/* Paleta y escala visual coherente para un formulario auditivo largo. */
:root {
  --bg: #f8f7f2;
  --bg-gradient: radial-gradient(circle at 10% 10%, #fffde8 0%, #f8f7f2 38%, #f2f5ff 100%);
  --ink: #172033;
  --ink-soft: #4a556f;
  --panel: #ffffff;
  --panel-border: #d9deea;
  --accent: #3d6cff;
  --accent-soft: #e7edff;
  --ok: #147a36;
  --error: #c62828;
  font-family: "Avenir Next", "Inter", "Segoe UI", Arial, sans-serif;
}

[data-theme="dark"] {
  --bg: #0d1117;
  --bg-gradient: radial-gradient(circle at 10% 10%, #111827 0%, #0d1117 48%, #090c10 100%);
  --ink: #d9e1ee;
  --ink-soft: #9aa6bf;
  --panel: #131a24;
  --panel-border: #263244;
  --accent: #5f8cff;
  --accent-soft: #1a2538;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 2.2rem 1rem 3.25rem;
  color: var(--ink);
  background: var(--bg);
  background-image: var(--bg-gradient);
}

.container {
  width: min(980px, 100%);
  margin: 0 auto;
}

.header {
  padding: 1.2rem 1.4rem;
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  background: linear-gradient(140deg, #ffffff 0%, #f8f9ff 100%);
  box-shadow: 0 6px 18px rgba(21, 31, 56, 0.08);
}

[data-theme="dark"] .header {
  background: linear-gradient(140deg, #121926 0%, #1a2331 100%);
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.45);
}

.eyebrow {
  margin: 0;
  font-size: 0.79rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
}

.header--compact {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.header--compact .eyebrow {
  margin: 0;
}

.header--compact .theme-toggle {
  margin-top: 0;
  flex-shrink: 0;
}

.header h1 {
  margin: 0.35rem 0 0.35rem;
  font-size: clamp(1.45rem, 3vw, 2rem);
}

.muted {
  margin: 0;
  color: var(--ink-soft);
  line-height: 1.5;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  padding: 1.15rem 1.25rem;
  margin-top: 1rem;
}

.theme-toggle {
  margin-top: 0.95rem;
  width: auto;
  min-width: 140px;
  padding: 0.45rem 0.8rem;
  font-size: 0.9rem;
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
  box-shadow: none;
}

.theme-toggle:hover {
  background: var(--accent-soft);
  transform: none;
  box-shadow: none;
}

#trial-list .trial-card {
  margin-top: 0;
}

.step-lead {
  margin: 0;
  color: var(--ink-soft);
  line-height: 1.58;
}

.step-instructions {
  margin: 0.3rem 0 0.45rem 1.15rem;
  padding: 0;
}

.step-instructions li {
  margin: 0.58rem 0;
  line-height: 1.58;
  color: var(--ink-soft);
}

.welcome-card {
  background: linear-gradient(160deg, #f7faff 0%, #eef3ff 100%);
}

[data-theme="dark"] .welcome-card {
  background: linear-gradient(160deg, #152236 0%, #121c2d 100%);
}

.thank-you-card {
  text-align: center;
  padding: 1.6rem 1.25rem;
  background: linear-gradient(160deg, #f2fff6 0%, #eef8ff 100%);
}

[data-theme="dark"] .thank-you-card {
  background: linear-gradient(160deg, #132819 0%, #121f2d 100%);
}

.thank-you-card h3 {
  font-size: clamp(1.35rem, 3vw, 1.75rem);
}

.participant-code-wrap {
  margin-top: 1.35rem;
  padding: 1.1rem 1rem;
  border: 1px dashed var(--panel-border);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.55);
}

[data-theme="dark"] .participant-code-wrap {
  background: rgba(0, 0, 0, 0.2);
}

.participant-code-label {
  margin: 0 0 0.45rem;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--ink-soft);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.participant-code {
  margin: 0;
  font-size: clamp(1.65rem, 5vw, 2.2rem);
  font-weight: 800;
  letter-spacing: 0.12em;
  color: var(--accent);
  font-family: "SF Mono", "Menlo", "Consolas", monospace;
}

.participant-code-hint {
  margin: 0.75rem 0 0;
  font-size: 0.92rem;
  line-height: 1.5;
  color: var(--ink-soft);
}

.section-title {
  margin: 0.35rem 0 0.85rem;
  font-size: 1.05rem;
}

.progress-wrap {
  margin-bottom: 0.9rem;
}

.progress-bar {
  width: 100%;
  height: 12px;
  border-radius: 999px;
  background: #e5eaf5;
  overflow: hidden;
}

.progress-fill {
  width: 0%;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, #7a9dff 0%, #3d6cff 100%);
  transition: width 220ms ease;
}

.progress-text {
  margin: 0.45rem 0 0;
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 0.92rem;
}

.stepper {
  display: grid;
  gap: 0.7rem;
  margin-top: 1rem;
  margin-bottom: 0.85rem;
}

.stepper-nav-group {
  display: flex;
  gap: 0.6rem;
}

.stepper-track {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 0.45rem;
  flex-wrap: wrap;
}

.stepper-nav {
  width: auto;
  min-width: 100px;
  margin: 0;
  padding: 0.5rem 0.8rem;
  background: #e9eeff;
  color: #1f3b86;
  border: 1px solid #bfd0ff;
  box-shadow: none;
}

.stepper-nav:hover {
  background: #dce6ff;
  transform: none;
  box-shadow: none;
}

.stepper-nav:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.stepper-nav--submit {
  background: linear-gradient(135deg, #2f9e4f 0%, #1f7a3a 100%);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 8px 16px rgba(31, 122, 58, 0.25);
}

.stepper-nav--submit:hover:not(:disabled) {
  background: linear-gradient(135deg, #35b059 0%, #248a42 100%);
  transform: translateY(-1px);
  box-shadow: 0 10px 18px rgba(31, 122, 58, 0.32);
}

[data-theme="dark"] .stepper-nav--submit {
  background: linear-gradient(135deg, #3cb868 0%, #2a8f4c 100%);
  color: #fff;
}

.step-bullet {
  width: 34px;
  height: 34px;
  margin: 0;
  border-radius: 999px;
  border: 1px solid #cfd8eb;
  background: #eef2f8;
  color: #7a88a8;
  font-weight: 700;
  box-shadow: none;
  padding: 0;
  opacity: 0.55;
  transition: opacity 160ms ease, background-color 160ms ease, color 160ms ease;
}

.step-bullet.is-disabled,
.step-bullet:disabled {
  cursor: not-allowed;
  filter: grayscale(0.3);
}

.step-bullet.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  opacity: 1;
}

[data-theme="dark"] .progress-bar {
  background: #222d3f;
}

[data-theme="dark"] .stepper-nav {
  background: #1c283a;
  border-color: #3a4d70;
  color: #dce6ff;
}

[data-theme="dark"] .stepper-nav:hover {
  background: #24344e;
}

[data-theme="dark"] .step-bullet {
  background: #1a2231;
  border-color: #3b4b68;
  color: #7788a8;
  opacity: 0.5;
}

[data-theme="dark"] .step-bullet.active {
  opacity: 1;
  color: #ffffff;
}

.participant-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0.9rem;
  margin-bottom: 1rem;
}

.participant-field {
  min-width: 0;
}

label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

input,
select,
textarea,
button {
  width: 100%;
  font: inherit;
  padding: 0.6rem 0.7rem;
  border: 1px solid #b5bfd4;
  border-radius: 10px;
  background: var(--panel);
  color: var(--ink);
}

select option {
  color: var(--ink);
  background: var(--panel);
}

input:focus,
select:focus,
textarea:focus {
  outline: 2px solid #bdd0ff;
  border-color: var(--accent);
}

.trial-card {
  border: 1px solid #dde2ef;
  border-radius: 14px;
  padding: 0.9rem;
  margin-top: 0.9rem;
  background: #fcfcff;
}

[data-theme="dark"] .trial-card {
  background: #111925;
  border-color: #2a384d;
}

.trial-card h3 {
  margin: 0 0 0.65rem;
}

.intro-card {
  background: linear-gradient(160deg, #f7faff 0%, #eef3ff 100%);
}

[data-theme="dark"] .intro-card {
  background: linear-gradient(160deg, #152236 0%, #121c2d 100%);
}

.intro-list {
  margin: 0.5rem 0 0.9rem 1rem;
  padding: 0;
}

.intro-list li {
  margin: 0.35rem 0;
}

.intro-check {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  margin-top: 0.5rem;
}

.intro-check input[type="checkbox"] {
  margin-top: 0.15rem;
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
}

.audio-row {
  display: block;
  width: 100%;
  margin-top: 0.4rem;
  margin-bottom: 0.45rem;
}

.audio-player {
  margin-bottom: 0.6rem;
}

.audio-play-btn {
  width: 100%;
  margin: 0;
  padding: 0.95rem 0.95rem;
  font-size: 1rem;
  border-radius: 12px;
  background: linear-gradient(135deg, #4a73ff 0%, #315af2 100%);
  color: #fff;
}

.audio-player--compact {
  margin-bottom: 0;
  margin-left: auto;
}

.audio-play-btn--compact {
  width: 48px;
  min-width: 48px;
  height: 48px;
  padding: 0;
  border-radius: 10px;
  font-size: 1.15rem;
  line-height: 1;
}

.audio-row {
  display: none;
}

.reference-known-group {
  margin: 0.25rem 0 0.85rem;
}

.reference-known-label {
  margin: 0 0 0.45rem;
  font-weight: 600;
}

.reference-known-options {
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.reference-known-option {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  border: 1px solid #ccd6ec;
  border-radius: 10px;
  padding: 0.42rem 0.55rem;
  cursor: pointer;
  background: #fff;
}

.reference-known-radio {
  appearance: none;
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  margin: 0;
  border: 2px solid #8ea2d3;
  border-radius: 6px;
  background: #fff;
  position: relative;
}

.reference-known-radio:checked {
  background: var(--accent);
  border-color: var(--accent);
}

.reference-known-radio:checked::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 1px;
  width: 7px;
  height: 12px;
  border: solid #fff;
  border-width: 0 3px 3px 0;
  transform: rotate(45deg);
}

[data-theme="dark"] .reference-known-option {
  background: #172234;
  border-color: #3e5276;
}

[data-theme="dark"] .reference-known-radio {
  background: #172234;
  border-color: #5874a8;
}

.candidate-option {
  border: 1px solid #d5ddee;
  border-radius: 12px;
  padding: 0.65rem;
  margin-bottom: 0.6rem;
  background: #fff;
}

.candidate-option:has(input:checked) {
  border-color: var(--accent);
  background: var(--accent-soft);
}

[data-theme="dark"] .candidate-option {
  background: #131d2b;
  border-color: #33445f;
}

.candidate-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.45rem;
}

.candidate-controls {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.candidate-radio {
  appearance: none;
  -webkit-appearance: none;
  width: 28px;
  height: 28px;
  margin: 0;
  border: 2px solid #8ea2d3;
  border-radius: 7px;
  background: #fff;
  cursor: pointer;
  position: relative;
  flex: 0 0 auto;
}

.candidate-radio:checked {
  background: var(--accent);
  border-color: var(--accent);
}

.candidate-radio:checked::after {
  content: "";
  position: absolute;
  left: 7px;
  top: 2px;
  width: 8px;
  height: 14px;
  border: solid #fff;
  border-width: 0 3px 3px 0;
  transform: rotate(45deg);
}

.candidate-label {
  margin: 0;
  font-weight: 700;
  flex: 1;
}

.candidate-header label {
  margin: 0;
  font-weight: 700;
}

[data-theme="dark"] .candidate-radio {
  background: #172234;
  border-color: #5874a8;
}

.form-footer {
  margin-top: 1.2rem;
  border-top: 1px solid #e4e8f2;
  padding-top: 1rem;
}

.is-hidden {
  display: none;
}

button {
  margin-top: 0.8rem;
  border: none;
  background: linear-gradient(135deg, #4a73ff 0%, #315af2 100%);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 8px 16px rgba(50, 84, 225, 0.22);
}

button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 18px rgba(50, 84, 225, 0.28);
}

.status {
  margin-top: 0.9rem;
  font-weight: 700;
}

.status.success {
  color: var(--ok);
}

.status.error {
  color: var(--error);
}

@media (max-width: 640px) {
  .stepper-nav-group .stepper-nav {
    flex: 1;
  }

  .audio-play-btn {
    padding: 1.05rem 1rem;
    font-size: 1.07rem;
  }
}