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

:root {
  --dark:    #7D5A50;
  --mid:     #B4846C;
  --light:   #E5B299;
  --cream:   #FCDEC0;
  --white:   #FFF8F2;
  --text:    #3D2B24;
  --transition-speed: 0.6s;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--cream);
  color: var(--text);
}

/* ===== Deck viewport ===== */
#deck {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
}

/* ===== Sidebar (embedded, transparent) ===== */
#sidebar {
  position: fixed;
  top: 50%;
  left: 2.5rem;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  gap: 1.6rem;
  z-index: 200;
  transition: opacity 0.4s ease;
}

.sidebar-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.25em;
  color: var(--mid);
  opacity: 0.4;
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  cursor: pointer;
  transition: opacity 0.3s ease;
  opacity: 0.3;
}

.sidebar-item:hover {
  opacity: 0.6;
}

.sidebar-item.active {
  opacity: 1;
}

.sidebar-pip {
  width: 3px;
  height: 1.4rem;
  border-radius: 2px;
  background: var(--light);
  transition: background 0.3s, height 0.3s;
  flex-shrink: 0;
}

.sidebar-item.active .sidebar-pip {
  background: var(--dark);
  height: 1.8rem;
}

.sidebar-item-label {
  font-size: 0.8rem;
  color: var(--mid);
  letter-spacing: 0.02em;
  transition: color 0.3s;
  white-space: nowrap;
}

.sidebar-item.active .sidebar-item-label {
  color: var(--dark);
  font-weight: 600;
}

.slide {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 6rem;
  opacity: 1;
  transition:
    transform var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1),
    opacity   var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
}

#slide-incoming {
  opacity: 0;
  pointer-events: none;
}

/* ===== Transition classes ===== */
/* Outgoing positions */
.slide.exit-left   { transform: translateX(-100%); opacity: 0; }
.slide.exit-right  { transform: translateX(100%);  opacity: 0; }
.slide.exit-up     { transform: translateY(-100%); opacity: 0; }
.slide.exit-down   { transform: translateY(100%);  opacity: 0; }

/* Incoming start positions (applied instantly, then removed) */
.slide.enter-from-right { transform: translateX(100%);  opacity: 0; }
.slide.enter-from-left  { transform: translateX(-100%); opacity: 0; }
.slide.enter-from-below { transform: translateY(100%);  opacity: 0; }
.slide.enter-from-above { transform: translateY(-100%); opacity: 0; }

/* Settled */
.slide.center {
  transform: translate(0, 0);
  opacity: 1;
}

/* ===== Slide content styling ===== */
.slide h1 {
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--dark);
  text-align: center;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.slide h2 {
  font-size: 2.4rem;
  font-weight: 600;
  color: var(--dark);
  text-align: center;
  line-height: 1.3;
  margin-bottom: 0.75rem;
}

.slide h3 {
  font-size: 1.6rem;
  font-weight: 500;
  color: var(--mid);
  text-align: center;
  margin-bottom: 0.5rem;
}

.slide p {
  font-size: 1.4rem;
  color: var(--text);
  text-align: center;
  line-height: 1.6;
  max-width: 48rem;
}

.slide .subtitle {
  font-size: 1.6rem;
  color: var(--mid);
  font-style: italic;
  margin-top: 0.5rem;
}

.slide .keyword {
  font-size: 5rem;
  font-weight: 700;
  color: var(--dark);
  letter-spacing: -0.02em;
  text-align: center;
}

.slide .keyword-sub {
  font-size: 1.5rem;
  color: var(--mid);
  font-style: italic;
  margin-top: 1rem;
  text-align: center;
  max-width: 36rem;
}

.slide .section-label {
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.3em;
  color: var(--light);
  margin-bottom: 2rem;
}

.slide .accent-line {
  width: 4rem;
  height: 3px;
  background: var(--light);
  border-radius: 2px;
  margin: 1.5rem auto;
}

/* ===== Dark / Title slides (inverted) ===== */
.slide.slide-dark {
  background: var(--dark);
}

.slide.slide-dark .section-label {
  color: var(--light);
  opacity: 0.5;
}

.slide.slide-dark h1 {
  color: var(--cream);
}

.slide.slide-dark .accent-line {
  background: var(--light);
  opacity: 0.4;
}

.slide.slide-dark .toc {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 1rem;
  width: 100%;
  max-width: 32rem;
}

.slide.slide-dark .toc-item {
  display: flex;
  align-items: center;
  gap: 1.8rem;
  padding: 1.2rem 0;
  border-bottom: 1px solid rgba(229, 178, 153, 0.1);
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1),
              opacity 0.3s ease;
  opacity: 0.55;
}

.slide.slide-dark .toc-item:last-child {
  border-bottom: none;
}

.slide.slide-dark .toc-item:hover {
  opacity: 1;
  transform: translateX(8px);
}

.slide.slide-dark .toc-num {
  font-size: 0.75rem;
  font-weight: 300;
  color: var(--light);
  opacity: 0.35;
  letter-spacing: 0.1em;
  font-variant-numeric: tabular-nums;
  min-width: 1.8rem;
  flex-shrink: 0;
}

.slide.slide-dark .toc-item:hover .toc-num {
  opacity: 0.7;
}

.slide.slide-dark .toc-text {
  font-size: 1.35rem;
  font-weight: 300;
  color: var(--cream);
  letter-spacing: 0.03em;
  line-height: 1.4;
}

.slide.slide-dark .toc-hint {
  display: block;
  font-size: 0.7rem;
  color: var(--light);
  opacity: 0.35;
  letter-spacing: 0.05em;
  margin-top: 0.15rem;
}

.slide.slide-dark .subtitle {
  color: var(--light);
  opacity: 0.5;
}

/* ===== Position indicator (bottom-right) ===== */
#position {
  position: fixed;
  bottom: 1.5rem;
  right: 2rem;
  font-size: 0.75rem;
  color: var(--mid);
  opacity: 0.6;
  font-variant-numeric: tabular-nums;
  z-index: 100;
}

/* ===== Persistent timer (bottom-right, left of position) ===== */
#timer {
  position: fixed;
  bottom: 1.5rem;
  right: 5.5rem;
  font-size: 0.75rem;
  color: var(--mid);
  opacity: 0.35;
  font-variant-numeric: tabular-nums;
  z-index: 100;
  cursor: pointer;
  user-select: none;
  transition: opacity 0.2s ease;
}

#timer:hover {
  opacity: 0.7;
}