/* ============================================================
   Quon — Obsidian Gold Edition
   Visual sibling of xiu.kr. Gold accent (#d4a016) + teal (#2dd4a8),
   Space Grotesk display + Outfit body + Fira Code mono, layered grid + glow.
   Class vocabulary kept stable for script.js DOM hooks.
   ============================================================ */

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

:root {
  /* ── base surfaces ── */
  --bg:               #07070b;
  --bg-deep:          #030305;
  --bg-surface:       #0e0e15;
  --bg-card:          #13131d;
  --bg-card-hover:    #1a1a28;
  --surface:          #0e0e15;          /* legacy alias */
  --surface-dim:      #0a0a12;
  --surface-raised:   #13131d;
  --surface-hover:    #1a1a28;

  /* ── accents (xiu.kr gold) ── */
  --accent:           #d4a016;
  --accent-bright:    #e8b227;
  --accent-dim:       #b8891a;
  --accent-glow:      rgba(212, 160, 22, 0.15);
  --accent-glow-strong: rgba(212, 160, 22, 0.30);
  --accent-ghost:     rgba(212, 160, 22, 0.06);

  --teal:             #2dd4a8;
  --teal-dim:         rgba(45, 212, 168, 0.12);
  --secondary:        #2dd4a8;
  --secondary-glow:   rgba(45, 212, 168, 0.22);

  /* ── text ── */
  --text:             #e4e4ec;
  --text-strong:      #f5f5fa;
  --text-secondary:   #8a8aa6;
  --text-muted:       #6e6e88;
  --text-dim:         #4a4a5e;

  /* ── lines ── */
  --border:           #1e1e30;
  --border-strong:    #2a2a44;
  --border-hover:     #2a2a44;

  /* ── status ── */
  --danger:           #ef5a6b;
  --danger-glow:      rgba(239, 90, 107, 0.18);

  /* ── geometry ── */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-pill: 100px;

  /* ── shadows ── */
  --shadow-xs: 0 1px 0 rgba(255, 255, 255, 0.03) inset, 0 1px 2px rgba(0, 0, 0, 0.35);
  --shadow-sm: 0 1px 0 rgba(255, 255, 255, 0.04) inset, 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 1px 0 rgba(255, 255, 255, 0.05) inset, 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 1px 0 rgba(255, 255, 255, 0.06) inset, 0 20px 60px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 24px var(--accent-glow-strong), 0 0 48px var(--accent-glow);

  /* ── type stacks ── */
  --font-display: "Space Grotesk", "Pretendard Variable", Pretendard, "Apple SD Gothic Neo", sans-serif;
  --font-body:    "Outfit", "Pretendard Variable", Pretendard, "Apple SD Gothic Neo", -apple-system, sans-serif;
  --font-mono:    "Fira Code", "Pretendard Variable", "SFMono-Regular", "JetBrains Mono", monospace;

  /* ── motion ── */
  --ease-out:    cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
}

html, body {
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  font-feature-settings: "ss01", "cv11";
  line-height: 1.6;
  letter-spacing: -0.005em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  position: relative;
}

::selection {
  background: var(--accent);
  color: var(--bg);
}

/* ============================================================
   Skip link
   ============================================================ */
.skip-link {
  position: absolute;
  top: -40px;
  left: 1rem;
  z-index: 1000;
  padding: 0.5rem 1rem;
  background: var(--accent);
  color: var(--bg);
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-decoration: none;
  transition: top 0.2s var(--ease-out);
}
.skip-link:focus { top: 1rem; }

/* ============================================================
   Grain overlay (xiu.kr signature)
   ============================================================ */
.grain::after {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.03;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='200' height='200'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0  0 0 0 0 0  0 0 0 0 0  0 0 0 0.6 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
}

/* ============================================================
   Hero background — dual radial + grid lines
   ============================================================ */
.hero-bg {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(ellipse 60% 50% at 70% 40%, rgba(212, 160, 22, 0.06), transparent 70%),
    radial-gradient(ellipse 40% 60% at 20% 80%, rgba(45, 212, 168, 0.04), transparent 60%);
}

.hero-grid-lines {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 80px 80px;
  opacity: 0.35;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 50%, black 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 50%, black 0%, transparent 70%);
}

/* legacy atmosphere wrappers — kept inert in case anything probes them */
.atmosphere, .atmosphere-grid, .atmosphere-glow, .atmosphere-noise {
  display: none !important;
}

/* ============================================================
   Site nav (fixed, blur, scroll-reactive)
   ============================================================ */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding: 1.1rem clamp(1.25rem, 4vw, 3rem);
  background: rgba(7, 7, 11, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: background 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}
.site-nav.scrolled {
  background: rgba(7, 7, 11, 0.92);
  border-bottom-color: var(--border);
}
.nav-logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
  color: var(--accent);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}
.nav-logo::before {
  content: '◇';
  font-size: 0.75em;
  color: var(--accent);
  opacity: 0.85;
}
.nav-links {
  display: flex;
  gap: 2.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  position: relative;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 0.4rem 0;
  transition: color 0.25s var(--ease-out);
}
.nav-links a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  height: 1.5px;
  width: 0;
  background: var(--accent);
  transition: width 0.3s var(--ease-out);
}
.nav-links a:where(:hover, :focus-visible) {
  color: var(--text);
}
.nav-links a:where(:hover, :focus-visible)::after {
  width: 100%;
}
.nav-end {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.language-switcher {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  padding: 0.4rem 1.1rem 0.4rem 0.8rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color 0.25s var(--ease-out), color 0.25s var(--ease-out);
  appearance: none;
  -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--text-secondary) 50%),
                    linear-gradient(135deg, var(--text-secondary) 50%, transparent 50%);
  background-position: calc(100% - 14px) 50%, calc(100% - 9px) 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  padding-right: 1.8rem;
}
.language-switcher:hover,
.language-switcher:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
  outline: none;
}
.language-switcher option {
  background: var(--bg-card);
  color: var(--text);
}
.nav-privacy {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.25s var(--ease-out);
}
.nav-privacy:where(:hover, :focus-visible) { color: var(--accent); }

/* ============================================================
   Section labels & headings
   ============================================================ */
.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.25rem;
}
.section-label::before {
  content: '';
  width: 32px;
  height: 1px;
  background: var(--accent);
  display: inline-block;
}
.section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--text-strong);
  margin-bottom: 1rem;
}

/* ============================================================
   Hero
   ============================================================ */
main {
  position: relative;
  z-index: 1;
}

.hero {
  position: relative;
  padding: clamp(7rem, 14vh, 10rem) clamp(1.25rem, 5vw, 4rem) clamp(3rem, 6vh, 4rem);
  max-width: 1400px;
  margin: 0 auto;
}
.hero-content {
  max-width: 880px;
}
.hero-headline {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.75rem, 7vw, 5.75rem);
  line-height: 1.02;
  letter-spacing: -0.035em;
  margin: 0 0 1.5rem;
  white-space: pre-line;
  background: linear-gradient(135deg, var(--text) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.hero-tagline {
  font-family: var(--font-body);
  font-size: clamp(1rem, 1.4vw, 1.2rem);
  line-height: 1.65;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 0 2.5rem;
}

.stats {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(1.5rem, 4vw, 3.5rem);
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  margin-top: 1rem;
}
.stat { display: flex; flex-direction: column; gap: 0.4rem; }
.stat-num {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  letter-spacing: -0.02em;
  color: var(--accent);
  line-height: 1;
}
.stat-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

/* ============================================================
   Workspace (2-column tool)
   ============================================================ */
.workspace {
  position: relative;
  padding: clamp(2rem, 4vh, 3rem) clamp(1.25rem, 5vw, 4rem) clamp(4rem, 8vh, 6rem);
  max-width: 1400px;
  margin: 0 auto;
}
.workspace-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
  align-items: start;
}
.workspace-control {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.workspace-preview {
  position: sticky;
  top: 6rem;
}

/* ── tab bar (filter-pill row) ── */
.tab-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding: 1rem;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-card-hover), var(--bg-card));
}
.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 44px;
  padding: 0.6rem 1.1rem;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
}
.tab-btn svg { width: 14px; height: 14px; }
.tab-btn:where(:hover, :focus-visible) {
  border-color: var(--accent-dim);
  color: var(--accent);
}
.tab-btn.active {
  background: var(--accent-glow);
  border-color: var(--accent);
  color: var(--accent);
}

.tab-panels {
  padding: clamp(1.25rem, 3vw, 2rem);
}
.tab-panel { display: none; }
.tab-panel.active { display: block; animation: fadeIn 0.35s var(--ease-out); }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.panel-section + .panel-section {
  margin-top: 2rem;
}
.panel-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
  color: var(--text-strong);
  margin: 0 0 1rem;
}
.panel-title-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}
.panel-title-row .panel-title { margin: 0; }

/* ── type selector (chunky cards · Variant B cards × xiu.kr gold) ── */
.type-selector {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
}
@media (max-width: 720px) {
  .type-selector { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0.6rem; }
}
@media (max-width: 380px) {
  .type-selector { grid-template-columns: 1fr; }
}

.type-btn {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto;
  grid-template-areas:
    "num    icon"
    "name   icon"
    "desc   desc";
  gap: 0.15rem 0.75rem;
  min-height: 44px;
  padding: 0.95rem 1.05rem 0.9rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text);
  text-align: left;
  cursor: pointer;
  transition:
    transform 0.25s var(--ease-out),
    border-color 0.25s var(--ease-out),
    background 0.25s var(--ease-out),
    box-shadow 0.25s var(--ease-out);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.03) inset,
    2px 3px 0 rgba(0, 0, 0, 0.35);
}

/* per-card tints cycle gold → teal → muted so the grid reads as a deck */
.type-btn:nth-child(1) {
  background:
    linear-gradient(155deg, rgba(212, 160, 22, 0.10), transparent 65%),
    var(--bg-card);
}
.type-btn:nth-child(3) {
  background:
    linear-gradient(155deg, rgba(45, 212, 168, 0.10), transparent 65%),
    var(--bg-card);
}
.type-btn:nth-child(5) {
  background:
    linear-gradient(155deg, rgba(45, 212, 168, 0.06), transparent 60%),
    var(--bg-card);
}
.type-btn:nth-child(6) {
  background:
    linear-gradient(155deg, rgba(212, 160, 22, 0.07), transparent 60%),
    var(--bg-card);
}

.type-btn-num {
  grid-area: num;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.22em;
  color: var(--text-muted);
  text-transform: uppercase;
}
.type-btn-icon {
  grid-area: icon;
  align-self: start;
  justify-self: end;
  font-size: 1.35rem;
  line-height: 1;
  filter: saturate(0.95);
  transition: transform 0.3s var(--ease-out);
}
.type-btn-name {
  grid-area: name;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.015em;
  color: var(--text-strong);
  line-height: 1.15;
  margin-top: 0.3rem;
}
.type-btn-desc {
  grid-area: desc;
  font-family: var(--font-body);
  font-size: 0.74rem;
  line-height: 1.35;
  color: var(--text-secondary);
  margin-top: 0.3rem;
}

.type-btn:where(:hover, :focus-visible) {
  border-color: var(--accent-dim);
  transform: translate(-1px, -2px);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.05) inset,
    3px 5px 0 rgba(0, 0, 0, 0.45),
    0 0 0 1px var(--accent-glow-strong);
}
.type-btn:where(:hover, :focus-visible) .type-btn-icon {
  transform: translateY(-1px) rotate(-2deg);
}

.type-btn.active {
  background:
    linear-gradient(155deg, var(--accent-glow-strong), transparent 70%),
    var(--bg-card);
  border-color: var(--accent);
  box-shadow:
    0 1px 0 rgba(255, 255, 255, 0.06) inset,
    3px 5px 0 rgba(0, 0, 0, 0.5),
    0 0 0 1px var(--accent);
}
.type-btn.active .type-btn-num { color: var(--accent-bright); }
.type-btn.active .type-btn-name { color: var(--text-strong); }

@media (prefers-reduced-motion: reduce) {
  .type-btn,
  .type-btn-icon { transition: none; }
  .type-btn:where(:hover, :focus-visible) { transform: none; }
  .type-btn:where(:hover, :focus-visible) .type-btn-icon { transform: none; }
}

/* ============================================================
   Forms / inputs
   ============================================================ */
.form-container { display: none; }
.form-container.active { display: block; animation: fadeIn 0.3s var(--ease-out); }

.form-section-title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin: 1.25rem 0 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px dashed var(--border);
}
.form-section-title:first-child { margin-top: 0; }

.form-group { margin-bottom: 1rem; }
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.85rem;
}
.form-row .form-group { margin-bottom: 1rem; }

.form-group label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}
.form-group .required { color: var(--accent); margin-left: 0.25rem; }
.form-group .optional {
  color: var(--text-muted);
  font-size: 0.85em;
  letter-spacing: 0.05em;
  text-transform: none;
  margin-left: 0.35rem;
}
.form-group small {
  display: block;
  margin-top: 0.4rem;
  color: var(--text-muted);
  font-size: 0.78rem;
  line-height: 1.5;
}

.input-field {
  width: 100%;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.75rem 0.95rem;
  color: var(--text);
  font-family: var(--font-body);
  /* 16px minimum prevents iOS Safari focus auto-zoom. */
  font-size: 1rem;
  line-height: 1.5;
  transition: border-color 0.2s var(--ease-out), box-shadow 0.2s var(--ease-out), background 0.2s var(--ease-out);
}
.input-field::placeholder { color: var(--text-muted); }
.input-field:hover { border-color: var(--border-strong); }
.input-field:focus,
.input-field:focus-visible {
  outline: none;
  border-color: var(--accent);
  background: var(--bg-card);
  box-shadow: 0 0 0 3px var(--accent-glow);
}
.input-field.is-invalid {
  border-color: var(--danger);
  box-shadow: 0 0 0 3px var(--danger-glow);
}
textarea.input-field { resize: vertical; min-height: 96px; font-family: var(--font-body); }
select.input-field {
  appearance: none;
  -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--text-secondary) 50%),
                    linear-gradient(135deg, var(--text-secondary) 50%, transparent 50%);
  background-position: calc(100% - 18px) 50%, calc(100% - 13px) 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  padding-right: 2.4rem;
}
select.input-field option { background: var(--bg-card); color: var(--text); }

.input-sm {
  padding: 0.55rem 0.75rem;
  /* 16px minimum prevents iOS Safari focus auto-zoom. */
  font-size: 1rem;
}
.select-sm {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  padding: 0.5rem 2rem 0.5rem 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  appearance: none;
  -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--text-secondary) 50%),
                    linear-gradient(135deg, var(--text-secondary) 50%, transparent 50%);
  background-position: calc(100% - 14px) 50%, calc(100% - 9px) 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  cursor: pointer;
  transition: border-color 0.2s var(--ease-out);
}
.select-sm:hover, .select-sm:focus-visible { border-color: var(--accent); outline: none; }
.select-sm option { background: var(--bg-card); color: var(--text); }

.checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 44px;
  padding: 0.25rem 0;
  font-family: var(--font-body);
  font-size: 0.9rem;
  color: var(--text);
  cursor: pointer;
  text-transform: none;
  letter-spacing: 0;
}
.checkbox-label input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  background: var(--bg-surface);
  cursor: pointer;
  position: relative;
  transition: all 0.2s var(--ease-out);
}
.checkbox-label input[type="checkbox"]:checked {
  background: var(--accent);
  border-color: var(--accent);
}
.checkbox-label input[type="checkbox"]:checked::after {
  content: '';
  position: absolute;
  inset: 4px;
  background: var(--bg);
  clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0, 43% 62%);
}

.color-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}
.color-input {
  width: 100%;
  height: 48px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-surface);
  cursor: pointer;
  padding: 4px;
  transition: border-color 0.2s var(--ease-out);
}
.color-input:where(:hover, :focus-visible) { border-color: var(--accent); }
.color-input::-webkit-color-swatch-wrapper { padding: 0; }
.color-input::-webkit-color-swatch { border: none; border-radius: 6px; }

.field-error {
  display: block;
  margin-top: 0.4rem;
  color: var(--danger);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.04em;
}

/* advanced details */
.advanced-details {
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.9rem;
  margin-bottom: 1rem;
}
.advanced-details summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-secondary);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.advanced-details summary::before {
  content: '+';
  color: var(--accent);
  font-weight: 700;
  transition: transform 0.2s var(--ease-out);
}
.advanced-details[open] summary::before {
  content: '−';
}
.advanced-details summary::-webkit-details-marker { display: none; }
.advanced-details-body { padding-top: 0.85rem; }

/* design groups */
.design-group {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1rem 1.15rem;
  margin-bottom: 0.85rem;
  background: var(--bg-surface);
  transition: border-color 0.2s var(--ease-out);
}
.design-group:where(:hover, :focus-within) { border-color: var(--border-strong); }
.design-group > summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text);
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.design-group > summary::after {
  content: '+';
  color: var(--accent);
  font-weight: 700;
  font-size: 1.1rem;
  transition: transform 0.2s var(--ease-out);
}
.design-group[open] > summary::after { content: '−'; }
.design-group > summary::-webkit-details-marker { display: none; }
.design-group-body {
  padding-top: 1rem;
  margin-top: 0.85rem;
  border-top: 1px dashed var(--border);
}

/* ============================================================
   Buttons
   ============================================================ */
.btn-generate {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  margin-top: 1.25rem;
  padding: 1rem 2rem;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
}
.btn-generate:where(:hover, :focus-visible) {
  background: var(--accent-bright);
  box-shadow: 0 0 30px var(--accent-glow-strong);
  transform: translateY(-1px);
}
.btn-generate:active { transform: translateY(0); }
.btn-generate.is-loading { opacity: 0.7; cursor: progress; }

.form-hint {
  margin-top: 0.75rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}

.btn-sm {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  border-radius: var(--radius-pill);
  padding: 0.4rem 0.95rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.2s var(--ease-out);
}
.btn-sm:where(:hover, :focus-visible) {
  border-color: var(--accent);
  color: var(--accent);
}
.btn-sm--danger { color: var(--danger); border-color: rgba(239, 90, 107, 0.3); }
.btn-sm--danger:where(:hover, :focus-visible) { border-color: var(--danger); color: var(--danger); }

.btn-export {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.85rem 1.5rem;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
}
.btn-export:where(:hover, :focus-visible):not(:disabled) {
  background: var(--accent-bright);
  box-shadow: 0 0 24px var(--accent-glow-strong);
}
.btn-export:disabled {
  background: var(--bg-card-hover);
  color: var(--text-muted);
  cursor: not-allowed;
}
.btn-export--outline {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}
.btn-export--outline:where(:hover, :focus-visible):not(:disabled) {
  background: var(--accent-glow);
  color: var(--accent);
}
.btn-export--outline:disabled {
  border-color: var(--border);
  color: var(--text-muted);
  background: transparent;
}
.export-actions {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.btn-icon {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 50%;
  color: var(--text-secondary);
  font-size: 1rem;
  cursor: pointer;
  transition: all 0.2s var(--ease-out);
}
.btn-icon:where(:hover, :focus-visible) {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-glow);
}

/* ============================================================
   Highlight cards (presets, history, pins)
   ============================================================ */
.preset-btn,
.custom-preset-btn,
.pin-slot,
.history-list li:not(.history-empty) {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  width: 100%;
  text-align: left;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.85rem 1rem;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
}
.preset-btn:where(:hover, :focus-visible),
.custom-preset-btn:where(:hover, :focus-visible),
.pin-slot:where(:hover, :focus-visible),
.history-list li:not(.history-empty):where(:hover, :focus-visible) {
  border-color: var(--accent-dim);
  background: var(--bg-card-hover);
  transform: translateX(4px);
}
.preset-btn.is-active {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent-glow);
}

.pin-slot {
  align-items: flex-start;
  min-height: 64px;
}
.pin-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}
.pin-empty {
  font-family: var(--font-body);
  font-size: 0.85rem;
  color: var(--text-muted);
  font-style: italic;
}
.pin-content {
  font-size: 0.9rem;
  color: var(--text);
}

.history-pins {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin: 1rem 0;
}
.history-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 1rem 0 0.5rem;
}
.history-toolbar .input-sm { flex: 1 1 140px; min-width: 0; }
.history-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.history-empty {
  background: transparent !important;
  border: 1px dashed var(--border) !important;
  color: var(--text-muted) !important;
  text-align: center;
  font-style: italic;
  padding: 1.5rem !important;
  cursor: default !important;
}
.history-empty:hover { transform: none !important; border-color: var(--border) !important; }
.history-hint {
  color: var(--text-secondary);
  font-size: 0.85rem;
  margin-bottom: 0.25rem;
}

/* ============================================================
   Preview (hero portrait analogue)
   ============================================================ */
.preview-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: clamp(1.5rem, 3vw, 2.25rem);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
}
.preview-stage {
  position: relative;
  width: 100%;
  aspect-ratio: 1 / 1;
  max-width: 360px;
  display: grid;
  place-items: center;
  isolation: isolate;
}
.preview-stage.is-empty .preview-canvas-shell {
  background: transparent;
  border: 1px dashed var(--border-strong);
}

.hero-image-glow {
  position: absolute;
  inset: -10%;
  border-radius: 50%;
  background: radial-gradient(circle at center,
    var(--accent-glow-strong) 0%,
    var(--accent-glow) 35%,
    transparent 70%);
  filter: blur(20px);
  z-index: -1;
  animation: pulseGlow 4s var(--ease-in-out) infinite;
  pointer-events: none;
}

@keyframes pulseGlow {
  0%, 100% { opacity: 0.6; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.05); }
}

.hero-orbit {
  position: absolute;
  inset: -8%;
  border: 1px dashed rgba(212, 160, 22, 0.4);
  border-radius: 50%;
  animation: orbit 20s linear infinite;
  pointer-events: none;
  z-index: 0;
}
.hero-orbit-dot {
  position: absolute;
  top: -3px;
  left: 50%;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 12px var(--accent), 0 0 24px var(--accent-glow);
  transform: translateX(-50%);
}
@keyframes orbit {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.preview-canvas-shell {
  position: relative;
  z-index: 1;
  background: #ffffff;
  border-radius: var(--radius-md);
  padding: 1rem;
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
  transition: transform 0.25s var(--ease-out);
  overflow: hidden;
}
#qr-code-container {
  display: grid;
  place-items: center;
  width: 100%;
  height: 100%;
}
#qr-code-container canvas,
#qr-code-container svg {
  max-width: 100%;
  height: auto;
  display: block;
}

.preview-status {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
  text-align: center;
  min-height: 1.2em;
}

.preview-zoom-controls {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
}
.preview-zoom-controls span {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  min-width: 3.5em;
  text-align: center;
}

/* ============================================================
   FAQ
   ============================================================ */
.faq {
  position: relative;
  padding: clamp(3rem, 6vh, 5rem) clamp(1.25rem, 5vw, 4rem) clamp(4rem, 8vh, 6rem);
  max-width: 1100px;
  margin: 0 auto;
  border-top: 1px solid var(--border);
}
.faq-list {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.faq-list details {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.4rem;
  transition: border-color 0.25s var(--ease-out);
}
.faq-list details:where(:hover, :focus-within) { border-color: var(--accent-dim); }
.faq-list details[open] { border-color: var(--accent); }
.faq-list summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--text-strong);
  letter-spacing: -0.01em;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: '+';
  color: var(--accent);
  font-size: 1.4rem;
  font-weight: 700;
  transition: transform 0.25s var(--ease-out);
  flex-shrink: 0;
}
.faq-list details[open] summary::after { transform: rotate(45deg); }
.faq-list .faq-answer {
  margin-top: 0.85rem;
  padding-top: 0.85rem;
  border-top: 1px dashed var(--border);
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ============================================================
   Tags
   ============================================================ */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.65rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
}
.tag.featured {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 0 12px var(--accent-glow);
}
.tag.teal {
  border-color: var(--teal);
  color: var(--teal);
  background: var(--teal-dim);
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  position: relative;
  padding: 2.5rem clamp(1.25rem, 5vw, 4rem);
  border-top: 1px solid var(--border);
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  color: var(--text-secondary);
}
.footer-brand {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text);
}
.footer-links {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}
.footer-links a {
  color: var(--text-secondary);
  text-decoration: none;
  margin: 0 0.35rem;
  transition: color 0.2s var(--ease-out);
}
.footer-links a:where(:hover, :focus-visible) { color: var(--accent); }

/* ============================================================
   Bottom ad banner
   ============================================================ */
.ad-banner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1rem clamp(1.25rem, 5vw, 4rem);
  text-align: center;
}

/* ============================================================
   Reveal-on-scroll
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s var(--ease-out), transform 0.8s var(--ease-out);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

/* ============================================================
   Notifications
   ============================================================ */
.notification {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 200;
  background: var(--bg-card);
  border: 1px solid var(--accent);
  border-radius: var(--radius-md);
  padding: 0.85rem 1.25rem;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.05em;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5), 0 0 24px var(--accent-glow);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.3s var(--ease-out), transform 0.3s var(--ease-out);
}
.notification.show { opacity: 1; transform: translateY(0); }

/* ============================================================
   Scrollbar
   ============================================================ */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover { background: var(--accent-dim); }
* { scrollbar-width: thin; scrollbar-color: var(--border-strong) var(--bg); }

/* ============================================================
   Legacy hidden helpers
   ============================================================ */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============================================================
   Dynamic viewport height (dvh) override.
   Keeps `vh` rules above as the fallback for older browsers
   (Safari < 15.4), while modern engines use `dvh` to avoid
   reflow when the iOS Safari address bar hides/shows.
   ============================================================ */
@supports (height: 100dvh) {
  html, body { min-height: 100dvh; }
  .hero {
    padding: clamp(7rem, 14dvh, 10rem) clamp(1.25rem, 5vw, 4rem) clamp(3rem, 6dvh, 4rem);
  }
  .workspace {
    padding: clamp(2rem, 4dvh, 3rem) clamp(1.25rem, 5vw, 4rem) clamp(4rem, 8dvh, 6rem);
  }
  .faq {
    padding: clamp(3rem, 6dvh, 5rem) clamp(1.25rem, 5vw, 4rem) clamp(4rem, 8dvh, 6rem);
  }
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 1000px) {
  .workspace-grid {
    grid-template-columns: 1fr;
  }
  .workspace-preview {
    position: static;
    order: -1;
  }
  .nav-links { display: none; }
}

@media (max-width: 720px) {
  .site-nav {
    padding: 0.85rem 1.25rem;
  }
  .nav-end { gap: 0.6rem; }
  .nav-privacy { display: none; }
  .hero {
    padding-top: 6rem;
  }
  .hero-headline {
    font-size: clamp(2.5rem, 12vw, 3.75rem);
  }
  .stats { gap: 1.5rem; padding-top: 1.5rem; }
  .stat-num { font-size: 1.4rem; }
  .form-row { grid-template-columns: 1fr; }
  .color-row { grid-template-columns: 1fr; }
  .history-pins { grid-template-columns: 1fr; }
  .ad-banner { padding: 0.5rem 1rem; }
}

/* ============================================================
   prefers-reduced-motion
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .hero-image-glow,
  .hero-orbit { animation: none !important; }
  .reveal { opacity: 1 !important; transform: none !important; }
}