/* ==========================================================================
   OgbonMath — First-time Onboarding Tour
   --------------------------------------------------------------------------
   Welcome overlay shown once per browser (localStorage flag).
   4 slides:
     1. "Meet Ogbon" — warm introduction
     2. "Ask Ogbon anything" — points at the home Ask band
     3. "Command palette ⌘K" — teaches the keyboard shortcut
     4. "Start learning" — call-to-action with 3 paths

   Triggered by design/onboarding.js on DOMContentLoaded when
   localStorage.getItem('ogbon:onboarding-seen') is missing.
   ========================================================================== */

/* ==========================================================================
   Backdrop + container
   ==========================================================================
*/
.onb-backdrop {
  position: fixed;
  inset: 0;
  z-index: var(--z-modal);
  background: var(--backdrop);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-4);
  opacity: 0;
  animation: onb-fade-in var(--dur-slow) var(--ease-calm) forwards;
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}

.onb-backdrop.closing {
  animation: onb-fade-out var(--dur) var(--ease-calm) forwards;
}

@keyframes onb-fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes onb-fade-out {
  from { opacity: 1; }
  to { opacity: 0; }
}

/* ==========================================================================
   Panel
   ==========================================================================
*/
.onb-panel {
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  max-height: 90dvh;
  background: var(--bg2);
  border: 1px solid var(--bdr);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transform: scale(0.96) translateY(10px);
  opacity: 0;
  animation: onb-panel-in var(--dur-slow) var(--ease-calm) 120ms forwards;
  font-family: var(--font-sans);
}

.onb-backdrop.closing .onb-panel {
  animation: onb-panel-out var(--dur-fast) var(--ease-calm) forwards;
}

@keyframes onb-panel-in {
  from { transform: scale(0.96) translateY(10px); opacity: 0; }
  to { transform: scale(1) translateY(0); opacity: 1; }
}

@keyframes onb-panel-out {
  from { transform: scale(1) translateY(0); opacity: 1; }
  to { transform: scale(0.98) translateY(5px); opacity: 0; }
}

/* ==========================================================================
   Skip button (top-right — always visible)
   ==========================================================================
*/
.onb-skip {
  position: absolute;
  top: var(--sp-3);
  right: var(--sp-4);
  background: transparent !important;
  border: none !important;
  color: var(--tx3) !important;
  font-family: var(--font-sans) !important;
  font-size: var(--fs-xs) !important;
  font-weight: var(--fw-medium) !important;
  letter-spacing: var(--ls-wide) !important;
  text-transform: uppercase !important;
  padding: 6px 12px !important;
  border-radius: var(--radius-sm) !important;
  cursor: pointer;
  z-index: 2;
  transition: color var(--dur-fast) var(--ease-out), background var(--dur-fast);
}

.onb-skip:hover {
  color: var(--tx1) !important;
  background: var(--hover-bg) !important;
}

/* ==========================================================================
   Slide body — each slide is absolutely positioned + opacity-toggled
   ==========================================================================
*/
.onb-slides {
  position: relative;
  flex: 1;
  min-height: 420px;
  overflow: hidden;
}

.onb-slide {
  position: absolute;
  inset: 0;
  padding: var(--sp-10) var(--sp-8) var(--sp-6);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-4);
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: opacity var(--dur-slow) var(--ease-calm),
              transform var(--dur-slow) var(--ease-calm);
}

.onb-slide.active {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

/* ==========================================================================
   Slide visuals (illustration area)
   ==========================================================================
*/
.onb-visual {
  width: 120px;
  height: 120px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 56px;
  line-height: 1;
  color: var(--ac);
  background: var(--ac-soft);
  border: 1px solid var(--ac);
  flex-shrink: 0;
  box-shadow: 0 0 0 8px color-mix(in srgb, var(--ac) 6%, transparent);
  animation: onb-visual-pulse 2.6s var(--ease-calm) infinite;
}

@keyframes onb-visual-pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.04); }
}

@media (prefers-reduced-motion: reduce) {
  .onb-visual { animation: none; }
}

/* Keyboard mnemonic visual for slide 3 */
.onb-kbd-visual {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  font-family: var(--font-mono);
  font-size: 48px;
  font-weight: var(--fw-bold);
  color: var(--tx);
  letter-spacing: -0.02em;
}

.onb-kbd-key {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 72px;
  height: 72px;
  padding: 0 var(--sp-3);
  background: var(--bg);
  border: 1px solid var(--bdr);
  border-radius: var(--radius-lg);
  box-shadow: 0 4px 0 var(--bdr2), var(--shadow);
  font-family: var(--font-sans);
  font-size: 32px;
  font-weight: var(--fw-bold);
  color: var(--ac);
}

.onb-kbd-plus {
  color: var(--tx2);
  font-family: var(--font-sans);
  font-size: 28px;
  font-weight: var(--fw-regular);
}

/* ==========================================================================
   Slide text
   ==========================================================================
*/
.onb-eyebrow {
  font-family: var(--font-sans);
  font-size: var(--fs-xs);
  font-weight: var(--fw-semibold);
  letter-spacing: var(--ls-widest);
  text-transform: uppercase;
  color: var(--ac);
}

.onb-title {
  font-family: var(--font-display);
  font-size: var(--fs-3xl);
  font-weight: var(--fw-semibold);
  line-height: var(--lh-tight);
  letter-spacing: var(--ls-tight);
  color: var(--tx);
  text-align: center;
  margin: 0;
  max-width: 18ch;
}

.onb-body {
  font-family: var(--font-serif);
  font-size: var(--fs-md);
  line-height: var(--lh-relaxed);
  color: var(--tx1);
  text-align: center;
  max-width: 42ch;
  margin: 0;
}

/* ==========================================================================
   Final slide CTA grid (3 path options)
   ==========================================================================
*/
.onb-cta-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-2);
  width: 100%;
  max-width: 380px;
  margin-top: var(--sp-3);
}

.onb-cta-btn {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: 14px 16px !important;
  background: var(--bg) !important;
  border: 1px solid var(--bdr) !important;
  border-radius: var(--radius-md) !important;
  color: var(--tx) !important;
  font-family: var(--font-sans) !important;
  font-size: var(--fs-base) !important;
  font-weight: var(--fw-medium) !important;
  text-align: left !important;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-out),
              background var(--dur-fast) var(--ease-out),
              transform var(--dur-fast) var(--ease-out);
}

.onb-cta-btn:hover {
  border-color: var(--ac) !important;
  background: var(--ac-soft) !important;
  transform: translateX(2px);
}

.onb-cta-btn:active { transform: scale(var(--active-scale)); }

.onb-cta-btn.primary {
  background: var(--ac) !important;
  color: var(--ac-tx) !important;
  border-color: var(--ac) !important;
}

.onb-cta-btn.primary:hover {
  background: var(--ac2) !important;
  border-color: var(--ac2) !important;
  color: var(--ac-tx) !important;
}

.onb-cta-icon {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--ac-soft);
  color: var(--ac);
  font-size: 16px;
  flex-shrink: 0;
}

.onb-cta-btn.primary .onb-cta-icon {
  background: rgba(255, 255, 255, 0.15);
  color: var(--ac-tx);
}

.onb-cta-label {
  flex: 1;
}

.onb-cta-chevron {
  color: var(--tx3);
  font-size: 18px;
  flex-shrink: 0;
}

.onb-cta-btn.primary .onb-cta-chevron {
  color: var(--ac-tx);
  opacity: 0.8;
}

/* ==========================================================================
   Footer — progress dots + prev/next buttons
   ==========================================================================
*/
.onb-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  padding: var(--sp-4) var(--sp-6) var(--sp-5);
  border-top: 1px solid var(--bdr);
  background: var(--bg3);
}

.onb-dots {
  display: inline-flex;
  gap: var(--sp-2);
}

.onb-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--bdr2);
  border: none;
  padding: 0;
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease-out),
              transform var(--dur-fast) var(--ease-out);
}

.onb-dot.active {
  background: var(--ac);
  transform: scale(1.3);
}

.onb-dot:hover { background: var(--tx3); }
.onb-dot.active:hover { background: var(--ac); }

.onb-nav {
  display: inline-flex;
  gap: var(--sp-2);
}

.onb-nav-btn {
  padding: 8px 18px !important;
  background: transparent !important;
  border: 1px solid var(--bdr) !important;
  border-radius: var(--radius-md) !important;
  color: var(--tx1) !important;
  font-family: var(--font-sans) !important;
  font-size: var(--fs-sm) !important;
  font-weight: var(--fw-semibold) !important;
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out);
}

.onb-nav-btn:hover {
  background: var(--hover-bg) !important;
}

.onb-nav-btn.primary {
  background: var(--ac) !important;
  color: var(--ac-tx) !important;
  border-color: var(--ac) !important;
}

.onb-nav-btn.primary:hover {
  background: var(--ac2) !important;
  border-color: var(--ac2) !important;
  color: var(--ac-tx) !important;
}

.onb-nav-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ==========================================================================
   Mobile
   ==========================================================================
*/
@media (max-width: 560px) {
  .onb-backdrop { padding: var(--sp-2); }
  .onb-panel { border-radius: var(--radius-lg); }
  .onb-slides { min-height: 380px; }
  .onb-slide { padding: var(--sp-8) var(--sp-5) var(--sp-4); }
  .onb-visual { width: 96px; height: 96px; font-size: 44px; }
  .onb-kbd-visual { font-size: 36px; }
  .onb-kbd-key { min-width: 58px; height: 58px; font-size: 24px; }
  .onb-title { font-size: var(--fs-2xl); }
  .onb-body { font-size: var(--fs-base); max-width: 36ch; }
  .onb-skip { top: var(--sp-2); right: var(--sp-2); }
  .onb-footer {
    padding: var(--sp-3) var(--sp-4) var(--sp-4);
    flex-direction: row-reverse;
    flex-wrap: wrap-reverse;
    gap: var(--sp-2);
  }
  .onb-nav { flex: 1; justify-content: flex-end; }
  .onb-dots { flex: 0 0 auto; }
}

@media (max-height: 640px) {
  .onb-slides { min-height: 320px; }
  .onb-slide { gap: var(--sp-3); padding-top: var(--sp-6); }
  .onb-visual { width: 80px; height: 80px; font-size: 36px; }
  .onb-body { font-size: var(--fs-sm); }
}