.sound-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: var(--shadow-sm);
}

.sound-card-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--accent-pastel);
  color: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.sound-card-body {
  font-size: 0.86rem;
  line-height: 1.45;
}

.sound-card-title {
  font-weight: 700;
  margin-right: 4px;
}

.sound-card-desc {
  color: var(--text-secondary);
}

.glass-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 760px;
  padding: 38px 42px;
  animation: fadeIn 0.3s ease-out;
}

.instruction-lead {
  font-size: 1.05rem;
  font-weight: 500;
  line-height: 1.6;
  background: #edf5f0;
  border: 1px solid #d4e5dc;
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin-bottom: 24px;
}

.step-badge {
  display: inline-flex;
  padding: 4px 12px;
  font-size: 0.74rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: 999px;
  background: var(--accent-pastel);
  color: var(--accent-pastel-text);
  border: 1px solid var(--border-subtle);
  margin-bottom: 20px;
}

.duration-card {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 16px;
}

.duration-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.duration-value {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.glass-card .instruction-lead {
  margin-bottom: 16px;
}

.glass-card .sound-card {
  margin-bottom: 24px;
  box-shadow: none;
  background: var(--bg-surface-elevated);
}

.btn-link {
  display: block;
  margin: 14px auto 0;
  padding: 8px 12px;
  background: none;
  border: none;
  font: inherit;
  font-size: 0.9rem;
  color: var(--text-secondary);
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 18px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.form-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-label .required {
  color: var(--feedback-incorrect);
  margin-left: 2px;
}

/* 16px mínimo: evita el zoom automático de iPhone al tocar el campo */
.form-input {
  width: 100%;
  min-height: 46px;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 11px 14px;
  color: var(--text-primary);
  font-size: 16px;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-input:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(74, 124, 100, 0.15);
}

.form-input.invalid {
  border-color: var(--feedback-incorrect);
}

select.form-input {
  appearance: none;
  -webkit-appearance: none;
  padding-right: 30px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath d='M1 1l5 5 5-5' fill='none' stroke='%234a6356' stroke-width='2'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 11px center;
}

.setup-error {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--feedback-incorrect);
  background: var(--feedback-incorrect-bg);
  border: 1px solid #efc5c5;
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  margin-bottom: 18px;
}

.field-error {
  font-size: 0.8rem;
  color: var(--feedback-incorrect);
}

.birth-group {
  border: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 22px;
}

.birth-group legend {
  margin-bottom: 6px;
}

.birth-selects {
  display: grid;
  grid-template-columns: 0.8fr 1.4fr 1fr;
  gap: 10px;
}

.privacy-box {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  margin-bottom: 24px;
}

.privacy-title {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.privacy-text {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.checkbox-container {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  cursor: pointer;
  user-select: none;
}

.checkbox-container input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border: 2px solid var(--border-subtle);
  border-radius: 5px;
  background: var(--bg-input);
  cursor: pointer;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
}

.checkbox-container input[type="checkbox"]:checked {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
}

.checkbox-container input[type="checkbox"]:checked::after {
  content: "✓";
  color: #ffffff;
  font-size: 14px;
  font-weight: 700;
}

.checkbox-label {
  font-size: 0.9rem;
  font-weight: 500;
  line-height: 1.4;
  padding-top: 1px;
}

.btn-primary {
  width: 100%;
  min-height: 52px;
  padding: 14px 24px;
  background: var(--accent-primary);
  color: #ffffff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1.05rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: background 0.2s ease, opacity 0.2s ease;
  box-shadow: 0 4px 14px rgba(74, 124, 100, 0.25);
}

.btn-primary:active:not(:disabled) {
  background: var(--accent-primary-hover);
}

.btn-primary:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  box-shadow: none;
}

/* ========================================================
   EXPERIMENTO (limpio y neutro)
   Las 4 comparaciones siempre en una fila: posiciones 1-4 de izquierda
   a derecha, igual que en la hoja de registro.
   ======================================================== */
.experiment-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: clamp(28px, 7vh, 64px);
  width: 100%;
  max-width: 1080px;
  min-height: min(620px, calc(100dvh - 48px));
  background: #edf2ef;
  border: 4px solid transparent;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 40px 24px;
  transition: border-color 0.15s, box-shadow 0.15s, background-color 0.15s;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}

.experiment-container.feedback-correct {
  border-color: var(--feedback-correct);
  background-color: var(--feedback-correct-bg);
  box-shadow: 0 0 30px var(--feedback-correct-glow);
}

.experiment-container.feedback-incorrect {
  border-color: var(--feedback-incorrect);
  background-color: var(--feedback-incorrect-bg);
  box-shadow: 0 0 30px var(--feedback-incorrect-glow);
}

/* Intervalo entre ensayos: pantalla limpia */
.experiment-container.iee-active .stimulus-box,
.experiment-container.iee-active .options-grid {
  visibility: hidden;
}

.stimulus-box {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px 40px;
  max-width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
}

.stimulus-box img {
  display: block;
  height: 95px;
  max-width: 100%;
  object-fit: contain;
  pointer-events: none;
}

.options-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  width: 100%;
  max-width: 920px;
}

.option-card {
  appearance: none;
  -webkit-appearance: none;
  font: inherit;
  color: inherit;
  background: #ffffff;
  border: 2px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 26px 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 180px;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

@media (hover: hover) {
  .option-card:hover:not(:disabled) {
    border-color: var(--accent-primary);
    box-shadow: 0 8px 20px rgba(74, 124, 100, 0.16);
  }
}

.option-card:active:not(:disabled) {
  border-color: var(--accent-primary);
}

.option-card:disabled {
  cursor: default;
}

.option-card img {
  display: block;
  height: 110px;
  max-width: 100%;
  object-fit: contain;
  pointer-events: none;
}

/* ========================================================
   PANTALLA FINAL (participante)
   ======================================================== */
.results-card {
  max-width: 520px;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.results-title {
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 22px;
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  width: 100%;
  margin-bottom: 22px;
}

.stat-card {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px 12px;
}

.stat-label {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 6px;
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.sync-status {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  line-height: 1.4;
  text-align: left;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface-elevated);
  color: var(--text-secondary);
}

.status-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: currentColor;
  flex-shrink: 0;
}

.sync-status.sending .status-dot,
.sync-status.retrying .status-dot {
  animation: blink 1s ease-in-out infinite;
}

.sync-status.retrying {
  color: #9a6b12;
  background: #fdf7e8;
  border-color: #f0dfb4;
}

.sync-status.saved {
  color: var(--feedback-correct);
  background: var(--feedback-correct-bg);
  border-color: #bfe3cf;
}

.sync-status.error {
  color: var(--feedback-incorrect);
  background: var(--feedback-incorrect-bg);
  border-color: #efc5c5;
}

/* Explicación final y solución */
.debrief {
  width: 100%;
  text-align: left;
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
}

.debrief-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.debrief-subtitle {
  font-size: 1rem;
  font-weight: 700;
  margin: 22px 0 10px;
}

.debrief-text {
  font-size: 0.93rem;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 10px;
}

.debrief-text strong {
  color: var(--text-primary);
}

.debrief-warning {
  margin-top: 16px;
  font-size: 0.85rem;
  line-height: 1.5;
  color: #9a6b12;
  background: #fdf7e8;
  border: 1px solid #f0dfb4;
  border-radius: var(--radius-sm);
  padding: 10px 14px;
}

.solution-head,
.solution-row {
  display: grid;
  grid-template-columns: 1fr 28px 1fr;
  align-items: center;
  gap: 8px;
}

.solution-head {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 6px;
}

.solution-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.solution-row {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px;
}

.solution-figure {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  min-width: 0;
}

.solution-figure img {
  height: 54px;
  max-width: 100%;
  object-fit: contain;
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  padding: 6px 8px;
}

.solution-figure figcaption {
  font-size: 0.78rem;
  color: var(--text-secondary);
  text-align: center;
  line-height: 1.3;
}

.solution-arrow {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent-primary);
  text-align: center;
}

@keyframes blink {
  50% { opacity: 0.25; }
}

/* ========================================================
   MÓVIL
   ======================================================== */
@media (max-width: 640px) {
  .main-content {
    padding-top: 16px;
    padding-bottom: max(16px, env(safe-area-inset-bottom));
    align-items: flex-start;
  }

  .glass-card {
    padding: 22px 18px;
  }

  .instruction-lead {
    font-size: 1rem;
    padding: 16px 16px;
    margin-bottom: 20px;
  }

  .form-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .birth-selects {
    gap: 8px;
  }

  /* Experimento a pantalla casi completa */
  .main-content:has(#screen-experiment:not([hidden])) {
    padding: 8px;
    align-items: stretch;
  }

  .experiment-container {
    min-height: calc(100dvh - 16px);
    padding: 24px 10px;
    border-radius: var(--radius-md);
  }

  .stimulus-box {
    padding: 16px 22px;
  }

  .stimulus-box img {
    height: 80px;
  }

  .options-grid {
    gap: 8px;
  }

  .option-card {
    min-height: 120px;
    padding: 16px 4px;
    border-radius: 10px;
  }

  .option-card img {
    height: 64px;
  }

  .results-title {
    font-size: 1.25rem;
  }
}