/* ============================================================
   Seal Name — rice paper / ink / vermillion seal aesthetic
   ============================================================ */

:root {
  /* Surfaces — rice paper cream */
  --color-bg: #f7f3ea;
  --color-surface: #fbf8f1;
  --color-surface-offset: #eee7d7;
  --color-surface-offset-2: #e5dcc7;
  --color-border: #d9cdb0;
  --color-divider: #ddd2b8;

  /* Ink */
  --color-ink: #1a1a1a;
  --color-ink-soft: #4a453c;
  --color-ink-faint: #8c8471;

  /* Vermillion seal red */
  --color-seal: #b7301f;
  --color-seal-hover: #942516;
  --color-seal-active: #7a1e12;
  --color-seal-highlight: #f2d9d2;
  --color-seal-wash: #fbeae6;

  /* Elements accent (subtle, used sparingly for trait chips) */
  --color-gold: #a97c28;

  --radius-sm: 0.3rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.9rem;
  --radius-full: 999px;

  --font-display: 'Noto Serif TC', 'Source Serif 4', serif;
  --font-accent: 'Noto Serif TC', 'Source Serif 4', serif;
  --font-serif: 'Source Serif 4', Georgia, serif;
  --font-body: 'Work Sans', 'Segoe UI', sans-serif;

  --text-xs: clamp(0.75rem, 0.72rem + 0.15vw, 0.85rem);
  --text-sm: clamp(0.875rem, 0.83rem + 0.2vw, 0.95rem);
  --text-base: clamp(1rem, 0.96rem + 0.2vw, 1.1rem);
  --text-lg: clamp(1.15rem, 1.05rem + 0.5vw, 1.4rem);
  --text-xl: clamp(1.5rem, 1.25rem + 1.1vw, 2.1rem);
  --text-2xl: clamp(2rem, 1.4rem + 2.2vw, 3.2rem);

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  --shadow-sm: 0 1px 2px rgba(40, 30, 15, 0.08);
  --shadow-md: 0 4px 14px rgba(40, 30, 15, 0.12);
  --shadow-lg: 0 12px 32px rgba(40, 30, 15, 0.16);
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-ink);
  background-color: var(--color-bg);
  background-image:
    radial-gradient(circle at 8% 12%, rgba(183, 48, 31, 0.03), transparent 42%),
    radial-gradient(circle at 92% 85%, rgba(183, 48, 31, 0.025), transparent 40%),
    repeating-linear-gradient(0deg, rgba(140, 120, 80, 0.025) 0px, rgba(140, 120, 80, 0.025) 1px, transparent 1px, transparent 3px);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding-inline: var(--space-6);
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--color-seal);
  color: #fff;
  padding: var(--space-2) var(--space-4);
  z-index: 100;
}
.skip-link:focus {
  left: var(--space-4);
  top: var(--space-4);
}

a { color: var(--color-seal); text-decoration: none; }
a:hover { text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--color-seal);
  outline-offset: 2px;
}

h1, h2, h3 {
  font-family: var(--font-serif);
  color: var(--color-ink);
  margin: 0;
  font-weight: 700;
}

.section-title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-2);
  position: relative;
  display: inline-block;
}

.section-subtitle {
  color: var(--color-ink-soft);
  font-size: var(--text-base);
  max-width: 640px;
  margin: 0 0 var(--space-8);
}

/* Brush underline accent */
.section-title::after {
  content: "";
  display: block;
  width: 64px;
  height: 6px;
  margin-top: var(--space-2);
  background: var(--color-seal);
  border-radius: var(--radius-full);
  opacity: 0.85;
  clip-path: polygon(0% 40%, 12% 10%, 30% 55%, 48% 5%, 65% 60%, 82% 15%, 100% 45%, 100% 100%, 0% 100%);
}

/* ============ Buttons ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
  min-height: 44px;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--color-seal);
  color: #fdf6f0;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { background: var(--color-seal-hover); box-shadow: var(--shadow-md); }
.btn-primary:active { background: var(--color-seal-active); }

.btn-ghost {
  background: transparent;
  color: var(--color-ink);
  border-color: var(--color-border);
}
.btn-ghost:hover { background: var(--color-surface-offset); }

.btn-large {
  padding: var(--space-4) var(--space-10);
  font-size: var(--text-base);
}

.btn-small {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-xs);
  min-height: 36px;
}

/* ============ Header ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(247, 243, 234, 0.92);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--color-divider);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-4);
}
.brand-group {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-ink);
}
.brand:hover { text-decoration: none; }
.brand-mark { color: var(--color-seal); display: inline-flex; }
.bha-mark img { display: block; width: 30px; height: 30px; object-fit: contain; }
.brand-name {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: var(--text-lg);
  letter-spacing: 0.01em;
}
.brand-divider {
  color: var(--color-divider);
  font-weight: 300;
}
.brand-parent {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  letter-spacing: 0.01em;
  white-space: nowrap;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease, color 0.15s ease;
}
.brand-parent:hover {
  color: var(--color-seal);
  border-bottom-color: var(--color-seal);
  text-decoration: none;
}
@media (max-width: 480px) {
  .brand-divider, .brand-parent { display: none; }
}
.site-nav { display: flex; gap: var(--space-6); }
.site-nav a {
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  font-weight: 500;
}
.site-nav a:hover { color: var(--color-seal); }

/* ============ Hero ============ */
.hero {
  position: relative;
  padding-block: clamp(var(--space-16), 10vw, var(--space-24)) var(--space-16);
  overflow: hidden;
}
.hero-inner { max-width: 760px; }
.hero-eyebrow {
  color: var(--color-seal);
  font-weight: 600;
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 0 0 var(--space-3);
}
.hero-title {
  font-size: var(--text-2xl);
  line-height: 1.1;
  margin-bottom: var(--space-6);
}
.hero-lede {
  font-size: var(--text-lg);
  color: var(--color-ink-soft);
  line-height: 1.6;
  margin-bottom: var(--space-8);
  max-width: 640px;
}
.hero-lede strong { color: var(--color-ink); }
.hero-actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}
.hero-seal {
  position: absolute;
  right: 4%;
  top: 50%;
  transform: translateY(-50%) rotate(-4deg);
  font-family: var(--font-display);
  font-weight: 400;
  font-size: min(30vw, 320px);
  color: var(--color-seal);
  opacity: 0.08;
  line-height: 1;
  pointer-events: none;
  user-select: none;
}

/* ============ How it works ============ */
.how { padding-block: var(--space-16); background: var(--color-surface); border-block: 1px solid var(--color-divider); }
.how-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
  margin-top: var(--space-10);
}
.how-item--wide { grid-column: span 1; }
@media (min-width: 720px) {
  .how-item--wide { grid-row: span 1; }
}
.how-item {
  padding: var(--space-6);
  background: var(--color-bg);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
}
.how-num {
  font-family: var(--font-serif);
  color: var(--color-seal);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.05em;
}
.how-item h3 {
  font-size: var(--text-lg);
  margin: var(--space-3) 0 var(--space-2);
}
.how-item p {
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  margin: 0;
  line-height: 1.6;
}

/* ============ Form ============ */
.form-section {
  padding-block: var(--space-20);
}
.form-container { max-width: 720px; }

#name-form {
  margin-top: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}
.form-row--dates { grid-template-columns: 1fr 1.4fr 1fr; }

.field {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.field label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-ink);
}

input[type="text"], select {
  font-family: var(--font-body);
  font-size: var(--text-base);
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-ink);
  min-height: 44px;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
input[type="text"]:focus, select:focus {
  border-color: var(--color-seal);
  box-shadow: 0 0 0 3px var(--color-seal-highlight);
  outline: none;
}
input[type="text"]::placeholder { color: var(--color-ink-faint); }

.field-group {
  border: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.field-group legend {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-ink);
  padding: 0;
  margin-bottom: var(--space-1);
}
.legend-hint {
  font-weight: 400;
  color: var(--color-ink-faint);
  font-size: var(--text-xs);
}
.field-hint {
  font-size: var(--text-xs);
  color: var(--color-ink-faint);
  margin: 0;
  line-height: 1.5;
}

.radio-row { display: flex; gap: var(--space-3); flex-wrap: wrap; }
.radio-pill {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-full);
  background: var(--color-surface);
  cursor: pointer;
  font-size: var(--text-sm);
  min-height: 44px;
  transition: border-color 0.15s ease, background-color 0.15s ease;
}
.radio-pill:has(input:checked) {
  border-color: var(--color-seal);
  background: var(--color-seal-wash);
  color: var(--color-seal-active);
  font-weight: 600;
}
.radio-pill input { accent-color: var(--color-seal); width: 16px; height: 16px; }

.trait-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
}
.trait-chip {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  cursor: pointer;
  font-size: var(--text-sm);
  min-height: 44px;
  transition: border-color 0.15s ease, background-color 0.15s ease, opacity 0.15s ease;
}
.trait-chip:has(input:checked) {
  border-color: var(--color-seal);
  background: var(--color-seal-wash);
  font-weight: 600;
  color: var(--color-seal-active);
}
.trait-chip.disabled {
  opacity: 0.45;
  cursor: not-allowed;
}
.trait-chip input { accent-color: var(--color-seal); width: 16px; height: 16px; flex-shrink: 0; }

.form-submit-row { display: flex; justify-content: flex-start; }

.form-error {
  color: var(--color-seal);
  font-size: var(--text-sm);
  font-weight: 600;
  margin: 0;
}

/* ============ Results ============ */
.results-section {
  padding-block: var(--space-20);
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
}
.results-section[hidden] { display: none; }

#results-subtitle { margin-bottom: var(--space-6); }

.script-toggle {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  margin-bottom: var(--space-6);
  padding: 3px;
  background: var(--color-bg);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-full);
}
.script-toggle-btn {
  appearance: none;
  border: none;
  background: transparent;
  cursor: pointer;
  padding: var(--space-2) var(--space-4);
  min-height: 40px;
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-ink-soft);
  border-radius: var(--radius-full);
  transition: background-color 0.15s ease, color 0.15s ease;
}
.script-toggle-btn.active {
  background: var(--color-seal);
  color: var(--color-surface);
  font-weight: 600;
}
.script-toggle-btn:not(.active):hover {
  background: var(--color-seal-wash);
}

.surname-picker {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-10);
  padding: var(--space-5);
  background: var(--color-bg);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
}
.surname-picker-label {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-ink);
  margin-right: var(--space-2);
}
.surname-chip {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-full);
  background: var(--color-surface);
  cursor: pointer;
  font-size: var(--text-sm);
  min-height: 40px;
  transition: border-color 0.15s ease, background-color 0.15s ease;
}
.surname-chip .surname-char {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: var(--text-lg);
  line-height: 1;
}
.surname-chip.active {
  border-color: var(--color-seal);
  background: var(--color-seal-wash);
  color: var(--color-seal-active);
  font-weight: 600;
}

.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-6);
}

.name-card {
  background: var(--color-bg);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  opacity: 0;
  transform: translateY(10px);
  animation: card-reveal 0.5s ease forwards;
}
@keyframes card-reveal {
  to { opacity: 1; transform: translateY(0); }
}

.name-card-display {
  display: flex;
  justify-content: center;
  align-items: baseline;
  gap: var(--space-1);
  padding: var(--space-6) var(--space-2);
  background: var(--color-seal-wash);
  border: 2px solid var(--color-seal);
  border-radius: var(--radius-md);
  position: relative;
}
.name-card-display .glyph {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(2.6rem, 4vw + 1rem, 4rem);
  color: var(--color-seal-active);
  line-height: 1;
  letter-spacing: 0;
}
.name-card-display .glyph.given-char {
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: background-color 0.15s ease, transform 0.15s ease;
  padding: 0 var(--space-1);
}
.name-card-display .glyph.given-char:hover,
.name-card-display .glyph.given-char:focus-visible {
  background: rgba(183, 48, 31, 0.12);
  transform: scale(1.06);
}
.swap-hint {
  position: absolute;
  bottom: -10px;
  right: 12px;
  font-size: var(--text-xs);
  background: var(--color-seal);
  color: #fff;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-weight: 600;
}

.pinyin-row {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
  font-family: var(--font-serif);
  font-size: var(--text-base);
  color: var(--color-ink-soft);
  font-style: italic;
}

.meanings-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  font-size: var(--text-sm);
}
.meanings-list li { display: flex; gap: var(--space-2); }
.meanings-list .m-char { font-family: var(--font-display); font-weight: 400; font-size: var(--text-lg); color: var(--color-seal); min-width: 1.6em; }
.meanings-list .m-text { color: var(--color-ink-soft); }
.meanings-list .m-text strong { color: var(--color-ink); font-family: var(--font-body); }

.rationale {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  line-height: 1.6;
  border-top: 1px dashed var(--color-divider);
  padding-top: var(--space-4);
  margin: 0;
}

.card-actions {
  display: flex;
  justify-content: flex-end;
}
.btn-save-seal {
  color: var(--color-seal);
  border-color: var(--color-seal-wash);
}
.btn-save-seal:hover { background: var(--color-seal-wash); border-color: var(--color-seal); }
.btn-save-seal .icon-download { flex-shrink: 0; }

.swap-picker {
  display: none;
  flex-wrap: wrap;
  gap: var(--space-2);
  padding: var(--space-3);
  background: var(--color-surface-offset);
  border-radius: var(--radius-md);
  margin-top: calc(-1 * var(--space-2));
}
.swap-picker.open { display: flex; }
.swap-picker-option {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  cursor: pointer;
  min-height: 32px;
}
.swap-picker-option:hover { border-color: var(--color-seal); }
.swap-picker-option .opt-char { font-family: var(--font-display); font-weight: 400; font-size: var(--text-base); color: var(--color-seal); }

.results-actions {
  display: flex;
  justify-content: center;
  margin-top: var(--space-10);
}

.seal-teaser {
  margin-top: var(--space-16);
  display: flex;
  gap: var(--space-5);
  align-items: flex-start;
  padding: var(--space-6);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
}
.seal-teaser-mark {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: var(--text-2xl);
  color: var(--color-seal);
  opacity: 0.7;
  line-height: 1;
  flex-shrink: 0;
}
.seal-teaser h3 { font-size: var(--text-base); margin-bottom: var(--space-1); }
.seal-teaser p { font-size: var(--text-sm); color: var(--color-ink-soft); margin: 0; line-height: 1.6; }
.seal-teaser-cta {
  display: inline-flex;
  margin-top: var(--space-3);
}

/* ============ Footer ============ */
.site-footer {
  padding-block: var(--space-10);
  border-top: 1px solid var(--color-divider);
  background: var(--color-bg);
}
.footer-inner p {
  font-size: var(--text-xs);
  color: var(--color-ink-faint);
  max-width: 720px;
  line-height: 1.6;
  margin: 0 0 var(--space-2);
}
.footer-credit { font-style: italic; }

/* ============ Responsive ============ */
@media (max-width: 860px) {
  .how-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .form-row--dates { grid-template-columns: 1fr; }
  .trait-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-seal { display: none; }
}

@media (max-width: 520px) {
  .trait-grid { grid-template-columns: 1fr; }
  .header-inner { flex-wrap: wrap; gap: var(--space-3); }
  .site-nav { gap: var(--space-4); font-size: var(--text-xs); }
  .hero-title { font-size: clamp(1.75rem, 6vw, 2.4rem); }
}