/* ===== 폰트 (컨테이너 내장 / 오프라인 동작) ===== */
@font-face {
  font-family: "Pretendard Variable";
  font-weight: 45 920;
  font-style: normal;
  font-display: swap;
  src: url("fonts/PretendardVariable.woff2") format("woff2-variations");
}
@font-face {
  font-family: "JetBrains Mono";
  font-weight: 400; font-style: normal; font-display: swap;
  src: url("fonts/JetBrainsMono-400.woff2") format("woff2");
}
@font-face {
  font-family: "JetBrains Mono";
  font-weight: 700; font-style: normal; font-display: swap;
  src: url("fonts/JetBrainsMono-700.woff2") format("woff2");
}

:root {
  --bg: #fbfbfd;
  --surface: #ffffff;
  --line: #ececf0;
  --line-strong: #e0e0e6;
  --ink: #18181b;
  --ink-2: #3f3f46;
  --muted: #8b8b94;
  --accent: #4f46e5;
  --accent-dark: #4338ca;
  --accent-soft: #eef2ff;
  --ok: #16a34a; --ok-soft: #ecfdf3;
  --bad: #dc2626; --bad-soft: #fef2f2;

  /* 에디터(다크) */
  --ed-bg: #1e1e1e;
  --ed-tab: #252526;
  --ed-line: #2d2d2d;
  --ed-text: #d4d4d4;
  --ed-gutter: #858585;
  --tok-kw: #c586c0;
  --tok-fn: #dcdcaa;
  --tok-str: #ce9178;
  --tok-num: #b5cea8;
  --tok-cmt: #6a9955;
  --tok-const: #569cd6;
  --blank: #ffe28a;
  --blank-focus: #ffd54a;

  --sans: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont, system-ui, "Malgun Gothic", sans-serif;
  --mono: "JetBrains Mono", "Cascadia Code", Consolas, "D2Coding", monospace;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--ink);
  font-size: 16px; line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  letter-spacing: -0.01em;
}

/* ===== 상단 바 ===== */
.topbar {
  display: flex; align-items: center; gap: 14px;
  height: 60px; padding: 0 18px;
  background: rgba(255,255,255,.85);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 10;
}
.icon-btn {
  display: grid; place-items: center;
  width: 38px; height: 38px; border-radius: 10px;
  background: transparent; border: 1px solid transparent; color: var(--ink-2);
  cursor: pointer; transition: background .15s, border-color .15s;
}
.icon-btn:hover { background: #f4f4f6; border-color: var(--line); }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; }
.brand-mark {
  width: 22px; height: 22px; border-radius: 7px;
  background: linear-gradient(135deg, #6366f1, #4f46e5 60%, #7c3aed);
  box-shadow: 0 2px 6px rgba(79,70,229,.35);
}
.brand-sub { color: var(--muted); font-weight: 600; }

/* ===== 레이아웃 ===== */
.layout { display: flex; height: calc(100vh - 60px); }

/* ===== 사이드바 ===== */
.sidebar {
  width: 286px; flex-shrink: 0;
  background: var(--surface);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  transition: width .22s ease, opacity .18s ease;
}
.sidebar.collapsed { width: 0; opacity: 0; overflow: hidden; border: none; }
.sidebar-head {
  padding: 20px 20px 10px; color: var(--muted);
  font-size: 12px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase;
}
.tree { padding: 0 12px 24px; }
.tree-empty { color: var(--muted); padding: 10px; font-size: 14px; white-space: pre-line; }

.tree-leaf {
  display: flex; align-items: center; gap: 9px; width: 100%; text-align: left;
  background: none; border: none; cursor: pointer;
  padding: 9px 11px; border-radius: 9px; margin: 1px 0;
  color: var(--ink-2); font-size: 14.5px; font-family: var(--sans); font-weight: 500;
  transition: background .13s, color .13s;
}
.tree-leaf:hover { background: #f5f5f7; color: var(--ink); }
.tree-leaf.active { background: var(--accent-soft); color: var(--accent-dark); font-weight: 600; }
.tree-leaf svg { flex-shrink: 0; color: var(--muted); }
.tree-leaf.active svg { color: var(--accent); }
.tree-leaf.scratch { color: var(--accent-dark); font-weight: 600; margin-bottom: 8px; }
.tree-leaf.scratch svg { color: var(--accent); }

.folder { margin-top: 4px; }
.folder-head {
  display: flex; align-items: center; gap: 7px; width: 100%;
  background: none; border: none; cursor: pointer;
  padding: 9px 8px; border-radius: 9px;
  font-size: 13.5px; font-weight: 700; color: var(--ink);
  font-family: var(--sans); letter-spacing: -0.01em;
}
.folder-head:hover { background: #f5f5f7; }
.folder-head .caret { color: var(--muted); transition: transform .15s ease; }
.folder.open .folder-head .caret { transform: rotate(90deg); }
.folder-head .folder-ico { color: var(--muted); }
.folder-body { margin-left: 12px; padding-left: 8px; border-left: 1px solid var(--line); overflow: hidden; }
.folder-body.collapsed { display: none; }

/* ===== 메인 ===== */
.main { flex: 1; overflow-y: auto; padding: 32px; }
.main > section { max-width: 940px; margin: 0 auto; }

.panel {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: 16px; padding: 28px;
}
.hidden { display: none !important; }

.welcome h2 { margin: 0 0 12px; font-size: 22px; letter-spacing: -0.02em; }
.welcome p { color: var(--ink-2); margin: 8px 0; }
.blank-demo {
  background: var(--blank); color: #5b4a00; font-weight: 700;
  padding: 1px 8px; border-radius: 5px; font-family: var(--mono); font-size: .9em;
}

.head { margin-bottom: 18px; }
#pTitle { margin: 0 0 6px; font-size: 23px; letter-spacing: -0.02em; }
.desc { color: var(--ink-2); margin: 0; font-size: 15.5px; }

code { background: #f0f0f3; padding: 1.5px 6px; border-radius: 5px; font-family: var(--mono); font-size: .88em; }

/* ===== VSCode 스타일 에디터 ===== */
.code {
  border-radius: 14px; overflow: hidden; background: var(--ed-bg);
  border: 1px solid #2a2a2a;
  box-shadow: 0 12px 34px rgba(15,15,20,.16);
  margin-bottom: 16px;
}
.code-tab {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 16px; background: var(--ed-tab); color: #cccccc;
  font: 600 13px var(--mono); border-bottom: 1px solid #1a1a1a;
}
.code-tab svg { color: #6a9fd4; }
.code-body { display: flex; max-height: 60vh; overflow: auto; }
.gutter {
  flex-shrink: 0; padding: 16px 0; text-align: right;
  color: var(--ed-gutter); background: var(--ed-bg);
  font: 400 16px/1.7 var(--mono); user-select: none;
  min-width: 52px; overflow: hidden;
}
.gutter span { display: block; padding: 0 14px 0 12px; }
.code-area {
  flex: 1; padding: 16px 18px;
  font: 400 16px/1.7 var(--mono); color: var(--ed-text);
  white-space: pre; tab-size: 4;
}
/* 문법 색상 */
.tok-kw   { color: var(--tok-kw); }
.tok-fn   { color: var(--tok-fn); }
.tok-str  { color: var(--tok-str); }
.tok-num  { color: var(--tok-num); }
.tok-cmt  { color: var(--tok-cmt); font-style: italic; }
.tok-const{ color: var(--tok-const); }

/* 채우는 빈칸 */
.blank-input {
  font: 700 16px var(--mono);
  background: var(--blank); color: #4a3c00;
  border: none; border-radius: 6px;
  padding: 1px 8px; margin: 0 3px; outline: none;
  box-shadow: inset 0 0 0 1px rgba(0,0,0,.06);
  transition: background .12s, box-shadow .12s;
  vertical-align: baseline;
}
.blank-input::placeholder { color: #9a8410; font-weight: 600; }
.blank-input:focus { background: var(--blank-focus); box-shadow: 0 0 0 3px rgba(255,200,40,.35); }

/* 처음부터 작성 모드 — textarea 위에 하이라이트 레이어를 겹쳐 VSCode처럼 */
.code-area.scratch-mode { padding: 0; position: relative; }
.scratch-wrap { position: relative; height: 340px; }
.hl-layer, .scratch-area {
  margin: 0; border: 0; padding: 16px 18px;
  font: 400 16px/1.7 var(--mono); tab-size: 4;
  white-space: pre; word-wrap: normal; letter-spacing: 0;
}
.hl-layer {
  position: absolute; inset: 0; overflow: hidden;
  color: var(--ed-text); pointer-events: none;
}
.scratch-area {
  position: absolute; inset: 0; width: 100%; height: 100%;
  background: transparent; color: transparent; caret-color: #ffffff;
  resize: none; outline: none; overflow: auto;
}
.scratch-area::selection { background: rgba(120,150,255,.35); }

/* ===== 입력 필드 ===== */
.field { margin: 16px 0; }
.field label { display: block; font-weight: 700; font-size: 14px; margin-bottom: 7px; }
.muted-label { font-weight: 500; color: var(--muted); font-size: 13px; }
.field textarea {
  width: 100%; font: 400 15px var(--mono); color: var(--ink);
  background: var(--surface); border: 1px solid var(--line-strong);
  border-radius: 10px; padding: 11px 13px; resize: vertical;
  transition: border-color .13s, box-shadow .13s;
}
.field textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }

/* ===== 버튼 ===== */
.actions { display: flex; align-items: center; gap: 10px; margin: 18px 0 14px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--sans); font-size: 15px; font-weight: 600;
  border: 1px solid transparent; border-radius: 11px; padding: 11px 20px; cursor: pointer;
  transition: background .14s, border-color .14s, transform .06s, box-shadow .14s;
}
.btn:active { transform: translateY(1px); }
.btn-run { background: var(--accent); color: #fff; box-shadow: 0 4px 14px rgba(79,70,229,.32); }
.btn-run:hover { background: var(--accent-dark); }
.btn-run:disabled { background: #c7c7d1; box-shadow: none; cursor: default; }
.btn-ghost { background: var(--surface); color: var(--ink-2); border-color: var(--line-strong); }
.btn-ghost:hover { background: #f5f5f7; }
.status { color: var(--muted); font-size: 14px; }

.kbd {
  font: 600 11.5px var(--mono); line-height: 1;
  background: rgba(255,255,255,.22); color: #fff;
  padding: 3px 7px; border-radius: 6px; margin-left: 4px;
  border: 1px solid rgba(255,255,255,.18);
}

/* 스크롤해도 항상 보이는 실행 버튼 */
.fab {
  position: fixed; right: 28px; bottom: 28px; z-index: 30;
  display: inline-flex; align-items: center; gap: 9px;
  background: var(--accent); color: #fff; border: none;
  border-radius: 16px; padding: 15px 24px; cursor: pointer;
  font: 600 15.5px var(--sans);
  box-shadow: 0 12px 32px rgba(79,70,229,.42);
  transition: background .14s, transform .08s, box-shadow .14s;
  animation: fabIn .18s ease;
}
.fab:hover { background: var(--accent-dark); box-shadow: 0 14px 36px rgba(79,70,229,.5); }
.fab:active { transform: translateY(1px); }
@keyframes fabIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

/* ===== 결과 ===== */
.result-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 9px 15px; border-radius: 10px; font-weight: 600; font-size: 14.5px;
  margin-bottom: 14px; border: 1px solid transparent;
}
.result-badge.ok  { background: var(--ok-soft);  color: var(--ok);  border-color: #bbf7d0; }
.result-badge.bad { background: var(--bad-soft); color: var(--bad); border-color: #fecaca; }

/* ===== 정답 보기 ===== */
.answer-wrap { margin-bottom: 14px; }
.btn-answer { font-size: 14px; padding: 9px 16px; }
.answer-box {
  margin-top: 12px; border-radius: 14px; overflow: hidden;
  border: 1px solid #2a2a2a; background: var(--ed-bg);
  box-shadow: 0 8px 24px rgba(15,15,20,.12);
}
.answer-head {
  padding: 9px 16px; background: var(--ed-tab); color: #cccccc;
  font: 600 12px var(--mono); letter-spacing: .06em; text-transform: uppercase;
  border-bottom: 1px solid #161616;
}
.answer-code {
  margin: 0; padding: 16px 18px; overflow-x: auto;
  font: 400 15.5px/1.7 var(--mono); color: var(--ed-text); white-space: pre; tab-size: 4;
}

.terminal { border-radius: 14px; overflow: hidden; border: 1px solid #2a2a2a; background: #1b1b1b; }
.terminal-head {
  padding: 9px 16px; background: #232323; color: #9a9a9a;
  font: 600 12px var(--mono); letter-spacing: .06em; text-transform: uppercase;
  border-bottom: 1px solid #161616;
}
.output {
  margin: 0; padding: 16px 18px; min-height: 58px;
  font: 400 15px/1.65 var(--mono); color: #e6e6e6;
  white-space: pre-wrap; word-break: break-word;
}
.output .err     { color: #f48771; }
.output .blocked { color: #e2b341; }
.output .muted   { color: #6b6b6b; }

/* ===== 해킹 경고 오버레이 ===== */
.hack-overlay {
  position: fixed; inset: 0; z-index: 9999;
  display: grid; place-items: center; text-align: center;
  animation: strobe .14s steps(1, end) infinite;
}
.hack-inner { display: grid; justify-items: center; gap: 18px; padding: 24px; }
.hack-img {
  width: min(58vw, 340px); border-radius: 14px;
  border: 4px solid #fff; box-shadow: 0 0 40px rgba(255,255,255,.6);
  animation: hackShake .18s linear infinite;
}
.hack-title {
  font-family: var(--sans); font-weight: 900;
  font-size: clamp(34px, 9vw, 92px); line-height: 1; color: #fff;
  text-shadow: 0 0 18px #ff0, 0 0 36px #f00;
  animation: hackBlink .26s steps(1, end) infinite;
  letter-spacing: -0.02em;
}
.hack-sub {
  font-family: var(--sans); font-weight: 700; color: #fff;
  font-size: clamp(15px, 2.6vw, 21px); line-height: 1.5;
  text-shadow: 0 2px 8px rgba(0,0,0,.7);
}
.hack-sub code { background: rgba(0,0,0,.45); color: #ffd54a; }
.hack-close {
  margin-top: 6px; font-family: var(--sans); font-weight: 800; font-size: 16px;
  color: #b00020; background: #fff; border: none; border-radius: 12px;
  padding: 12px 28px; cursor: pointer; box-shadow: 0 6px 20px rgba(0,0,0,.4);
}
.hack-close:hover { background: #ffe28a; }
@keyframes strobe {
  0%   { background: #c1121f; }
  25%  { background: #000; }
  50%  { background: #ff1744; }
  75%  { background: #0a0a0a; }
  100% { background: #e10600; }
}
@keyframes hackBlink { 0%,100% { opacity: 1; } 50% { opacity: .15; color: #ff0; } }
@keyframes hackShake {
  0%   { transform: translate(0,0) rotate(0deg); }
  25%  { transform: translate(-6px,4px) rotate(-2deg); }
  50%  { transform: translate(5px,-5px) rotate(1.5deg); }
  75%  { transform: translate(-4px,-3px) rotate(-1deg); }
  100% { transform: translate(5px,4px) rotate(2deg); }
}

@media (max-width: 720px) {
  .sidebar { position: absolute; z-index: 8; height: calc(100vh - 60px); box-shadow: 6px 0 24px rgba(0,0,0,.12); }
  .main { padding: 18px; }
  .panel { padding: 18px; }
}