/* === CSS Variables (swap these for re-skinning) === */
:root {
  --color-bg: #FDFBF7;
  --color-surface: #FFFFFF;
  --color-text: #1A1A1A;
  --color-text-secondary: #6B7280;
  --color-primary: #6B4FBB;
  --color-primary-light: #EDE9F6;
  --color-border: #E5E7EB;
  --color-error: #DC2626;
  --font-body: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Noto Serif SC', serif;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 2px 8px rgba(0,0,0,0.06);
  --max-width: 420px;
  --transition: all 0.3s ease;
}

/* === Reset === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
}

/* === Layout === */
.app {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px 20px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.page {
  display: none;
  flex: 1;
  flex-direction: column;
}

.page.active {
  display: flex;
}

/* === Page: Unlock === */
.unlock-page {
  justify-content: center;
  align-items: center;
  text-align: center;
  gap: 32px;
}

.unlock-icon {
  font-size: 48px;
  width: 88px;
  height: 88px;
  background: var(--color-primary-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.unlock-title {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 600;
  color: var(--color-text);
}

.unlock-form {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.input-field {
  width: 100%;
  padding: 14px 16px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 16px;
  font-family: var(--font-body);
  text-align: center;
  letter-spacing: 2px;
  background: var(--color-surface);
  transition: var(--transition);
  color: var(--color-text);
}

.input-field:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(107, 79, 187, 0.1);
}

.input-field::placeholder {
  color: var(--color-text-secondary);
  letter-spacing: 0;
}

.btn {
  width: 100%;
  padding: 14px 24px;
  border: none;
  border-radius: var(--radius);
  font-size: 16px;
  font-family: var(--font-body);
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

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

.btn-primary:active {
  transform: scale(0.98);
  opacity: 0.9;
}

.error-msg {
  color: var(--color-error);
  font-size: 14px;
  min-height: 20px;
}

/* === Page: Start === */
.start-page {
  justify-content: center;
  align-items: center;
  text-align: center;
  gap: 24px;
}

.start-title {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 700;
  line-height: 1.4;
}

.start-subtitle {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  max-width: 320px;
}

.start-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--color-text-secondary);
  background: var(--color-primary-light);
  padding: 6px 14px;
  border-radius: 20px;
}

.start-btn {
  margin-top: 16px;
}

/* === Page: Quiz === */
.quiz-page {
  gap: 24px;
}

.quiz-header {
  display: flex;
  align-items: center;
  gap: 12px;
}

.quiz-back {
  width: 36px;
  height: 36px;
  border: none;
  background: var(--color-surface);
  border-radius: 50%;
  font-size: 18px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  flex-shrink: 0;
  color: var(--color-text);
}

.quiz-back:active { transform: scale(0.95); }
.quiz-back:disabled { opacity: 0.3; pointer-events: none; }

.quiz-progress-wrap {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.quiz-counter {
  font-size: 13px;
  color: var(--color-text-secondary);
  text-align: right;
}

.quiz-progress {
  height: 6px;
  background: var(--color-border);
  border-radius: 3px;
  overflow: hidden;
}

.quiz-progress-bar {
  height: 100%;
  background: var(--color-primary);
  border-radius: 3px;
  transition: width 0.3s ease;
}

.quiz-question {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.5;
  text-align: center;
  padding: 8px 0;
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.quiz-option {
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  padding: 16px 18px;
  font-size: 15px;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
  line-height: 1.5;
  color: var(--color-text);
}

.quiz-option:active {
  transform: scale(0.98);
  border-color: var(--color-primary);
  background: var(--color-primary-light);
}

/* === Page: Result === */
.result-page {
  gap: 24px;
  align-items: center;
}

.result-card {
  width: 100%;
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  color: #fff;
  position: relative;
  overflow: hidden;
}

.result-label {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.3;
}

.result-short {
  font-size: 15px;
  opacity: 0.9;
  line-height: 1.6;
}

.result-detail {
  width: 100%;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow);
}

.result-detail-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-bottom: 12px;
}

.result-full-text {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.8;
  white-space: pre-line;
}

.result-actions {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.btn-save {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.result-brand {
  font-size: 12px;
  color: var(--color-text-secondary);
  text-align: center;
  padding-top: 8px;
}

/* === Share Image Container (hidden, for html2canvas) === */
.share-image-container {
  position: absolute;
  left: -9999px;
  top: 0;
  width: 375px;
}

/* === Error Page === */
.error-page {
  justify-content: center;
  align-items: center;
  text-align: center;
  gap: 16px;
}

.error-icon { font-size: 48px; }

.error-title {
  font-size: 18px;
  font-weight: 600;
}

.error-text {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* === Loading === */
.loading {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 200px;
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* === Image Preview Overlay === */
.image-preview-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.image-preview-hint {
  color: rgba(255, 255, 255, 0.8);
  font-size: 14px;
  margin-bottom: 16px;
}

.image-preview-img {
  max-width: 100%;
  max-height: 70vh;
  border-radius: 12px;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
  -webkit-touch-callout: default;
}

.image-preview-close {
  position: absolute;
  top: env(safe-area-inset-top, 16px);
  right: 16px;
  margin-top: 16px;
  width: 36px;
  height: 36px;
  border: none;
  background: rgba(255, 255, 255, 0.2);
  color: #fff;
  font-size: 18px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}