:root{--bg:#0d0f14;--bg2:#12151c;--surface:#171b24;--border:#252b38;--text:#e8eaf0;--muted:#8b93a7;--accent:#f6a62b;--accent2:#4fc3f7;--good:#4ade80;--bad:#f87171;--board:#fbfaf5}
*{box-sizing:border-box}
html,body{height:100%;margin:0;background:var(--bg);color:var(--text);font-family:'DM Sans',system-ui,sans-serif;overflow:hidden}
.hidden{display:none!important}
.bar{height:52px;display:flex;align-items:center;gap:.5rem;padding:0 .8rem;border-bottom:1px solid var(--border);background:var(--bg2)}
.brand{font:800 1.15rem 'Syne',sans-serif;color:var(--text);text-decoration:none;white-space:nowrap}
.hint{color:var(--muted);font-size:.85rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.spacer{flex:1}
.btn,.bar select{background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:9px;padding:.42rem .7rem;font:600 .85rem 'DM Sans',sans-serif;cursor:pointer;white-space:nowrap}
.btn:hover{border-color:var(--accent)} .btn.primary{background:var(--accent);color:#14110a;border-color:var(--accent)}
.btn.on{background:rgba(246,166,43,.15);border-color:var(--accent)}
.app{height:calc(100% - 52px);display:grid;grid-template-columns:minmax(0,1fr) var(--side-w,430px)}
.board{position:relative;min-width:0;background:var(--board);overflow:hidden}
#wb{position:absolute;inset:0;width:100%;height:100%;touch-action:none;cursor:default}
.tools{position:absolute;left:12px;top:12px;z-index:3;display:flex;gap:.3rem;background:#fff;border:2px solid #1f2937;border-radius:12px;padding:.3rem;box-shadow:3px 3px 0 #1f2937}
.tools button{border:0;background:transparent;font:600 .9rem 'DM Sans',sans-serif;color:#1f2937;padding:.35rem .6rem;border-radius:8px;cursor:pointer}
.tools button.on{background:#1f2937;color:#fff}
.tools button:disabled{opacity:.35;cursor:not-allowed}
.tools .tsep{width:1px;background:#cbd5e1;margin:0 .2rem}
.banner{position:absolute;left:50%;top:12px;transform:translateX(-50%);z-index:4;background:#1f2937;color:#fff;border-radius:12px;padding:.55rem 1rem;font:600 1rem 'DM Sans',sans-serif;box-shadow:0 6px 18px rgba(0,0,0,.3);max-width:70%;text-align:center}
.banner .btn{margin-left:.6rem}
.tip{position:absolute;left:12px;bottom:10px;right:12px;z-index:3;color:#475569;font:1.05rem 'Patrick Hand',cursive;pointer-events:none}
.side{position:relative;display:flex;flex-direction:column;min-height:0;border-left:1px solid var(--border);background:var(--bg2)}
.pane{display:flex;flex-direction:column;min-height:0}
.ph{display:flex;justify-content:space-between;align-items:center;padding:.4rem .7rem;color:var(--muted);font-size:.8rem;border-bottom:1px solid var(--border)}
.ph b{color:var(--text);font-weight:700}
.status{font-size:.78rem}.status.err{color:var(--bad)}.status.ok{color:var(--good)}
.codepane{flex:1.2}
.editor{flex:1;display:flex;min-height:0;overflow:auto;background:#0b0d12;font:13.5px/1.55 'DM Mono',monospace}
.gutter{margin:0;padding:.5rem .4rem .5rem .6rem;color:#4b5563;text-align:right;user-select:none;min-width:2.6em}
.edwrap{position:relative;flex:1;min-width:0}
.edwrap .hl,.edwrap textarea{margin:0;padding:.5rem .6rem;font:inherit;white-space:pre;tab-size:4;border:0;width:100%;min-height:100%}
.edwrap .hl{position:absolute;inset:0;pointer-events:none;color:transparent}
.edwrap .hl .cur{background:rgba(246,166,43,.22);box-shadow:inset 3px 0 0 var(--accent);display:inline-block;width:100%}
.edwrap .hl .nxt{background:rgba(79,195,247,.14);display:inline-block;width:100%}
.edwrap .hl .bad{background:rgba(248,113,113,.25);display:inline-block;width:100%}
.edwrap textarea{position:relative;background:transparent;color:#e5e7eb;outline:none;resize:none;overflow:hidden;caret-color:var(--accent);height:auto}
.edwrap textarea[readonly]{caret-color:transparent}
.stepper{display:flex;align-items:center;gap:.3rem;padding:.45rem .6rem;border-top:1px solid var(--border);border-bottom:1px solid var(--border)}
.stepper button{background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:8px;padding:.3rem .5rem;cursor:pointer;font-size:.9rem}
.stepper button:disabled{opacity:.4}
.stepper input{flex:1;accent-color:var(--accent)}
.stepinfo{padding:.35rem .7rem;font-size:.82rem;color:var(--muted);min-height:1.8em}
.stepinfo b{color:var(--text)}
.memory{flex:1;border-top:1px solid var(--border)}
.memory .ph b{flex:1}
.mem{flex:1;display:grid;grid-template-columns:1fr 1fr;gap:.5rem;padding:.5rem;overflow:auto;font:12.5px 'DM Mono',monospace}
.frame{border:1px solid var(--border);border-radius:8px;margin-bottom:.4rem;background:var(--surface)}
.frame.top{border-color:var(--accent)}
.frame .fn{padding:.2rem .45rem;border-bottom:1px solid var(--border);color:var(--accent);font-weight:500}
.frame table,.hobj table{width:100%;border-collapse:collapse}
.frame td,.hobj td{padding:.15rem .45rem;border-bottom:1px solid rgba(255,255,255,.04);vertical-align:top}
.frame td:first-child,.hobj td:first-child{color:var(--muted);width:42%;word-break:break-word}
.chg{background:rgba(250,204,21,.18)}
.ptr{color:var(--accent2)} .nul{color:#64748b} .unk{color:#64748b}
.hobj{border:1px solid var(--border);border-radius:8px;margin-bottom:.4rem;background:var(--surface)}
.hobj .hh{padding:.2rem .45rem;border-bottom:1px solid var(--border);color:#c4b5fd}
.hobj.freed{opacity:.45;text-decoration:line-through}
.hobj.leak{border-color:var(--bad)}
.io{display:grid;grid-template-columns:1fr 1fr;border-top:1px solid var(--border);height:120px}
.io .pane+.pane{border-left:1px solid var(--border)}
.io textarea,.io pre{flex:1;margin:0;background:#0b0d12;color:#e5e7eb;border:0;padding:.4rem .6rem;font:12.5px 'DM Mono',monospace;resize:none;overflow:auto;white-space:pre-wrap}
.modal{position:fixed;inset:0;z-index:50;background:rgba(0,0,0,.55);display:grid;place-items:center}
.modal .card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:1.1rem 1.2rem;width:min(92vw,380px);display:flex;flex-direction:column;gap:.6rem}
.modal h2{margin:0;font:800 1.2rem 'Syne',sans-serif}
.modal label{display:flex;flex-direction:column;gap:.25rem;font-size:.85rem;color:var(--muted)}
.modal input,.modal select{background:var(--bg2);color:var(--text);border:1px solid var(--border);border-radius:8px;padding:.45rem .55rem;font:14px 'DM Mono',monospace}
.modal .row{display:flex;justify-content:flex-end;gap:.5rem;margin-top:.3rem}
.dnote{margin:0;font-size:.8rem;color:var(--muted)}
.livecode{font:800 3rem 'DM Mono',monospace;letter-spacing:.2em;color:var(--accent);text-align:center}
.guesses{max-height:180px;overflow:auto;font-size:.9rem;display:flex;flex-direction:column;gap:.25rem}
.guesses div{background:var(--bg2);border-radius:8px;padding:.3rem .5rem}
body.viewer .tools,body.viewer #predBtn,body.viewer #exSel,body.viewer #shareBtn{display:none}
@media (max-width:900px){.app{grid-template-columns:1fr;grid-template-rows:55% 45%}.side{border-left:0;border-top:1px solid var(--border)}.io{height:90px}}

.scanshot{width:100%;max-height:200px;object-fit:contain;border-radius:10px;border:1px solid var(--border);background:#000}
.scancode{margin:0;max-height:260px;overflow:auto;background:#0b0d12;border:1px solid var(--border);border-radius:10px;padding:.6rem;font:12.5px/1.5 'DM Mono',monospace;white-space:pre}
.spin{display:inline-block;width:1em;height:1em;border:2px solid var(--muted);border-top-color:var(--accent);border-radius:50%;animation:sp .8s linear infinite;vertical-align:-2px;margin-right:.4rem}@keyframes sp{to{transform:rotate(360deg)}}
body.viewer #photoBtn{display:none}

/* resizable panels: drag the edges, double-click to reset */
.split{flex:none;position:relative;z-index:6;touch-action:none}
.split.h{height:9px;margin:-4px 0;cursor:row-resize}
.split.v{position:absolute;left:-5px;top:0;bottom:0;width:10px;cursor:col-resize}
.split::after{content:'';position:absolute;background:var(--accent);opacity:0;transition:opacity .15s;border-radius:2px}
.split.h::after{left:0;right:0;top:3px;height:3px}.split.v::after{top:0;bottom:0;left:3px;width:3px}
.split:hover::after,.split.on::after{opacity:.8}
body.resizing{user-select:none;-webkit-user-select:none}body.resizing.col{cursor:col-resize}body.resizing.row{cursor:row-resize}
/* files your program reads (ifstream) and writes (ofstream) */
.filebar{display:flex;flex-wrap:wrap;align-items:center;gap:.35rem;padding:.35rem .6rem;border-top:1px solid var(--border);font-size:.78rem;color:var(--muted)}
.filebar:empty{display:none}
.fchip{display:inline-flex;align-items:center;gap:.25rem;background:var(--surface);border:1px solid var(--border);border-radius:999px;padding:.12rem .25rem .12rem .6rem;color:var(--text);font:12px 'DM Mono',monospace;max-width:220px}
.fchip span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.fchip button,.fchip a{background:none;border:0;color:var(--muted);cursor:pointer;font-size:.9rem;padding:0 .3rem;text-decoration:none}
.fchip button:hover,.fchip a:hover{color:var(--accent)}
.fchip.out{border-color:rgba(74,222,128,.45)}
.fadd{background:none;border:1px dashed var(--border);border-radius:999px;color:var(--muted);padding:.12rem .6rem;cursor:pointer;font:600 .76rem 'DM Sans',sans-serif}
.fadd:hover{color:var(--accent);border-color:var(--accent)}
.dropzone{position:fixed;inset:0;z-index:60;background:rgba(13,15,20,.82);display:grid;place-items:center;pointer-events:none}
.dropzone div{border:3px dashed var(--accent);border-radius:20px;padding:2.2rem 3rem;text-align:center;font:700 1.3rem 'DM Sans',sans-serif;color:var(--text);line-height:1.6;background:rgba(23,27,36,.9)}
.dropzone small{font-weight:500;font-size:.95rem;color:var(--muted)}
body.viewer #openBtn,body.viewer .split,body.viewer .fadd,body.viewer .fchip button{display:none}
@media (max-width:900px){.split.v{display:none}}
.stepper select{background:var(--surface);color:var(--text);border:1px solid var(--border);border-radius:8px;padding:.28rem .2rem;font:600 .78rem 'DM Sans',sans-serif;cursor:pointer}
.stepper #playBtn{white-space:nowrap;font-weight:700}.stepper #playBtn.on{background:rgba(246,166,43,.18);border-color:var(--accent)}
.tools button#treeBtn.on{background:#dcfce7;color:#166534}
body.viewer #playBtn,body.viewer #speedSel,body.viewer #treeBtn{display:none}