:root {
  --navy: #12314f;
  --red: #b4232a;
  --green: #1c7a4a;
  --amber: #b07a12;
  --line: #dfe3e8;
  --bg: #f7f8fa;
  --ink: #1b2733;
  --dim: #667585;
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: 'Pretendard', 'Apple SD Gothic Neo', 'Malgun Gothic', 'Noto Sans KR', sans-serif;
  font-size: 16px; line-height: 1.65;
}
header {
  background: var(--navy); color: #fff; padding: 14px 24px;
  display: flex; align-items: center; gap: 24px; flex-wrap: wrap;
}
header .brand { color: #fff; font-weight: 700; font-size: 18px; text-decoration: none; }
header nav { margin-left: auto; display: flex; gap: 18px; }
header nav a { color: #cfe0f0; text-decoration: none; font-size: 15px; }
header nav a:hover { color: #fff; }
main { max-width: 920px; margin: 0 auto; padding: 28px 24px 60px; }
footer { text-align: center; color: var(--dim); font-size: 13px; padding: 24px; }
h1 { font-size: 26px; margin: 0 0 18px; }
h2 { font-size: 20px; margin: 32px 0 12px; color: var(--navy); }
h3 { font-size: 17px; margin: 24px 0 10px; }
a { color: var(--navy); }
table { width: 100%; border-collapse: collapse; background: #fff; margin: 12px 0 24px; }
th, td { border: 1px solid var(--line); padding: 9px 12px; text-align: left; font-size: 15px; }
th { background: #eef1f5; font-weight: 600; }
td.num { text-align: right; font-variant-numeric: tabular-nums; }
.btn {
  display: inline-block; background: var(--navy); color: #fff; text-decoration: none;
  padding: 7px 14px; border-radius: 5px; font-size: 14px; border: 0; cursor: pointer;
}
.btn.ghost { background: #fff; color: var(--navy); border: 1px solid var(--navy); }
.kind { font-size: 13px; color: var(--dim); }
.crumb { color: var(--dim); font-size: 14px; margin-bottom: 8px; }
.meta { color: var(--dim); font-size: 14px; }
.empty { color: var(--dim); padding: 24px 0; }
.error { background: #fdecec; border: 1px solid #f0b8b8; color: var(--red);
         padding: 10px 14px; border-radius: 5px; }
.problem { background: #fff; border: 1px solid var(--line); border-radius: 6px;
           padding: 20px 24px; }
.problem table { margin: 12px 0; }
.problem pre, pre {
  background: #f2f4f7; border: 1px solid var(--line); border-radius: 5px;
  padding: 10px 12px; overflow-x: auto; font-size: 14px; line-height: 1.5;
  font-family: 'SFMono-Regular', Consolas, 'D2Coding', monospace; white-space: pre-wrap;
}
.problem code { background: #eef1f5; padding: 1px 5px; border-radius: 3px; font-size: 14px; }
.submit-form { background: #fff; border: 1px solid var(--line); border-radius: 6px;
               padding: 20px 24px; margin-top: 20px; }
.submit-form .row { display: flex; gap: 18px; flex-wrap: wrap; }
.submit-form label { display: block; font-size: 14px; color: var(--dim); margin-bottom: 14px; }
.submit-form label.block { display: block; }
.submit-form input[type=text], .submit-form input:not([type]) {
  display: block; margin-top: 4px; padding: 8px 10px; border: 1px solid var(--line);
  border-radius: 5px; font-size: 15px; min-width: 200px;
}
.submit-form input { display: block; margin-top: 4px; padding: 8px 10px;
  border: 1px solid var(--line); border-radius: 5px; font-size: 15px; }
.submit-form textarea {
  display: block; width: 100%; margin-top: 6px; padding: 12px;
  border: 1px solid var(--line); border-radius: 5px; font-size: 14px; line-height: 1.5;
  font-family: 'SFMono-Regular', Consolas, 'D2Coding', monospace; resize: vertical;
}
.submit-form button { background: var(--navy); color: #fff; border: 0; border-radius: 5px;
  padding: 11px 22px; font-size: 16px; cursor: pointer; }
.submit-form button:hover { background: #0d2540; }
.inline-form { display: flex; gap: 12px; align-items: flex-end; margin-bottom: 18px; }
.inline-form input { padding: 8px 10px; border: 1px solid var(--line); border-radius: 5px; }
.inline-form button { background: var(--navy); color: #fff; border: 0; border-radius: 5px;
  padding: 9px 18px; cursor: pointer; }
.verdict { display: flex; align-items: center; gap: 16px; padding: 16px 20px;
  border-radius: 6px; font-size: 18px; margin: 16px 0 24px; }
.verdict strong { font-size: 20px; }
.verdict span { color: inherit; opacity: .85; font-variant-numeric: tabular-nums; }
.verdict.pass { background: #e7f5ed; border: 1px solid #a8d8bf; color: var(--green); }
.verdict.partial { background: #fdf4e3; border: 1px solid #e8cf9a; color: var(--amber); }
.verdict.fail { background: #fdecec; border: 1px solid #f0b8b8; color: var(--red); }
.case { border: 1px solid var(--line); border-radius: 6px; margin-bottom: 14px;
        background: #fff; overflow: hidden; }
.case-head { padding: 9px 14px; font-weight: 600; font-size: 15px; }
.case.ok .case-head { background: #e7f5ed; color: var(--green); }
.case.no .case-head { background: #fdecec; color: var(--red); }
.case-head em { font-weight: 400; font-style: normal; margin-left: 8px; font-size: 14px; }
.case-body { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 14px; padding: 14px; }
.case-body h4 { margin: 0 0 6px; font-size: 13px; color: var(--dim); font-weight: 600; }
.case-body pre { margin: 0; min-height: 44px; }
.chips { display: flex; flex-wrap: wrap; gap: 6px; margin: 10px 0; }
.chip { display: inline-flex; align-items: center; justify-content: center;
  width: 34px; height: 34px; border-radius: 5px; font-size: 14px; font-weight: 600; }
.chip.ok { background: #e7f5ed; color: var(--green); border: 1px solid #a8d8bf; }
.chip.no { background: #fdecec; color: var(--red); border: 1px solid #f0b8b8; }
.tag { padding: 2px 9px; border-radius: 4px; font-size: 14px; }
.tag.pass { background: #e7f5ed; color: var(--green); }
.tag.partial { background: #fdf4e3; color: var(--amber); }
.tag.fail { background: #fdecec; color: var(--red); }
.compiler { color: #7a2020; background: #fdf3f3; border-color: #f0c9c9; }
.compiler.warn { color: #7a5a10; background: #fdf8ea; border-color: #e8d8a8; }
.hint { color: var(--dim); font-size: 14px; }
.who { color: var(--dim); margin-top: -8px; }
.actions { margin-top: 28px; display: flex; gap: 10px; }
.note { margin-top: 36px; background: #fff; border: 1px solid var(--line);
        border-radius: 6px; padding: 16px 22px; }
.note h3 { margin-top: 0; }
.note ol { padding-left: 20px; }
@media (max-width: 700px) {
  .case-body { grid-template-columns: 1fr; }
  main { padding: 20px 14px 48px; }
}