/* Walkthrough section — interactive video + chapter list */
.walkthrough {
  padding: 88px 56px; border-bottom: 1px solid #2a2722;
  background: var(--charcoal);
}
.walkthrough .wt-head {
  display: flex; justify-content: space-between; align-items: flex-end;
  margin-bottom: 40px; flex-wrap: wrap; gap: 20px;
}
.walkthrough .wt-head h2 {
  font-family: 'Archivo Black'; font-size: clamp(36px, 4.4vw, 64px);
  margin: 0; letter-spacing: -0.02em; line-height: 0.95;
}
.walkthrough .wt-head h2 .alt { color: var(--yellow); }
.walkthrough .wt-head .lead {
  max-width: 380px; color: #b5b0a2; font-size: 15px; line-height: 1.5; margin: 0;
}
.walkthrough .wt-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 24px;
  align-items: start;
}
.vplayer {
  position: relative; aspect-ratio: 16/10;
  background: var(--black); border: 1px solid #2a2722;
  overflow: hidden; display: flex; flex-direction: column;
  width: 100%; min-width: 0;
}
.vplayer .vstage {
  flex: 1; position: relative; overflow: hidden;
  background:
    radial-gradient(circle at 50% 40%, rgba(232,214,14,0.06), transparent 60%),
    var(--black);
}
.vplayer .vstage::before {
  content: ""; position: absolute; inset: 0;
  background-image:
    repeating-linear-gradient( 0deg, transparent 0 22px, rgba(232,214,14,0.06) 22px 23px),
    repeating-linear-gradient(90deg, transparent 0 22px, rgba(232,214,14,0.06) 22px 23px);
  mask-image: radial-gradient(circle at 50% 50%, black 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(circle at 50% 50%, black 30%, transparent 75%);
}
.vplayer .vlabel-tl, .vplayer .vlabel-tr {
  position: absolute; top: 14px; font-family: 'Space Mono', monospace;
  font-size: 11px; letter-spacing: 0.12em; text-transform: uppercase; z-index: 4;
}
.vplayer .vlabel-tl { left: 70px; color: var(--yellow);}
.vplayer .vlabel-tr {
  right: 56px; top: 18px; color: var(--pink); display: inline-flex; align-items: center; gap: 6px;
}
.vplayer .vlabel-tr::before {
  content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--pink);
  animation: blink 1.4s ease-in-out infinite;
}
@keyframes blink { 50% { opacity: 0.25; } }

.vmute {
  position: absolute; top: 12px; right: 12px; z-index: 6;
  width: 34px; height: 34px; border-radius: 50%;
  background: rgba(0,0,0,0.55); border: 1px solid #2a2722;
  color: var(--white); cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  transition: all .15s; backdrop-filter: blur(6px);
}
.vmute:hover { background: var(--yellow); color: var(--black); border-color: var(--yellow);}
.vmute.muted { background: var(--pink); color: var(--black); border-color: var(--pink);}

.vside-wrap {
  position: sticky; top: 76px;
  align-self: start;
  display: block;
}
@media (max-width: 1024px) {
  .vside-wrap { position: relative; top: auto; }
}
/* Floating panic stop/play button (top-left corner of video) */
.vpanic {
  position: absolute; top: 12px; left: 12px; z-index: 6;
  display: inline-flex; align-items: center; gap: 8px;
  height: 34px; padding: 0 14px 0 6px;
  background: rgba(0,0,0,0.55); border: 1px solid #2a2722;
  border-radius: 999px;
  color: var(--white); cursor: pointer;
  transition: all .15s; backdrop-filter: blur(6px);
  font-family: 'Space Mono', monospace; font-size: 11px; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
}
.vpanic:hover { background: var(--pink); color: var(--black); border-color: var(--pink);}
.vpanic.paused:hover { background: var(--yellow); color: var(--black); border-color: var(--yellow);}
.vpanic .vpanic-dot {
  width: 22px; height: 22px; border-radius: 50%;
  background: currentColor; color: var(--black);
  display: inline-flex; align-items: center; justify-content: center;
}
.vpanic .vpanic-hint {
  opacity: 0.6; font-size: 9px; letter-spacing: 0.14em; margin-left: 4px;
}

/* sequencer scene */
.vscene {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 18px; padding: 24px;
}
.vscene .step-grid {
  display: grid; grid-template-columns: repeat(16, 1fr); gap: 6px;
  width: min(90%, 640px); position: relative;
}
.vscene .step {
  aspect-ratio: 1; border-radius: 2px;
  background: #14110c; border: 1px solid #2a2722;
  transition: all .35s cubic-bezier(.7,0,.2,1);
  position: relative;
}
.vscene .step.lit { background: var(--yellow); border-color: var(--yellow); box-shadow: 0 0 12px rgba(232,214,14,0.5); }
.vscene .step.lit.pink { background: var(--pink); border-color: var(--pink); box-shadow: 0 0 12px rgba(212,168,174,0.5); }
.vscene .step.lit.white { background: var(--white); border-color: var(--white); box-shadow: 0 0 12px rgba(244,241,232,0.5); }
.vscene .step.head { outline: 2px solid var(--white); outline-offset: 2px; }
.vscene .cluster-overlay {
  position: absolute; top: -6px; bottom: -6px;
  border: 1.5px dashed; border-radius: 6px;
  transition: all .45s cubic-bezier(.7,0,.2,1);
  pointer-events: none; opacity: 0;
}
.vscene .cluster-overlay.show { opacity: 1;}
.vscene .cluster-overlay.c1 { border-color: var(--yellow);}
.vscene .cluster-overlay.c2 { border-color: var(--pink);}
.vscene .cluster-overlay.c3 { border-color: var(--white);}
.vscene .scene-callout {
  font-family: 'Space Mono', monospace; font-size: 13px; letter-spacing: 0.06em;
  color: var(--yellow); text-transform: uppercase;
  text-shadow: 0 0 12px rgba(232,214,14,0.5);
  text-align: center; transition: opacity .25s;
}
.vscene .mod-badges { display: flex; gap: 8px; flex-wrap: wrap; justify-content: center; }
.vscene .mod-badge {
  font-family: 'Space Mono', monospace; font-size: 10px; font-weight: 700;
  letter-spacing: 0.1em; text-transform: uppercase;
  padding: 5px 10px; border-radius: 999px;
  background: rgba(232,214,14,0.12); color: var(--yellow);
  border: 1px solid rgba(232,214,14,0.4);
  animation: modPulse 1.6s ease-in-out infinite;
}
.vscene .mod-badge.pink { background: rgba(212,168,174,0.12); color: var(--pink); border-color: rgba(212,168,174,0.4);}
@keyframes modPulse { 0%, 100% { transform: translateY(0);} 50% { transform: translateY(-3px);} }

/* control bar */
.vcontrols {
  background: linear-gradient(180deg, transparent, rgba(0,0,0,0.9));
  padding: 28px 22px 18px; z-index: 5; position: relative;
}
.vscrubber {
  position: relative; height: 6px; background: #2a2722;
  border-radius: 3px; cursor: pointer; margin-bottom: 14px;
}
.vscrubber .vfill {
  position: absolute; left: 0; top: 0; bottom: 0;
  background: var(--yellow); border-radius: 3px; transition: width .12s linear;
}
.vscrubber .vhandle {
  position: absolute; top: 50%; width: 16px; height: 16px;
  border-radius: 50%; background: var(--white); border: 2px solid var(--yellow);
  transform: translate(-50%, -50%); transition: left .12s linear;
  box-shadow: 0 0 10px rgba(232,214,14,0.5);
}
.vscrubber .vtick {
  position: absolute; top: -6px; bottom: -6px; width: 2px;
  background: #4a463d; transform: translateX(-50%); pointer-events: none;
}
.vscrubber .vtick.active { background: var(--pink); }
.vrow { display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.vrow .vleft { display: flex; align-items: center; gap: 14px; }
.vplay {
  width: 44px; height: 44px; border-radius: 50%; border: none;
  background: var(--yellow); color: var(--black);
  display: inline-flex; align-items: center; justify-content: center;
  cursor: pointer; transition: transform .15s;
}
.vplay:hover { transform: scale(1.06); background: var(--white);}
.vtime { font-family: 'Space Mono', monospace; font-size: 12px; color: #d7d3c5; letter-spacing: 0.06em;}
.vtime b { color: var(--yellow); font-weight: 700; }
.vrate {
  font-family: 'Space Mono', monospace; font-size: 11px; color: #807a6c;
  letter-spacing: 0.12em; text-transform: uppercase;
  padding: 6px 10px; border: 1px solid #2a2722; border-radius: 999px;
  cursor: pointer; background: transparent; transition: all .15s;
}
.vrate:hover, .vrate.on { color: var(--yellow); border-color: var(--yellow);}

/* chapter list */
.wt-chapters {
  display: flex; flex-direction: column; gap: 1px;
  background: #2a2722; border: 1px solid #2a2722;
}
.wt-chapter {
  background: var(--black); padding: 22px 24px; cursor: pointer;
  transition: all .2s ease;
  border-left: 3px solid transparent;
  display: grid; grid-template-columns: 1fr 32px; gap: 18px;
  align-items: baseline;
}
.wt-chapter:hover { background: #15130f;}
.wt-chapter.active { background: #15130f; border-left-color: var(--yellow); }
.wt-chapter .cmeta {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: 'Space Mono', monospace; font-size: 12px;
  color: #807a6c; letter-spacing: 0.12em; margin-bottom: 6px;
  text-transform: uppercase;
}
.wt-chapter .cmeta .ctime { color: #c9c5b8; font-weight: 700; letter-spacing: 0.08em;}
.wt-chapter.active .cmeta .ctime { color: var(--yellow);}
.wt-chapter .cmeta .csep { color: #4a463d; }
.wt-chapter .cnum {
  font-family: 'Space Mono', monospace; font-size: 11px; color: #807a6c;
  text-align: right; padding-top: 4px;
}
.wt-chapter .ctitle {
  font-family: 'Archivo Black'; font-size: 24px; margin: 0;
  letter-spacing: -0.01em; line-height: 1.1;
  transition: color .2s;
}
.wt-chapter.active .ctitle { color: var(--yellow);}
.wt-chapter .cbody {
  margin: 0; font-size: 14px; line-height: 1.5;
  color: #c9c5b8; text-wrap: pretty;
  max-height: 0; opacity: 0; overflow: hidden;
  transition: max-height .4s cubic-bezier(.7,0,.2,1), opacity .25s ease, margin .4s ease;
}
.wt-chapter.active .cbody {
  max-height: 240px; opacity: 1; margin-top: 10px;
}
.wt-chapter .ctags {
  display: flex; gap: 6px; flex-wrap: wrap;
  max-height: 0; overflow: hidden;
  transition: max-height .4s cubic-bezier(.7,0,.2,1), margin .4s ease;
}
.wt-chapter.active .ctags { max-height: 50px; margin-top: 14px; }
.wt-chapter .ctag {
  font-family: 'Space Mono', monospace; font-size: 10px; font-weight: 700;
  letter-spacing: 0.08em; text-transform: uppercase;
  padding: 4px 8px; border-radius: 2px;
  background: rgba(232,214,14,0.18); color: var(--yellow);
}
.wt-chapter .ctag.pink { background: rgba(212,168,174,0.18); color: var(--pink);}

@media (max-width: 1024px) { .walkthrough .wt-grid { grid-template-columns: 1fr; } }
@media (max-width: 900px) { .walkthrough { padding: 56px 24px;} }