*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{background:#0c0c10;color:#ededf5;font-family:'Inter',sans-serif;font-size:16px;line-height:1.7;overflow-x:hidden}
a{color:inherit;text-decoration:none}

:root{
  --bg:#0c0c10;--bg2:#131318;--bg3:#1a1a22;--bg4:#22222d;
  --border:rgba(255,255,255,0.07);--border2:rgba(255,255,255,0.13);
  --text:#ededf5;--text2:#9090a8;--text3:#50506a;
  --accent:#7c6ff7;--accent2:#b0aaff;--accent-bg:rgba(124,111,247,0.12);
  --green:#22c98a;--green-bg:rgba(34,201,138,0.10);
  --amber:#f5a623;--amber-bg:rgba(245,166,35,0.10);
  --red:#f05454;--red-bg:rgba(240,84,84,0.10);
  --teal:#38d9c0;--teal-bg:rgba(56,217,192,0.10);
  --r:10px;--r-lg:16px;
  --mono:'JetBrains Mono',monospace;--sans:'Inter',sans-serif;
}

/* NAV */
.site-header{position:sticky;top:0;z-index:100;background:rgba(12,12,16,0.9);backdrop-filter:blur(14px);border-bottom:0.5px solid var(--border)}
.nav-inner{max-width:1100px;margin:0 auto;padding:0 1.5rem;height:56px;display:flex;align-items:center;justify-content:space-between;gap:12px}
.logo{font-family:var(--mono);font-size:15px;font-weight:500;white-space:nowrap}
.logo-bracket{color:var(--text3)}.logo-accent{color:var(--accent2)}
.nav-links{display:flex;gap:1.5rem}
.nav-link{font-size:13px;color:var(--text2);transition:color .15s;white-space:nowrap}
.nav-link:hover,.nav-link.active{color:var(--text)}

/* BUTTONS */
.btn-primary{display:inline-flex;align-items:center;gap:6px;padding:10px 22px;background:var(--accent);color:#fff;border-radius:var(--r);font-size:14px;font-weight:500;border:none;cursor:pointer;transition:opacity .15s;min-height:44px}
.btn-primary:hover{opacity:.85}
.btn-secondary{display:inline-flex;align-items:center;gap:6px;padding:10px 22px;background:transparent;color:var(--text);border-radius:var(--r);font-size:14px;font-weight:500;border:0.5px solid var(--border2);cursor:pointer;transition:background .15s;min-height:44px}
.btn-secondary:hover{background:var(--bg3)}

/* HERO */
.hero{max-width:1100px;margin:0 auto;padding:4rem 1.5rem 3rem}
.hero-eyebrow{font-size:11px;font-family:var(--mono);color:var(--accent);letter-spacing:.1em;text-transform:uppercase;margin-bottom:1.25rem}
.hero-title{font-size:clamp(2rem,5vw,3.5rem);font-weight:600;line-height:1.1;letter-spacing:-.03em;margin-bottom:1.25rem}
.hero-accent{color:var(--accent2)}
.hero-sub{font-size:17px;color:var(--text2);max-width:520px;line-height:1.65;margin-bottom:2rem}
.hero-cta{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:2.5rem}
.hero-code{max-width:620px}
.code-window{background:var(--bg2);border:0.5px solid var(--border2);border-radius:var(--r-lg);overflow:hidden}
.code-toolbar{display:flex;align-items:center;gap:6px;padding:10px 14px;border-bottom:0.5px solid var(--border);background:var(--bg3)}
.dot-red{background:#ff5f57;width:10px;height:10px;border-radius:50%}
.dot-amber{background:#febc2e;width:10px;height:10px;border-radius:50%}
.dot-green{background:#28c840;width:10px;height:10px;border-radius:50%}
.code-filename{font-family:var(--mono);font-size:12px;color:var(--text3);margin-left:4px}
.code-body{font-family:var(--mono);font-size:13px;line-height:1.75;padding:1.25rem 1.5rem;overflow-x:auto;color:var(--text);white-space:pre;-webkit-overflow-scrolling:touch}
.c-comment{color:var(--text3)}.c-kw{color:var(--accent2)}.c-method{color:var(--teal)}.c-str{color:var(--amber)}.c-num{color:var(--green)}

/* SCENARIOS */
.scenarios-section,.methods-preview{max-width:1100px;margin:0 auto;padding:3rem 1.5rem;border-top:0.5px solid var(--border)}
.section-label{font-size:11px;font-family:var(--mono);color:var(--accent);letter-spacing:.1em;text-transform:uppercase;margin-bottom:.75rem}
.section-title{font-size:clamp(1.4rem,3vw,2rem);font-weight:600;letter-spacing:-.02em;margin-bottom:1.75rem}
.scenario-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:12px}
.scenario-card{background:var(--bg2);border:0.5px solid var(--border);border-radius:var(--r-lg);padding:1.25rem;transition:border-color .2s,transform .2s,background .2s;display:block}
.scenario-card:hover{border-color:var(--accent);background:var(--bg3);transform:translateY(-2px)}
.sc-icon{font-size:1.75rem;margin-bottom:.75rem;line-height:1}
.sc-name{font-size:15px;font-weight:500;margin-bottom:4px}
.sc-desc{font-size:12px;color:var(--text2);margin-bottom:.75rem}
.sc-methods{display:flex;flex-wrap:wrap;gap:4px}
.sc-methods code{font-family:var(--mono);font-size:11px;background:var(--accent-bg);color:var(--accent2);padding:2px 7px;border-radius:5px}
.method-tag-grid{display:flex;flex-direction:column;gap:1.25rem}
.tag-group{display:flex;align-items:flex-start;gap:1rem;flex-wrap:wrap}
.tag-group-label{font-size:12px;font-family:var(--mono);padding:3px 10px;border-radius:5px;white-space:nowrap;min-width:110px;text-align:center}
.tag-group-label.mutates{background:var(--red-bg);color:var(--red)}
.tag-group-label.copy{background:var(--green-bg);color:var(--teal)}
.tag-group-label.iter{background:var(--accent-bg);color:var(--accent2)}
.tag-group-label.search{background:var(--amber-bg);color:var(--amber)}
.tag-group-label.other{background:var(--bg3);color:var(--text2)}
.tag-list{display:flex;flex-wrap:wrap;gap:6px}
.mtag{font-family:var(--mono);font-size:12px;padding:3px 9px;border-radius:5px}
.mtag.mutates{background:var(--red-bg);color:var(--red);border:0.5px solid rgba(240,84,84,.2)}
.mtag.copy{background:var(--green-bg);color:var(--teal);border:0.5px solid rgba(56,217,192,.2)}
.mtag.iter{background:var(--accent-bg);color:var(--accent2);border:0.5px solid rgba(124,111,247,.25)}
.mtag.search{background:var(--amber-bg);color:var(--amber);border:0.5px solid rgba(245,166,35,.2)}
.mtag.other{background:var(--bg3);color:var(--text2);border:0.5px solid var(--border2)}

/* FOOTER */
.site-footer{border-top:0.5px solid var(--border);margin-top:4rem}
.footer-inner{max-width:1100px;margin:0 auto;padding:1.5rem;display:flex;align-items:center;gap:1.5rem;flex-wrap:wrap}
.footer-note{font-size:13px;color:var(--text3)}
.footer-link{font-size:13px;color:var(--text2)}
.footer-link:hover{color:var(--accent2)}

/* ═══════ PLAYGROUND ═══════ */
.pg-layout{max-width:1100px;margin:0 auto;padding:1.5rem;display:grid;grid-template-columns:200px 1fr;gap:1.5rem;align-items:start}
.pg-sidebar-title{font-size:11px;font-family:var(--mono);color:var(--text3);text-transform:uppercase;letter-spacing:.08em;margin-bottom:.75rem}
.pg-nav{display:flex;flex-direction:column;gap:4px}
.pg-nav-btn{display:flex;align-items:center;gap:8px;padding:10px 12px;border-radius:var(--r);border:0.5px solid transparent;background:transparent;color:var(--text2);font-size:13px;font-family:var(--sans);cursor:pointer;text-align:left;width:100%;min-height:44px;transition:all .15s}
.pg-nav-btn:hover{background:var(--bg2);color:var(--text)}
.pg-nav-btn.active{background:var(--accent-bg);color:var(--accent2);border-color:rgba(124,111,247,.3)}
.pg-nav-icon{font-size:16px}
.pg-scene-title{font-size:20px;font-weight:600;letter-spacing:-.02em;margin-bottom:4px}
.pg-scene-sub{font-size:13px;color:var(--text2);margin-bottom:1rem}

/* CODE BLOCK */
.code-block{background:var(--bg2);border:0.5px solid var(--border);border-radius:var(--r);padding:1rem 1.25rem;font-family:var(--mono);font-size:13px;line-height:1.7;color:var(--text);margin-bottom:1rem;overflow-x:auto;white-space:pre;-webkit-overflow-scrolling:touch}

/* STAGE */
.stage{background:var(--bg2);border:0.5px solid var(--border);border-radius:var(--r-lg);padding:1.25rem;margin-bottom:1rem;min-height:100px}
.stage-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;min-height:44px;margin-bottom:6px}
.stage-label{font-size:11px;font-family:var(--mono);color:var(--text3);min-width:48px;flex-shrink:0}
.item{display:inline-flex;flex-direction:column;align-items:center;justify-content:center;min-width:56px;height:48px;border-radius:var(--r);border:0.5px solid var(--border2);background:var(--bg3);font-size:12px;padding:0 8px;transition:all .35s cubic-bezier(.34,1.56,.64,1);cursor:default}
.item .iname{font-weight:500;font-size:12px;color:var(--text);white-space:nowrap}
.item .isub{font-size:10px;color:var(--text3);white-space:nowrap;font-family:var(--mono)}
.item.highlight{background:var(--accent-bg);border-color:rgba(124,111,247,.4)}
.item.highlight .iname{color:var(--accent2)}
.item.added{background:var(--green-bg);border-color:rgba(34,201,138,.4)}
.item.added .iname{color:var(--teal)}
.item.result{background:var(--teal-bg);border-color:rgba(56,217,192,.35)}
.item.result .iname{color:var(--teal)}
.item.dim{opacity:.25}
.item.fail{background:var(--red-bg);border-color:rgba(240,84,84,.4)}
.item.fail .iname{color:var(--red)}
.item.pop-in{animation:popIn .4s cubic-bezier(.34,1.56,.64,1) both}
@keyframes popIn{from{opacity:0;transform:scale(0.5)}to{opacity:1;transform:scale(1)}}

.explanation{font-size:14px;color:var(--text);line-height:1.65;padding:12px 16px;background:var(--accent-bg);border-radius:var(--r);border-left:2px solid var(--accent);margin-bottom:.75rem}
.result-output{font-family:var(--mono);font-size:12px;color:var(--text2);padding:4px 0;margin-bottom:1rem}
.progress-bar{height:2px;background:var(--border);border-radius:2px;margin-bottom:1.25rem;overflow:hidden}
.progress-fill{height:100%;background:var(--accent);border-radius:2px;transition:width .3s ease}
.total-badge{display:inline-flex;align-items:center;gap:8px;background:var(--green-bg);border:0.5px solid rgba(34,201,138,.35);border-radius:var(--r);padding:8px 16px;margin-top:8px;font-size:14px;font-weight:500;color:var(--teal);font-family:var(--mono)}

/* STEP CONTROLS */
.step-controls{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-top:4px}
.step-btn{padding:12px 20px;font-size:14px;font-family:var(--sans);cursor:pointer;border-radius:var(--r);border:0.5px solid var(--border2);background:var(--bg2);color:var(--text);transition:all .15s;min-height:48px;min-width:80px;font-weight:500}
.step-btn:hover:not(:disabled){background:var(--bg3);border-color:var(--accent);color:var(--accent2)}
.step-btn:disabled{opacity:.3;cursor:default}
.step-pill{font-size:12px;font-family:var(--mono);color:var(--text3);background:var(--bg3);padding:4px 10px;border-radius:99px}
.step-name{font-size:13px;color:var(--text2)}

/* ═══════ REFERENCE ═══════ */
.ref-layout{max-width:900px;margin:0 auto;padding:1.5rem 1.5rem 4rem}
.ref-title{font-size:2rem;font-weight:600;letter-spacing:-.02em;margin-bottom:.5rem}
.ref-sub{font-size:15px;color:var(--text2);margin-bottom:1.5rem}
.search-wrap{position:relative;margin-bottom:1.25rem}
.search-wrap input{width:100%;padding:12px 14px 12px 40px;background:var(--bg2);border:0.5px solid var(--border2);border-radius:var(--r);color:var(--text);font-size:16px;font-family:var(--sans);outline:none;transition:border-color .15s;-webkit-appearance:none}
.search-wrap input:focus{border-color:var(--accent)}
.search-icon{position:absolute;left:14px;top:50%;transform:translateY(-50%);color:var(--text3);font-size:16px;pointer-events:none}
.ref-filters{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:1.25rem}
.ref-pill{padding:8px 14px;border-radius:99px;border:0.5px solid var(--border2);font-size:12px;font-family:var(--mono);cursor:pointer;background:transparent;color:var(--text2);transition:all .15s;min-height:36px;-webkit-appearance:none}
.ref-pill.active{background:var(--accent-bg);color:var(--accent2);border-color:rgba(124,111,247,.4)}
.ref-count{font-size:13px;color:var(--text3);font-family:var(--mono);margin-bottom:1rem}
.method-card{background:var(--bg2);border:0.5px solid var(--border);border-radius:var(--r-lg);margin-bottom:8px;overflow:hidden}
.method-header{display:flex;align-items:center;gap:10px;padding:14px 16px;cursor:pointer;user-select:none;transition:background .15s;min-height:52px}
.method-header:hover{background:var(--bg3)}
.method-name{font-family:var(--mono);font-size:13px;font-weight:500;color:var(--text);flex-shrink:0}
.method-badge{font-size:11px;font-family:var(--mono);padding:2px 8px;border-radius:5px;flex-shrink:0}
.method-badge.mutates{background:var(--red-bg);color:var(--red)}
.method-badge.copy{background:var(--green-bg);color:var(--teal)}
.method-badge.iter{background:var(--accent-bg);color:var(--accent2)}
.method-badge.search{background:var(--amber-bg);color:var(--amber)}
.method-badge.static{background:var(--teal-bg);color:var(--teal)}
.method-badge.other{background:var(--bg3);color:var(--text2)}
.method-summary{font-size:13px;color:var(--text2);flex:1;min-width:0}
.method-chevron{font-size:13px;color:var(--text3);transition:transform .2s;flex-shrink:0}
.method-chevron.open{transform:rotate(180deg)}
.method-body{padding:0 16px 16px;border-top:0.5px solid var(--border)}
.method-desc{font-size:14px;color:var(--text2);line-height:1.65;margin:12px 0 10px}
.method-example{font-family:var(--mono);font-size:12px;background:var(--bg3);border:0.5px solid var(--border);border-radius:var(--r);padding:10px 14px;line-height:1.7;color:var(--text);white-space:pre;overflow-x:auto;margin-bottom:8px;-webkit-overflow-scrolling:touch}
.method-tip{font-size:12px;color:var(--accent);font-style:italic}

/* ═══════ RESPONSIVE — MODULE PAGES ═══════ */
/* Playground — sidebar stacks on top */
@media(max-width:780px){
  .pg-layout{grid-template-columns:1fr;padding:1rem;gap:1rem}
  .pg-sidebar{position:static !important}
  .pg-nav{flex-direction:row;flex-wrap:wrap;gap:6px}
  .pg-nav-btn{width:auto;flex:0 0 auto;padding:8px 12px;font-size:12px;min-height:40px}
}
@media(max-width:480px){
  .pg-scene-title{font-size:16px}
  .code-block{font-size:11px;padding:.75rem}
  .step-btn{min-height:48px;padding:10px 16px;font-size:13px}
  .step-name{font-size:11px;width:100%;margin-top:4px}
  .item{min-width:48px;height:44px;padding:0 5px}
  .item .iname{font-size:11px}
  .item .isub{font-size:9px}
  .explanation{font-size:13px;padding:10px 12px}
}

/* Reference — full width on mobile */
@media(max-width:680px){
  .ref-layout{padding:1rem 1rem 3rem}
  .ref-title{font-size:1.5rem}
  .method-header{padding:12px;min-height:48px;flex-wrap:wrap}
  .method-badge{display:none}
  .method-summary{font-size:12px;width:100%;margin-top:2px}
  .method-example{font-size:11px;padding:8px 10px}
  .tag-group{flex-direction:column;gap:.5rem}
  .tag-group-label{min-width:unset;text-align:left}
  .scenario-grid{grid-template-columns:1fr 1fr}
  .sc-desc{display:none}
  .hero{padding:2rem 1rem}
  .hero-title{font-size:1.9rem}
  .hero-code{display:none}
  .scenarios-section,.methods-preview{padding:2rem 1rem}
}
@media(max-width:480px){
  .nav-links{display:none}
  .nav-inner{padding:0 1rem;height:50px}
  .scenario-grid{grid-template-columns:1fr 1fr;gap:8px}
  .scenario-card{padding:1rem}
}

/* Touch — bigger tap targets, no hover transforms */
@media(hover:none){
  .scenario-card:hover{transform:none}
  .method-header:hover{background:transparent}
  .step-btn:hover:not(:disabled){background:var(--bg2);border-color:var(--border2);color:var(--text)}
  .pg-nav-btn:hover{background:transparent;color:var(--text2)}
}

/* ═══════ DOM GUIDE — LIVE PREVIEW LAYOUT ═══════ */
.dom-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1rem;
}
.dom-code-side, .dom-preview-side {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.dom-side-label {
  font-size: 11px;
  font-family: var(--mono);
  color: var(--text3);
  text-transform: uppercase;
  letter-spacing: .08em;
}
/* Mini browser window */
.dom-preview {
  background: var(--bg2);
  border: 0.5px solid var(--border2);
  border-radius: var(--r-lg);
  overflow: hidden;
  flex: 1;
}
.dom-preview-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  background: var(--bg3);
  border-bottom: 0.5px solid var(--border);
}
.dom-dots {
  display: flex;
  gap: 4px;
}
.dom-dots span {
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--text3);
  opacity: .5;
}
.dom-dots span:nth-child(1) { background: #ff5f57; opacity: 1; }
.dom-dots span:nth-child(2) { background: #febc2e; opacity: 1; }
.dom-dots span:nth-child(3) { background: #28c840; opacity: 1; }
.dom-url {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text3);
  background: var(--bg4);
  padding: 3px 10px;
  border-radius: 4px;
  flex: 1;
}
.dom-preview-body {
  padding: 1rem;
  min-height: 140px;
}
/* Override code-block for DOM — it doesn't need min-height */
.dom-code-side .code-block {
  flex: 1;
  margin-bottom: 0;
  min-height: 140px;
}

/* Mobile — stack preview below code */
@media (max-width: 680px) {
  .dom-layout {
    grid-template-columns: 1fr;
  }
  .dom-preview-body {
    min-height: 100px;
  }
}