/* ============================================================
   UX/UI upgrade layer
   Visual hierarchy, interaction states and readability only.
   ============================================================ */
:root {
  --ui-ink: #11110f;
  --ui-copy: #34342f;
  --ui-muted: #58564f;
  --ui-rule: rgba(17, 17, 17, 0.16);
  --ui-rule-strong: rgba(17, 17, 17, 0.28);
  --ui-brass: #a9874c;
  --ui-brass-soft: rgba(169, 135, 76, 0.18);
  --ui-focus: #8b6c36;
}

html {
  scroll-padding-top: 86px;
}

body {
  color: var(--ui-ink);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--ui-brass-soft);
  color: var(--ui-ink);
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 2000;
  transform: translateY(calc(-100% - 20px));
  background: var(--ui-ink);
  color: #ffffff;
  border-radius: 999px;
  padding: 10px 16px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 2100;
  width: 100%;
  height: 2px;
  pointer-events: none;
  transform-origin: left center;
  transform: scaleX(var(--scroll-progress, 0));
  background: linear-gradient(90deg, var(--ui-brass), #d3b678);
}

:focus-visible {
  outline: 2px solid var(--ui-focus);
  outline-offset: 4px;
}

.header {
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(17, 17, 17, 0.08);
}

.header.scrolled {
  background: rgba(255, 255, 255, 0.98);
  border-bottom-color: var(--ui-rule);
  box-shadow: 0 10px 28px rgba(17, 17, 17, 0.07);
}

.nav a,
.menu-panel a,
.lang-switch button {
  color: var(--ui-ink);
  font-weight: 700;
}

.nav a[aria-current="page"],
.site-footer-nav a[aria-current="page"] {
  color: var(--ui-ink);
}

.nav a[aria-current="page"]::after {
  transform: scaleX(1);
}

.nav a::after {
  height: 2px;
  background: var(--ui-brass);
  bottom: -8px;
}

.lang-switch button {
  opacity: 0.7;
}

.lang-switch button.active {
  opacity: 1;
}

.lang-switch {
  gap: 0;
}

.lang-switch button {
  min-width: 24px;
  padding-inline: 5px;
}

.lang-switch button + button {
  position: relative;
}

.lang-switch button + button::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 1px;
  height: 14px;
  background: var(--ui-rule-strong);
  transform: translateY(-50%);
}

.hamburger-toggle {
  border-color: var(--ui-rule);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 8px 22px rgba(17, 17, 17, 0.08);
}

.menu-panel {
  border-color: var(--ui-rule);
  box-shadow: 0 22px 52px rgba(17, 17, 17, 0.16);
}

h1,
h2,
h3,
h4,
.hero-sub,
.section-head p,
.model-copy h3,
.model-copy p,
.product-tagline,
.cta-inner h2,
.cta-inline p,
.product-story-title,
.about-manifesto h1,
.about-origin-col h2,
.about-founder-bio h2,
.pullquote {
  color: var(--ui-ink);
}

.hero-note,
.muted,
.material-row p,
.details-row p,
.cta-inner p,
.product-desc,
.product-trait > span,
.spec-value,
.product-story-text,
.product-story-row-copy,
.about-product-text p,
.about-manifesto-sub,
.about-origin-col p,
.about-founder-bio p,
.about-approach-body p,
.site-footer-tagline {
  color: var(--ui-copy);
  font-weight: 500;
}

.eyebrow,
.hero-label,
.product-story-eyebrow,
.product-story-row-label,
.spec-label,
.product-trait strong,
.product-split .config-group legend,
.viewer-hint,
.viewer-download-btn,
.mv-ar-btn,
.concept-eyebrow,
.concept-hero-name,
.concept-scroll-label,
.site-footer-nav-label,
.site-footer-zorotech-label,
.home-statement-label,
.concept-tag {
  color: var(--ui-muted);
  font-weight: 700;
}

.section,
.cta,
.product-story-section,
.product-split,
.concept-strip-bar,
.site-footer {
  border-color: var(--ui-rule);
}

.button,
.product-cta {
  border-color: var(--ui-ink);
  color: var(--ui-ink);
  font-weight: 700;
  box-shadow: 0 0 0 rgba(17, 17, 17, 0);
}

.button:hover,
.button:focus-visible {
  background: var(--ui-ink);
  color: #ffffff;
  box-shadow: 0 12px 28px rgba(17, 17, 17, 0.16);
}

.image-frame,
.model,
.note-box,
.contact-card,
.concept-thumb,
.gallery-item {
  border-color: var(--ui-rule);
}

.model,
.concept-thumb,
.config-card,
.button,
.footer-instagram,
.footer-linkedin {
  transition:
    transform 0.24s var(--ease),
    box-shadow 0.24s var(--ease),
    border-color 0.24s var(--ease),
    background 0.24s var(--ease),
    color 0.24s var(--ease);
}

.model:hover,
.concept-thumb:hover,
.config-option:hover .config-card {
  transform: translateY(-3px);
}

.concept-thumb:hover,
.concept-thumb.is-active {
  border-color: var(--ui-ink);
}

.concept-page .concept-entry-title,
.concept-page .concept-entry-title [data-lang] {
  color: var(--ui-ink) !important;
  opacity: 1 !important;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.concept-page .concept-entry-sub,
.concept-page .concept-entry-sub [data-lang] {
  color: var(--ui-copy) !important;
  opacity: 1 !important;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.055em;
  line-height: 1.5;
}

.concept-page .concept-title-line,
.scroll-line {
  opacity: 0.6;
}

.concept-page .concept-strip-btn,
.rot-btn {
  color: var(--ui-ink);
  border-color: var(--ui-rule-strong);
}

.concept-page .concept-modal-desc {
  color: rgba(255, 255, 255, 0.82);
  font-weight: 500;
}

.concept-page .concept-modal-close,
.concept-page .concept-modal-arrow {
  color: rgba(255, 255, 255, 0.9);
  border-color: rgba(255, 255, 255, 0.34);
}

.product-story-row:hover {
  background: rgba(169, 135, 76, 0.055);
}

.product-story-row-label {
  color: var(--ui-ink);
}

.product-split .config-swatch {
  box-shadow: 0 0 0 1px var(--ui-rule-strong);
}

.product-split .config-option input:checked + .config-card .config-swatch {
  box-shadow: 0 0 0 2px var(--bg), 0 0 0 4px var(--ui-brass);
}

input,
textarea,
select {
  color: var(--ui-ink);
  min-height: 46px;
}

input:focus,
textarea:focus,
select:focus {
  border-color: var(--ui-brass);
  box-shadow: 0 0 0 3px var(--ui-brass-soft);
}

input.is-invalid,
textarea.is-invalid,
select.is-invalid,
form.has-errors input:invalid,
form.has-errors textarea:invalid,
form.has-errors select:invalid {
  border-color: #9f3b2f;
  box-shadow: 0 0 0 3px rgba(159, 59, 47, 0.12);
}

[data-form-status].is-visible {
  display: block;
  margin-bottom: 18px;
  border-radius: 6px;
  padding: 12px 14px;
  font-size: 16px;
  line-height: 1.35;
}

[data-form-status].is-success {
  background: rgba(37, 117, 76, 0.09);
  color: #1f5f3f;
  border: 1px solid rgba(37, 117, 76, 0.24);
}

[data-form-status].is-error {
  background: rgba(159, 59, 47, 0.09);
  color: #7e2f26;
  border: 1px solid rgba(159, 59, 47, 0.24);
}

.floating-whatsapp-link {
  box-shadow: 0 12px 28px rgba(17, 17, 17, 0.22);
}

.hamburger-toggle,
.lang-switch button,
.rot-btn,
.concept-strip-btn,
.gl-close,
.gl-prev,
.gl-next,
.lightbox-close,
.footer-instagram,
.footer-linkedin {
  min-width: 44px;
  min-height: 44px;
}

.site-footer {
  color: var(--ui-copy);
}

.site-footer-nav a,
.site-footer-email {
  color: var(--ui-ink);
}

@media (max-width: 760px) {
  html {
    scroll-padding-top: 68px;
  }

  .nav a,
  .menu-panel a,
  .button,
  .eyebrow,
  .product-story-eyebrow,
  .product-story-row-label,
  .spec-label,
  .product-trait strong,
  .product-split .config-group legend {
    letter-spacing: 0.1em;
  }

  .hero-note,
  .muted,
  .product-desc,
  .product-story-text,
  .product-story-row-copy,
  .about-product-text p,
  .about-manifesto-sub,
  .about-origin-col p,
  .about-founder-bio p,
  .about-approach-body p {
    color: #30302b;
  }

  .concept-page .concept-entry-title,
  .concept-page .concept-entry-title [data-lang] {
    font-size: 15px;
    letter-spacing: 0.08em;
  }

  .concept-page .concept-entry-sub,
  .concept-page .concept-entry-sub [data-lang] {
    font-size: 14px;
    letter-spacing: 0.04em;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}