:root{
  --bg:#fafafa;
  --ink:#111;
  --panel:#fff;
  --border:#ddd;
  --addr:#d93a2f;
  --type:#7a3fd0;
  --name:#1f9d55;
  --value:#1e77ff;
  --edit-bg:#fff8d6;
  --edit-line:#b59b00;
  --type-offset:70px;
  --focus:#1e77ff;
  --done:#19a974;
}

html,body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:ui-monospace,Menlo,Consolas,monospace;
}

.wrap{
  max-width:1100px;
  margin:24px auto;
  padding:0 16px 48px;
}

code{
  color:var(--focus);
  font-weight:600;
}

h1{
  font-size:18px;
  margin:0 0 10px 0;
}

h2{
  font-size:16px;
  margin:16px 0 8px 0;
}

.intro{
  margin:18px 0;
  max-width:760px;
  line-height:1.6;
  padding:14px 16px;
  border-radius:10px;
  background:linear-gradient(135deg, rgba(30,119,255,0.08), rgba(30,119,255,0.08));
  border:1px solid rgba(30,119,255,0.18);
  box-shadow:0 6px 18px rgba(0,0,0,0.04);
  font-size:18px;
}

.panel{
  padding:12px;
  border:1px solid var(--border);
  background:var(--panel);
  border-radius:8px;
}

.muted{color:#777;font-size:12px;}
.ok{color:#0a7a0a;font-weight:600;}
.err{color:#b00020;font-weight:600;}

button{
  padding:8px 10px;
  border:1px solid #ccc;
  background:#fff;
  border-radius:8px;
  cursor:pointer;
  font:inherit;
}

button[disabled]{
  opacity:.5;
  cursor:not-allowed;
}

button:hover:not([disabled]){
  background:#f1f1f1;
}

.row{
  display:grid;
  grid-template-columns:1fr 1.3fr;
  gap:16px;
  align-items:start;
}

.controls{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
  align-items:center;
  margin-top:18px;
}

#p4-code + .controls,
#p4-stage + .controls,
#p5-code + .controls,
#p5-stage + .controls{
  margin-top:10px;
}

.hidden{display:none !important;}

.codepane{
  border:1px solid var(--border);
  background:#fff;
  border-radius:8px;
  overflow:hidden;
}

.codecol{position:relative;}

.line{
  display:flex;
  align-items:center;
  gap:8px;
  padding:8px 10px;
  min-height:32px;
  border-bottom:1px solid #f2f2f2;
}

.line .line-invalid{
  margin-left:auto;
  color:#c0392b;
  font-size:16px;
}

.line:last-child{border-bottom:none;}

.ln{
  text-align:left;
  min-width:32px;
  padding-right:8px;
  color:#999;
}

.src{white-space:pre;}
.done .src{color:var(--done);}
.code-editable{
  border:1px dashed var(--edit-line);
  padding:6px 8px;
  border-radius:10px;
  min-width:140px;
  display:inline-block;
  cursor:text;
  background:var(--edit-bg);
}
.name-list{
  position:absolute;
  left:0;
  right:var(--type-offset);
  bottom:4px;
  display:flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  flex-wrap:wrap;
}
.name-list{
  color:var(--name);
  font-weight:800;
}
.name-list .name-tag{
  border:none;
  border-radius:6px;
  padding:4px 6px;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:4px;
  background:transparent;
  white-space:nowrap;
  color:var(--name);
  min-width:0;
  position:relative;
}
.name-list .name-tag.single{
  border-color:transparent;
}
.name-list .name-tag:not(.single)::after{
  content:"|";
  color:#bbb;
  margin-left:6px;
}
.name-list .name-tag.editable{
  border:none;
  background:transparent;
  min-height:24px;
}
.name-list .name-add{
  border:1px solid #ccc;
  background:#f0f0f0;
  color:#555;
  width:24px;
  height:24px;
  border-radius:4px;
  cursor:pointer;
  font-weight:700;
  line-height:1;
  padding:0;
}
.name-list .name-del{
  border:none;
  background:transparent;
  color:#c0392b;
  font-size:13px;
  cursor:pointer;
  width:16px;
  height:16px;
  line-height:1;
  padding:0;
  position:absolute;
  top:-6px;
  right:-6px;
  outline:none;
}
.code-row{
  display:flex;
  align-items:center;
  gap:6px;
}

.state-group{
  display:grid;
  grid-template-columns:repeat(auto-fit, minmax(240px,1fr));
  gap:12px;
  margin-top:8px;
}
.state-panel{
  border:1px dashed var(--border);
  border-radius:8px;
  padding:26px 12px 12px 12px;
  background:#fcfcfc;
  position:relative;
  margin-top:18px;
}
.state-heading{
  position:absolute;
  top:-32px;
  left:12px;
  transform:none;
  padding:4px 10px;
  border-radius:8px;
  background:linear-gradient(135deg, rgba(30,119,255,0.12), rgba(30,119,255,0.12));
  border:1px solid rgba(30,119,255,0.2);
  font-size:14px;
  font-weight:700;
  color:#234;
  letter-spacing:0.2px;
  text-transform:none;
  max-width:90%;
  text-align:left;
  white-space:normal;
  overflow:visible;
  text-overflow:unset;
}
.state-group.two-col{
  grid-template-columns:repeat(2, minmax(240px,1fr));
}
.state-group .state-panel.centered{
  grid-column:1/-1;
  justify-self:center;
  min-width:240px;
}

.scroll-down-btn{
  position:fixed;
  left:50%;
  bottom:24px;
  transform:translateX(-50%);
  width:48px;
  height:48px;
  border-radius:50%;
  border:1px solid rgba(0,0,0,0.18);
  background:rgba(255,255,255,0.4);
  backdrop-filter:blur(6px);
  box-shadow:0 8px 18px rgba(0,0,0,0.14);
  cursor:pointer;
  display:flex;
  align-items:center;
  justify-content:center;
  font-size:22px;
  color:#234;
  transition:opacity 0.2s ease, transform 0.2s ease;
  z-index:50;
}
.scroll-down-btn.hidden{
  opacity:0;
  pointer-events:none;
  transform:translateY(8px);
}

.boundary{
  position:relative;
  height:0;
  background:transparent;
  grid-column:1/-1;
}
.boundary::before{
  content:"";
  position:absolute;
  left:0;
  right:0;
  top:-1px;
  height:2px;
  background:linear-gradient(90deg,transparent 0,var(--focus) 40%,var(--focus) 60%,transparent 100%);
  opacity:.9;
}

.vbox{
  position:relative;
  width:150px;
  height:200px;
  margin:8px 0;
  padding-right:var(--type-offset);
}

.vbox .cell{
  position:absolute;
  left:0;
  right:var(--type-offset);
  top:46px;
  bottom:46px;
  border:2.5px solid #000;
  border-radius:12px;
  background:transparent;
  display:flex;
  align-items:center;
  justify-content:center;
  padding:10px;
}

.vbox .value{
  color:var(--value);
  caret-color:var(--value);
  font-size:22px;
  font-weight:700;
  line-height:1.2;
  min-height:26px;
  display:inline-flex;
  align-items:center;
}

.vbox .addr{
  position:absolute;
  top:10px;
  left:0;
  right:var(--type-offset);
  text-align:center;
  color:var(--addr);
  font-size:18px;
  font-weight:800;
  line-height:1.1;
  white-space:nowrap;
}

.vbox .type{
  position:absolute;
  top:50%;
  left:calc(100% - var(--type-offset) + 6px);
  right:auto;
  transform:translateY(-50%);
  color:var(--type);
  font-size:18px;
  font-weight:800;
  line-height:1.2;
  min-height:22px;
  min-width:10px;
  display:inline-flex;
  align-items:center;
  white-space:nowrap;
  text-align:left;
  padding:0 6px;
  max-width:none;
  overflow:visible;
}

.vbox .name{
  position:absolute;
  bottom:8px;
  left:0;
  right:var(--type-offset);
  text-align:center;
  color:var(--name);
  font-size:18px;
  font-weight:800;
  line-height:1.1;
  white-space:nowrap;
}

.lbl{
  position:absolute;
  font-size:11px;
  color:#555;
  letter-spacing:0.2px;
}

.lbl-addr{top:-12px;left:0;right:var(--type-offset);text-align:center;}
.cell .lbl-value{position:absolute;top:6px;left:10px;font-size:11px;color:#555;}
.lbl-type{
  top:calc(50% - 34px);
  left:calc(100% - var(--type-offset) + 6px);
  right:auto;
  transform:translateY(-50%);
  text-align:left;
  padding-left:6px;
}
.lbl-name{bottom:-8px;left:0;right:var(--type-offset);text-align:center;}

.editable{
  background:var(--edit-bg);
  border:1px dashed var(--edit-line);
  padding:1px 10px;
  border-radius:6px;
  cursor:text;
}

.editable:focus{
  outline:none;
  background:#fff3b0;
  box-shadow:0 0 0 2px rgba(181,155,0,0.25);
}
.name-text{
  outline:none !important;
}

.placeholder.muted{
  color:#777 !important;
  font-weight:600;
}

.grid{
  display:flex;
  flex-wrap:wrap;
  gap:24px 56px;
}

.vbox .delete{
  position:absolute;
  top:-8px;
  right:-8px;
  border:1px solid #ccc;
  border-radius:12px;
  padding:2px 7px;
  cursor:pointer;
  background:#fff;
}

.vbox.is-editable{
  background:transparent;
  border:none;
  transition:border-color 0.2s ease;
}
.vbox.is-editable::before{
  content:"";
  position:absolute;
  top:-14px;
  bottom:-14px;
  left:-8px;
  right:-8px;
  border:1px dashed rgba(0,0,0,0.18);
  border-radius:14px;
  pointer-events:none;
}

nav{
  margin:16px 0;
  display:flex;
  gap:12px;
  flex-wrap:wrap;
}

nav.tabs{
  background:rgba(30,119,255,0.06);
  border:1px solid rgba(30,119,255,0.2);
  padding:8px 12px;
  border-radius:10px;
}

nav.tabs a{
  color:var(--focus);
  text-decoration:none;
  border:1px solid transparent;
  padding:4px 10px;
  border-radius:6px;
  transition:border-color 0.15s ease, color 0.15s ease;
}

nav.tabs a:hover{
  border-color:var(--focus);
}

nav.tabs a.active{
  background:#e4ecff;
  color:#4a5d9d;
  border-color:rgba(30,119,255,0.3);
  cursor:default;
}

nav.tabs a.active:hover{
  border-color:rgba(30,119,255,0.3);
}

.hint-inline{
  font-size:12px;
  color:#555;
  margin-top:6px;
  max-width:360px;
}
.hint-inline code{
  color:var(--focus);
  font-weight:600;
}

.hint-link{
  padding:8px 10px;
  border:1px solid #ccc;
  background:#fff;
  border-radius:8px;
  cursor:pointer;
  font:inherit;
}

.hint-link.hidden{
  display:none !important;
}

.pulse-success{
  animation: pulse-success 1s ease-in-out infinite;
  border-color:#ccc;
  box-shadow:0 0 0 0 rgba(25,169,116,0.16);
}

@keyframes pulse-success{
  0%{background:#fff; border-color:#ccc;}
  50%{background:#d9f5e7; box-shadow:0 0 0 10px rgba(25,169,116,0.18); border-color:rgba(25,169,116,0.85);}
  100%{background:#fff; border-color:#ccc;}
}

.status-flash{
  animation: status-flash 1s ease;
}

@keyframes status-flash{
  0%{opacity:0;}
  5%{opacity:0;}
  30%{opacity:1;}
  100%{opacity:1;}
}

@media (max-width:900px){
  .row{grid-template-columns:1fr;}
  .vbox{width:100%;}
}