:root {
  --bg: #070a07;
  --bg-soft: #0c120c;
  --panel: #0a0f0a;
  --line: #16241a;
  --line-bright: #1f3a26;
  --fg: #b9f5c6;
  --fg-dim: #5f7a64;
  --accent: #39ff6a;
  --accent-soft: #1f7a3a;
  --easy: #3fd6a0;
  --med: #e8c14a;
  --hard: #ff5d6c;
  --mono: "JetBrains Mono", "SF Mono", "Cascadia Code", Menlo, Consolas, "Liberation Mono", monospace;
  --glow: 0 0 6px rgba(57, 255, 106, 0.35);
}
body.amber {
  --bg: #0a0700; --bg-soft: #120d02; --panel: #0d0900;
  --line: #2a1d05; --line-bright: #3d2b08;
  --fg: #ffd089; --fg-dim: #8a6b3a; --accent: #ffb627; --accent-soft: #8a5e10;
  --easy: #d6c43f; --med: #ff9e3d; --hard: #ff5d6c;
  --glow: 0 0 6px rgba(255, 182, 39, 0.35);
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.5;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}
#scanlines {
  position: fixed; inset: 0; pointer-events: none; z-index: 9999;
  background: repeating-linear-gradient(0deg, rgba(0,0,0,0.18) 0 1px, transparent 1px 3px);
  mix-blend-mode: multiply;
}
::selection { background: var(--accent); color: var(--bg); }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
button {
  font-family: var(--mono); font-size: 12px; cursor: pointer;
  background: transparent; color: var(--fg);
  border: 1px solid var(--line-bright); padding: 3px 9px; border-radius: 2px;
}
button:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); box-shadow: var(--glow); }
button:disabled { opacity: 0.4; cursor: default; }
button.active { background: var(--accent); color: var(--bg); border-color: var(--accent); }

.admin-gate {
  position: fixed; inset: 0; z-index: 10000; display: grid; place-items: center;
  background: rgba(7, 10, 7, .92); padding: 18px;
}
.admin-gate[hidden] { display: none; }
.admin-card {
  width: min(360px, 100%); border: 1px solid var(--line-bright); background: var(--bg-soft);
  padding: 16px; box-shadow: 0 0 0 1px var(--bg), var(--glow);
}
.admin-title { color: var(--accent); font-weight: 700; margin-bottom: 12px; }
.admin-card label { display: block; color: var(--fg-dim); font-size: 11px; margin: 10px 0 3px; text-transform: uppercase; }
.admin-card input {
  width: 100%; background: var(--panel); color: var(--fg); border: 1px solid var(--line-bright);
  padding: 7px 8px; font: inherit; outline: none;
}
.admin-card input:focus { border-color: var(--accent); box-shadow: var(--glow); }
.admin-card button { width: 100%; margin-top: 14px; padding: 7px 8px; }
.admin-error { min-height: 18px; margin-top: 9px; color: var(--hard); font-size: 11px; }

#app { display: flex; flex-direction: column; height: 100%; }

/* topbar */
#topbar {
  display: flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-bottom: 1px solid var(--line);
  background: var(--bg-soft); flex: 0 0 auto; white-space: nowrap;
}
#topbar .prompt { color: var(--accent); text-shadow: var(--glow); }
#topbar .sep { color: var(--fg-dim); }
#topbar .path { color: var(--fg); }
#topbar .cursor { color: var(--accent); animation: blink 1.05s steps(1) infinite; margin-left: 1px; }
@keyframes blink { 50% { opacity: 0; } }
#topbar .spacer { flex: 1; }
#setbar { display: flex; gap: 4px; margin-right: 8px; }

#bottom-meta {
  flex: 0 0 auto; display: flex; align-items: center; justify-content: flex-end; gap: 10px;
  padding: 4px 12px; border-top: 1px solid var(--line);
  background: #070b07; color: var(--fg-dim); font-size: 10.5px; white-space: nowrap;
}
#bottom-meta .build, #bottom-meta .version { color: var(--fg-dim); letter-spacing: 0.3px; }
#bottom-meta .version { color: var(--accent); }
.bottom-links { display: flex; gap: 9px; flex-wrap: wrap; justify-content: flex-end; }
.bottom-links a { color: var(--fg-dim); }
.bottom-links a:hover, .bottom-links a:focus-visible { color: var(--accent); text-decoration: underline; }

/* main split */
#main { flex: 1; display: flex; min-height: 0; }
#graph-pane { flex: 1; display: flex; flex-direction: column; min-width: 0; border-right: 1px solid var(--line); }
#graph-scroll { flex: 1; overflow: auto; padding: 24px; }
#graph-scroll::-webkit-scrollbar, #side-body::-webkit-scrollbar, #ws-verdict::-webkit-scrollbar, #ws-stmt-body::-webkit-scrollbar { width: 9px; height: 9px; }
#graph-scroll::-webkit-scrollbar-thumb, #side-body::-webkit-scrollbar-thumb, #ws-verdict::-webkit-scrollbar-thumb, #ws-stmt-body::-webkit-scrollbar-thumb { background: var(--line-bright); }
#graph-scroll::-webkit-scrollbar-track, #side-body::-webkit-scrollbar-track, #ws-verdict::-webkit-scrollbar-track, #ws-stmt-body::-webkit-scrollbar-track { background: transparent; }
svg#graph { display: block; }

/* edges + nodes (svg) */
.edge { fill: none; stroke: var(--line-bright); stroke-width: 1.4; }
.edge.lit { stroke: var(--accent); stroke-width: 1.8; filter: drop-shadow(0 0 3px var(--accent)); }
.node { cursor: pointer; }
.node rect {
  fill: var(--panel); stroke: var(--line-bright); stroke-width: 1.4;
  transition: stroke 0.12s, fill 0.12s;
}
.node .nm { fill: var(--fg); font: 600 11px var(--mono); }
.node .ct { fill: var(--fg-dim); font: 11px var(--mono); }
.node .bar-bg { fill: var(--line); }
.node .bar-fg { fill: var(--accent-soft); }
.node:hover rect { stroke: var(--accent); }
.node:hover .nm { fill: var(--accent); }
.node.sel rect { fill: #0e1a10; stroke: var(--accent); stroke-width: 2; }
.node.sel .nm { fill: var(--accent); }
.node.done rect { stroke: var(--accent); }
.node.done .bar-fg { fill: var(--accent); }
.node .corner { fill: var(--accent); }
.node.dim rect { stroke: var(--line); }
.node.dim .nm { fill: var(--fg-dim); }

#legend {
  flex: 0 0 auto; display: flex; gap: 16px; align-items: center;
  padding: 6px 14px; border-top: 1px solid var(--line); color: var(--fg-dim); font-size: 11px;
}
#legend .dot { display: inline-block; width: 8px; height: 8px; border-radius: 50%; margin-right: 5px; vertical-align: middle; }
.dot.easy { background: var(--easy); } .dot.med { background: var(--med); } .dot.hard { background: var(--hard); }
.muted { color: var(--fg-dim); }
#legend .spacer { flex: 1; }
.credit { color: #3a4a3d; font-size: 10.5px; }
.credit a { color: #4f6a54; }
.credit a:hover { color: var(--accent); }

/* side pane */
#side-pane { flex: 0 0 50%; display: flex; flex-direction: column; min-width: 0; background: var(--bg-soft); }
#side-head { flex: 0 0 auto; padding: 8px 12px 6px; border-bottom: 1px solid var(--line); }
#side-head .cmd { color: var(--accent); }
#side-head .cmd::before { content: "$ "; color: var(--fg-dim); }
#side-head .sub { color: var(--fg-dim); font-size: 11px; margin-top: 2px; }
#side-body { flex: 1; overflow: auto; padding: 6px 0 24px; }
.welcome pre { color: var(--fg-dim); padding: 10px 14px; font-size: 12px; white-space: pre-wrap; }
.welcome pre, #side-body pre { margin: 0; }

/* problem rows */
.grp { padding: 8px 0 4px; }
.grp .grp-h { color: var(--fg-dim); font-size: 11px; padding: 4px 14px; text-transform: lowercase; }
ul.plist { list-style: none; margin: 0; padding: 0; }
ul.plist li {
  display: flex; align-items: baseline; gap: 8px;
  padding: 4px 14px; border-left: 2px solid transparent;
}
ul.plist li:hover { background: #0e150e; border-left-color: var(--accent); }
ul.plist li.done .pname { color: var(--fg-dim); text-decoration: line-through; }
.chk {
  flex: 0 0 auto; width: 14px; height: 14px; line-height: 12px; text-align: center;
  border: 1px solid var(--line-bright); color: var(--accent); cursor: pointer;
  font-size: 11px; border-radius: 2px; user-select: none;
}
.chk:hover { border-color: var(--accent); }
li.done .chk { background: var(--accent); color: var(--bg); border-color: var(--accent); }
.pname { flex: 1; min-width: 0; }
.pname a { color: var(--fg); }
.pname a:hover { color: var(--accent); }
li.done .pname a { color: var(--fg-dim); }
.diff { flex: 0 0 auto; font-size: 10px; letter-spacing: 0.5px; padding: 1px 5px; border-radius: 2px; border: 1px solid; }
.diff.Easy { color: var(--easy); border-color: var(--easy); }
.diff.Medium { color: var(--med); border-color: var(--med); }
.diff.Hard { color: var(--hard); border-color: var(--hard); }
.lc { flex: 0 0 auto; color: var(--fg-dim); font-size: 11px; }
.lc:hover { color: var(--accent); }

.summary { padding: 8px 14px; color: var(--fg-dim); font-size: 11px; border-bottom: 1px solid var(--line); }
.summary b { color: var(--accent); }

/* ---------- problem-row solve link ---------- */
.psolve { flex: 0 0 auto; color: var(--fg-dim); font-size: 11px; cursor: pointer; text-decoration: none; }
.psolve:hover { color: var(--accent); }
.psolve.has { color: var(--accent); }
.psolve.has::before { content: "‹/›"; }       /* curated: in-browser judge + bundled sample tests */
.psolve.ed { color: var(--fg-dim); opacity: 0.85; }
.psolve.ed::before { content: "‹/›"; }        /* editor-only: open in-browser, no bundled tests yet */
/* every problem name opens the in-browser editor on click */
.pn-open { cursor: pointer; color: var(--accent) !important; }
.pn-open:hover { text-decoration: underline; }
li.hasws .pname::after { content: "‹/›"; color: var(--fg-dim); font-size: 9px; margin-left: 6px; vertical-align: 1px; }

/* ---------- workspace (kotlin judge) ---------- */
#workspace { flex: 1; display: flex; flex-direction: column; min-height: 0; }
#workspace[hidden] { display: none; }
#ws-bar {
  display: flex; align-items: center; gap: 8px; white-space: nowrap;
  padding: 6px 12px; border-bottom: 1px solid var(--line); background: var(--bg-soft); flex: 0 0 auto;
}
#ws-bar .spacer { flex: 1; }
.ws-crumb { color: var(--fg); }
.ws-crumb .b { color: var(--fg-dim); }
.ws-diff { font-size: 10px; padding: 1px 5px; border: 1px solid; border-radius: 2px; }
.ws-diff.Easy { color: var(--easy); border-color: var(--easy); }
.ws-diff.Medium { color: var(--med); border-color: var(--med); }
.ws-diff.Hard { color: var(--hard); border-color: var(--hard); }
.ws-lc { color: var(--fg-dim); font-size: 11px; }
.ws-lc:hover { color: var(--accent); }
.lang-pill { color: var(--accent); border: 1px solid var(--accent-soft); border-radius: 2px; padding: 1px 6px; font-size: 11px; }
#ws-status { font-size: 11px; color: var(--fg-dim); }
#ws-status.ok { color: var(--easy); } #ws-status.bad { color: var(--hard); } #ws-status.run { color: var(--med); }
.markbtn { font-size: 11px; }
.markbtn.done { background: var(--accent); color: var(--bg); border-color: var(--accent); }

#ws-body { flex: 1; display: flex; min-height: 0; }
#ws-stmt { flex: 0 0 44%; display: flex; flex-direction: column; min-width: 220px; border-right: 1px solid var(--line); }
#ws-tabs { flex: 0 0 auto; display: flex; gap: 2px; align-items: center; padding: 5px 8px; border-bottom: 1px solid var(--line); background: var(--bg-soft); }
#ws-tabs .spacer { flex: 1; }
.tab { font-size: 11px; border-color: transparent; color: var(--fg-dim); }
.tab:hover { color: var(--accent); border-color: transparent; box-shadow: none; }
.tab.active { color: var(--accent); border-bottom: 1px solid var(--accent); border-radius: 0; }
#ws-stmt-body { flex: 1; overflow: auto; padding: 14px 18px 28px; }

#ws-drag { flex: 0 0 5px; cursor: col-resize; background: var(--line); }
#ws-drag:hover { background: var(--accent-soft); }

#ws-edit { flex: 1; display: flex; flex-direction: column; min-width: 0; }
#ws-editor { flex: 1; min-height: 120px; }
#ws-io { flex: 0 0 200px; min-height: 0; display: flex; border-top: 1px solid var(--line); }
#ws-io .io-col { flex: 1; display: flex; flex-direction: column; min-width: 0; min-height: 0; padding: 6px 8px; gap: 4px; }
#ws-io .io-col + .io-col { border-left: 1px solid var(--line); }
#ws-io label { font-size: 11px; color: var(--fg-dim); }
#ws-io textarea {
  flex: 1; resize: none; background: var(--panel); color: var(--fg); border: 1px solid var(--line);
  font-family: var(--mono); font-size: 12px; padding: 6px; border-radius: 2px;
}
#ws-io textarea:focus { outline: none; border-color: var(--accent-soft); }
#ws-verdict { flex: 1; min-height: 0; overflow-y: scroll; overflow-x: hidden; font-size: 12px; scrollbar-gutter: stable; }
.tc { border: 1px solid var(--line); border-left-width: 3px; border-radius: 2px; margin: 4px 0; padding: 5px 8px; }
.tc.pass { border-left-color: var(--easy); }
.tc.fail { border-left-color: var(--hard); }
.tc.err  { border-left-color: var(--med); }
.tc .tch { font-weight: 600; }
.tc.pass .tch { color: var(--easy); } .tc.fail .tch { color: var(--hard); } .tc.err .tch { color: var(--med); }
.tc pre { margin: 3px 0 0; white-space: pre-wrap; word-break: break-word; color: var(--fg-dim); font-size: 11px; }
.tc pre b { color: var(--fg); }

/* markdown rendering inside statement / editorial */
#ws-stmt-body h1, #ws-stmt-body h2, #ws-stmt-body h3 { color: var(--accent); font-size: 13px; margin: 14px 0 6px; text-transform: lowercase; }
#ws-stmt-body p, #ws-stmt-body li { color: var(--fg); }
#ws-stmt-body code { background: #0f1a10; border: 1px solid var(--line); border-radius: 2px; padding: 0 3px; color: var(--accent); }
#ws-stmt-body pre { background: var(--panel); border: 1px solid var(--line); border-radius: 2px; padding: 8px; overflow: auto; }
#ws-stmt-body pre code { border: none; background: none; color: var(--fg); }
#ws-stmt-body hr { border: none; border-top: 1px solid var(--line); }
#ws-stmt-body a { color: var(--accent); }
#ws-stmt-body ul, #ws-stmt-body ol { padding-left: 20px; }
#ws-stmt-body .meta { color: var(--fg-dim); font-size: 11px; }
#ws-stmt-body .empty { color: var(--fg-dim); }

.policy-page {
  flex: 1;
  min-height: 100vh;
  overflow: auto;
  padding: 48px min(6vw, 56px);
  background: var(--bg);
}
.policy-body {
  min-height: 100%;
  overflow: auto;
  display: flex;
  flex-direction: column;
}
.policy-body .policy-page {
  min-height: 0;
}
.policy-shell { max-width: 840px; margin: 0 auto; }
.policy-kicker { color: var(--fg-dim); font-size: 12px; margin: 0 0 8px; }
.policy-page h1 { color: var(--accent); margin: 0 0 8px; font-size: clamp(28px, 5vw, 52px); line-height: 1.05; text-shadow: var(--glow); }
.policy-page h2 { color: var(--accent); margin: 28px 0 8px; font-size: 14px; text-transform: uppercase; letter-spacing: .04em; }
.policy-page p, .policy-page li { color: var(--fg); }
.policy-card { border: 1px solid var(--line-bright); background: var(--bg-soft); padding: 18px; margin: 16px 0; }

/* ---------- always-on command line ---------- */
#cli {
  flex: 0 0 168px; display: flex; flex-direction: column; min-height: 0;
  border-top: 1px solid var(--line-bright); background: #060906;
  font-size: 12.5px;
}
body.cli-min #cli { flex-basis: 26px; }
body.cli-min #cli-log { display: none; }
#cli-log { flex: 1; overflow-y: auto; padding: 6px 10px 2px; white-space: pre-wrap; word-break: break-word; }
#cli-log .ln { color: var(--fg); }
#cli-log .cmd-echo { color: var(--accent); }
#cli-log .cmd-echo::before { content: "grind:" attr(data-cwd) "$ "; color: var(--fg-dim); }
#cli-log .err { color: var(--hard); }
#cli-log .ok { color: var(--easy); }
#cli-log .dim { color: var(--fg-dim); }
#cli-log .hl { color: var(--accent); }
#cli-line { flex: 0 0 auto; display: flex; align-items: center; gap: 7px; padding: 4px 10px; border-top: 1px solid var(--line); background: #080c08; }
#cli-ps1 { color: var(--fg-dim); white-space: nowrap; }
#cli-ps1 b { color: var(--accent); }
#cli-in {
  flex: 1; background: transparent; border: none; outline: none; color: var(--fg);
  font-family: var(--mono); font-size: 12.5px; padding: 2px 0; caret-color: var(--accent);
}
#cli-in::placeholder { color: #324034; }
#cli-toggle { color: var(--fg-dim); cursor: pointer; user-select: none; padding: 0 2px; }
#cli-toggle:hover { color: var(--accent); }
body.cli-min #cli-toggle { transform: rotate(180deg); }

@media (max-width: 820px) {
  body { overflow: auto; }
  #main { flex-direction: column; }
  #topbar { flex-wrap: wrap; }
  #bottom-meta { justify-content: flex-start; flex-wrap: wrap; row-gap: 2px; }
  .bottom-links { justify-content: flex-start; }
  #side-pane { flex: none; width: 100%; border-top: 1px solid var(--line); }
  #graph-pane { border-right: none; }
  #ws-body { flex-direction: column; }
  #ws-stmt { flex: none; height: 40vh; border-right: none; border-bottom: 1px solid var(--line); }
  #ws-drag { display: none; }
  #ws-editor { min-height: 240px; }
  #cli { flex-basis: 120px; }
}

/* --- flashcard + stats (androidprep) --- */
#card { flex: 1; min-height: 0; display: flex; flex-direction: column; padding: 8px 12px 12px; }
#card[hidden] { display: none; }
#card-scroll { flex: 1; min-height: 0; overflow: auto; padding-right: 4px; }
#card-q { font-size: 15px; line-height: 1.5; overflow-wrap: anywhere; word-break: break-word; }
#card-reveal { margin: 12px 0; }
#card-answer { margin-top: 6px; overflow-wrap: anywhere; word-break: break-word; }
#card-answer h3 { margin: 14px 0 4px; text-transform: lowercase; opacity: .8; }
#card-answer ul { padding-left: 18px; }
.fu-list { display: flex; flex-direction: column; gap: 4px; }
.fu { border: 1px solid var(--line); border-radius: 3px; padding: 6px 9px; background: var(--bg); }
.fu.fu-plain { color: var(--fg-dim); }
.fu > summary { cursor: pointer; list-style: none; color: var(--fg); padding-left: 2px; }
.fu > summary::-webkit-details-marker { display: none; }
.fu > summary::before { content: "▶"; display: inline-block; width: 1.1em; color: var(--accent, #39ff6a); font-size: 0.8em; transition: transform 0.12s ease; }
.fu[open] > summary::before { content: "▼"; }
.fu > summary:hover { color: var(--accent, #39ff6a); }
.fu[open] > summary { color: var(--accent, #39ff6a); margin-bottom: 6px; }
.fu .fu-a { color: var(--fg-dim); font-size: 13px; line-height: 1.5; overflow-wrap: anywhere; }
.fu .fu-a p:first-child { margin-top: 0; }
#card-q pre, #card-answer pre { white-space: pre-wrap; word-break: break-word; overflow-x: auto; }
#card-q code, #card-answer code { overflow-wrap: anywhere; word-break: break-word; }
#card .row { flex: 0 0 auto; display: flex; align-items: center; gap: 8px; margin-top: 10px; padding-top: 10px; border-top: 1px solid var(--line); }
#card .row .spacer { flex: 1; }
#card button { cursor: pointer; }
#card-known { color: var(--accent, #39ff6a); }
li.review > .chk { color: var(--amber, #ffb627); }
#stats-panel { margin: 12px; border: 1px solid var(--edge, #1f8f3f); padding: 10px; }
#stats-panel .stats-head { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
#stats-panel .spacer { flex: 1; }
#stats-body pre { white-space: pre-wrap; word-break: break-word; }