:root {
  --color-bg: #f5f6f8;
  --color-surface: #ffffff;
  --color-text: #1a1d21;
  --color-text-muted: #5b6270;
  --color-border: #d8dce2;
  --color-primary: #1f6f4a;
  --color-primary-dark: #17563a;
  --color-primary-text: #ffffff;
  --color-error: #b3261e;
  --color-error-bg: #fbeceb;
  --color-success-bg: #e9f6ee;
  --color-danger: #c0392b;
  --radius: 10px;
  --tap-min: 48px;
  --max-width: 560px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.45;
  -webkit-text-size-adjust: 100%;
}

button, select, input {
  font-family: inherit;
  font-size: inherit;
}

.app {
  max-width: var(--max-width);
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--color-bg);
}

/* ---- top bar ---- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--color-bg);
  padding: 10px 16px 8px;
  border-bottom: 1px solid var(--color-border);
}

.lang-toggle {
  display: flex;
  gap: 6px;
}

.lang-btn {
  flex: 1;
  min-height: 40px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  border-radius: 8px;
  padding: 6px 4px;
  font-size: 13px;
  cursor: pointer;
}

.lang-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-text);
  font-weight: 600;
}

.progress-wrap {
  margin-top: 10px;
}

.progress-track {
  height: 6px;
  background: var(--color-border);
  border-radius: 999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--color-primary);
  width: 0%;
  transition: width 0.2s ease;
}

.progress-label {
  margin-top: 4px;
  font-size: 12px;
  color: var(--color-text-muted);
}

/* ---- main / screens ---- */

#main {
  flex: 1;
  padding: 20px 16px 32px;
}

.screen-title {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 12px;
}

.intro-text {
  color: var(--color-text-muted);
  margin: 0 0 20px;
}

/* ---- language screen ---- */

.lang-choice-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 24px;
}

.lang-choice-btn {
  min-height: var(--tap-min);
  text-align: left;
  padding: 12px 16px;
  border: 2px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 16px;
  cursor: pointer;
}

.lang-choice-btn.active {
  border-color: var(--color-primary);
  background: var(--color-success-bg);
  font-weight: 600;
}

/* ---- buttons ---- */

.btn {
  min-height: var(--tap-min);
  border-radius: var(--radius);
  border: none;
  padding: 12px 20px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
}

.btn-block { width: 100%; }

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

.btn-primary:active { background: var(--color-primary-dark); }

.btn-primary:disabled {
  background: var(--color-border);
  color: var(--color-text-muted);
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

/* ---- questions ---- */

.question-list {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.question[data-hidden="true"] {
  display: none;
}

.question-text {
  font-size: 16px;
  font-weight: 600;
  margin: 0 0 10px;
}

.question-hint {
  font-size: 13px;
  color: var(--color-text-muted);
  margin: -6px 0 10px;
}

.options-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.option-label {
  display: flex;
  align-items: center;
  min-height: var(--tap-min);
  gap: 12px;
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  cursor: pointer;
}

.option-label:has(input:checked) {
  border-color: var(--color-primary);
  background: var(--color-success-bg);
}

/* :has() fallback for older Android WebView / Samsung Internet -- JS
   toggles this class in sync with the input's checked state. */
.option-label.selected {
  border-color: var(--color-primary);
  background: var(--color-success-bg);
}

.option-label input {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  accent-color: var(--color-primary);
}

.option-label span { flex: 1; }

.other-input {
  width: 100%;
  min-height: var(--tap-min);
  padding: 10px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
  margin-top: 8px;
}

.other-input:focus {
  outline: none;
  border-color: var(--color-primary);
}

.select-wrap select {
  width: 100%;
  min-height: var(--tap-min);
  padding: 10px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
}

.select-wrap select:disabled {
  color: var(--color-text-muted);
  background: var(--color-bg);
}

/* ---- footer nav ---- */

.nav-footer {
  position: sticky;
  bottom: 0;
  padding: 12px 16px;
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
}

.nav-hint {
  font-size: 13px;
  color: var(--color-text-muted);
  text-align: center;
  margin: 0 0 8px;
}

.nav-buttons {
  display: flex;
  gap: 10px;
}

.nav-buttons .btn-secondary { flex: 1; }
.nav-buttons .btn-primary { flex: 2; }

/* ---- result screens ---- */

.result-icon {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 16px;
}

.result-icon-success {
  background: var(--color-success-bg);
  color: var(--color-primary);
}

.result-icon-error {
  background: var(--color-error-bg);
  color: var(--color-error);
}

/* ---- validation modal ---- */

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 20px;
}

.modal {
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 20px;
  width: 100%;
  max-width: 360px;
}

.modal-title {
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 8px;
}

.modal-body {
  color: var(--color-text-muted);
  margin: 0 0 16px;
}

/* ---- invalid question highlight ---- */

.question.invalid .question-text {
  color: var(--color-error);
}

.question.invalid .option-label,
.question.invalid .select-wrap select,
.question.invalid .other-input {
  border-color: var(--color-error);
}

.question.invalid {
  background: var(--color-error-bg);
  border-radius: var(--radius);
  padding: 12px;
  margin: -12px;
  transition: background 0.2s ease;
}

.question-error {
  color: var(--color-error);
  font-size: 13px;
  margin: 8px 0 0;
}

.question-limit {
  font-size: 13px;
  color: var(--color-danger, #c0392b);
  margin: 6px 0 0;
}

[hidden] { display: none !important; }