/* "Escalate or Clear?" challenge */
.ch-app { min-height: 70vh; }
.ch-loading { padding: 120px 24px; text-align: center; color: var(--slate); }
.ch-wrap { max-width: 760px; margin: 0 auto; padding: 40px 20px 72px; }
.ch-hero { position: relative; overflow: hidden; background-color: #0A0A0F; background-image: radial-gradient(ellipse 60% 70% at 12% 0%, rgba(124,58,237,0.34) 0%, transparent 60%), radial-gradient(ellipse 50% 60% at 95% 100%, rgba(236,72,153,0.24) 0%, transparent 60%); color: #F4F3F8; padding: 76px 20px 64px; text-align: center; }
.ch-hero-inner { position: relative; z-index: 1; max-width: 720px; margin: 0 auto; }
.ch-hero h1 { font-weight: 900; font-size: clamp(40px, 8vw, 72px); line-height: 0.98; letter-spacing: -0.045em; margin: 14px 0 18px; }
.ch-hero h1 .esc { color: #FB7185; }
.ch-hero h1 .clr { color: #34D399; }
.ch-hero p { color: #B8B5CA; font-size: 17px; max-width: 560px; margin: 0 auto; }
.ch-tag { display: inline-flex; align-items: center; gap: 8px; font-size: 12px; font-weight: 700; letter-spacing: 0.16em; color: #C4B5FD; padding: 6px 14px; border: 1px solid rgba(196,181,253,0.28); border-radius: 999px; background: rgba(124,58,237,0.12); }
.ch-cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 30px; }
.ch-btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font: inherit; font-weight: 700; font-size: 15px; padding: 13px 22px; border-radius: 12px; border: 1px solid transparent; cursor: pointer; text-decoration: none; transition: filter .15s, transform .15s, border-color .15s; }
.ch-btn:active { transform: translateY(1px); }
.ch-btn.primary { background: var(--gradient); color: #fff; box-shadow: 0 12px 28px -12px rgba(124,58,237,0.75); }
.ch-btn.primary:hover { filter: brightness(1.08); }
.ch-btn.ghost { background: var(--card-2); color: var(--ink); border-color: var(--rule); }
.ch-btn.ghost:hover { border-color: var(--accent); }
.ch-hero .ch-btn.ghost { background: rgba(255,255,255,0.05); color: #F4F3F8; border-color: rgba(255,255,255,0.18); }
.ch-btn[disabled] { opacity: .5; cursor: not-allowed; }
.ch-steps { display: grid; gap: 14px; grid-template-columns: 1fr; margin-top: 8px; }
@media (min-width: 720px) { .ch-steps { grid-template-columns: repeat(3, 1fr); } }
.ch-step { background: var(--card); border: 1px solid var(--rule); border-radius: 16px; padding: 20px; }
.ch-step b { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 9px; background: var(--accent-soft); color: var(--accent); font-size: 14px; margin-bottom: 10px; }
.ch-step h3 { font-size: 16.5px; font-weight: 700; letter-spacing: -0.01em; margin-bottom: 4px; }
.ch-step p { color: var(--slate); font-size: 14.5px; }
.ch-h2 { font-weight: 800; font-size: clamp(22px, 3.2vw, 28px); letter-spacing: -0.025em; line-height: 1.2; margin: 44px 0 14px; }
.ch-segs { display: flex; flex-wrap: wrap; gap: 8px; }
.ch-segs span { font-size: 13px; font-weight: 600; border: 1px solid var(--rule); background: var(--card-2); border-radius: 999px; padding: 5px 12px; }

/* panels and forms */
.ch-panel { background: var(--card); border: 1px solid var(--rule); border-radius: 18px; padding: 24px 22px; box-shadow: var(--shadow); }
.ch-kicker { font-size: 11.5px; font-weight: 700; letter-spacing: 0.14em; color: var(--accent); }
.ch-title { font-weight: 800; font-size: clamp(24px, 4.4vw, 34px); line-height: 1.12; letter-spacing: -0.03em; margin: 6px 0 8px; text-wrap: balance; }
.ch-sub { color: var(--slate); font-size: 15px; }
.ch-meta { display: flex; flex-wrap: wrap; gap: 8px 18px; margin: 16px 0 4px; font-size: 14px; color: var(--slate); }
.ch-meta b { color: var(--ink); }
.ch-beat { margin: 16px 0 6px; padding: 14px 16px; border-radius: 14px; background: var(--accent-soft); border: 1px solid rgba(167,139,250,0.35); font-weight: 600; }
.ch-field { margin-top: 16px; }
.ch-field label { display: block; font-size: 12.5px; font-weight: 600; letter-spacing: 0.03em; color: var(--slate); margin-bottom: 6px; }
.ch-field input { width: 100%; font: inherit; font-size: 16px; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--rule); background: var(--bg); color: var(--ink); }
.ch-field input:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.ch-hint { font-size: 12.5px; color: var(--slate); margin-top: 6px; }
.ch-err { color: #FB7185; font-size: 14px; margin-top: 10px; min-height: 1px; }
.ch-rules { margin: 18px 0 4px; padding-left: 18px; color: var(--slate); font-size: 14px; }
.ch-rules li { margin: 3px 0; }
.ch-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }

/* case picker */
.ch-pick-head { position: sticky; top: 64px; z-index: 5; display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 12px 14px; margin: 18px 0 10px; border-radius: 14px; background: var(--card-2); border: 1px solid var(--rule); }
.ch-pick-head b { font-size: 15px; }
.ch-seg-title { font-size: 12px; font-weight: 700; letter-spacing: 0.12em; color: var(--slate); margin: 18px 0 8px; text-transform: uppercase; }
.ch-pick { width: 100%; text-align: left; display: flex; align-items: center; gap: 12px; font: inherit; color: var(--ink); background: var(--card); border: 1px solid var(--rule); border-radius: 14px; padding: 12px 14px; margin-bottom: 8px; cursor: pointer; }
.ch-pick:hover { border-color: rgba(167,139,250,0.5); }
.ch-pick .box { flex-shrink: 0; width: 22px; height: 22px; border-radius: 7px; border: 2px solid var(--rule); display: grid; place-items: center; }
.ch-pick.on { border-color: var(--accent); background: var(--accent-soft); }
.ch-pick.on .box { background: var(--gradient); border-color: transparent; }
.ch-pick.on .box::after { content: ""; width: 9px; height: 5px; border-left: 2.5px solid #fff; border-bottom: 2.5px solid #fff; transform: rotate(-45deg) translate(1px, -1px); }
.ch-pick .pt { font-weight: 650; font-size: 15px; }
.ch-pick .pm { font-size: 12.5px; color: var(--slate); }
.lvl { font-size: 11px; font-weight: 700; letter-spacing: .06em; padding: 2px 8px; border-radius: 999px; margin-left: auto; flex-shrink: 0; }
.lvl.Easy { color: #34D399; background: rgba(52,211,153,.12); }
.lvl.Medium { color: #FBBF24; background: rgba(251,191,36,.12); }
.lvl.Hard { color: #FB7185; background: rgba(251,113,133,.12); }

/* playing */
.ch-top { position: sticky; top: 56px; z-index: 6; background: var(--bg); padding: 12px 0 10px; }
.ch-prog { display: flex; align-items: center; justify-content: space-between; font-size: 13.5px; font-weight: 600; color: var(--slate); margin-bottom: 8px; }
.ch-prog .clock { font-variant-numeric: tabular-nums; color: var(--ink); font-weight: 700; }
.ch-prog .clock.low { color: #FB7185; }
.ch-dots { display: flex; gap: 6px; }
.ch-dots i { width: 22px; height: 6px; border-radius: 4px; background: var(--rule); }
.ch-dots i.ok { background: #34D399; } .ch-dots i.no { background: #FB7185; } .ch-dots i.cur { background: var(--accent); }
.ch-bar { height: 6px; border-radius: 6px; background: var(--rule); overflow: hidden; }
.ch-bar span { display: block; height: 100%; width: 100%; background: var(--gradient); transform-origin: left; transition: transform 1s linear; }
.ch-bar.low span { background: #FB7185; }
.case-head { margin-top: 14px; }
.case-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 8px; }
.case-tags span { font-size: 11.5px; font-weight: 700; letter-spacing: .05em; padding: 3px 9px; border-radius: 999px; background: var(--card-2); border: 1px solid var(--rule); color: var(--slate); }
.case-title { font-size: clamp(22px, 4vw, 28px); font-weight: 800; letter-spacing: -0.025em; line-height: 1.15; }
.case-file { margin-top: 14px; display: flex; flex-direction: column; gap: 10px; }
.cf { background: var(--card); border: 1px solid var(--rule); border-radius: 14px; overflow: hidden; }
.cf-p { padding: 14px 16px; font-size: 15px; }
.cf-prof { display: grid; grid-template-columns: minmax(110px, 34%) 1fr; }
.cf-prof div { padding: 9px 14px; font-size: 14.5px; border-top: 1px solid var(--rule); }
.cf-prof div:nth-child(-n+2) { border-top: none; }
.cf-prof .k { color: var(--slate); font-size: 12.5px; font-weight: 600; letter-spacing: .02em; background: var(--card-2); }
.cf-note { padding: 12px 16px; border-left: 3px solid var(--accent); font-size: 14.5px; }
.cf-note b { display: block; font-size: 11.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--accent); margin-bottom: 3px; }
.cf-tbl { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.cf-tbl table { width: 100%; border-collapse: collapse; font-size: 14px; }
.cf-tbl th { text-align: left; font-size: 11.5px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--slate); background: var(--card-2); padding: 9px 12px; white-space: nowrap; }
.cf-tbl td { padding: 9px 12px; border-top: 1px solid var(--rule); vertical-align: top; }
.cf-tbl td:last-child { font-variant-numeric: tabular-nums; }
.cf-tbl.wide table { min-width: 0; }
.case-q { margin: 20px 0 10px; font-size: 18px; font-weight: 750; letter-spacing: -0.01em; }
.opts { display: flex; flex-direction: column; gap: 10px; }
.opt { display: flex; gap: 12px; align-items: flex-start; text-align: left; width: 100%; font: inherit; font-size: 15px; line-height: 1.5; color: var(--ink); background: var(--card); border: 1.5px solid var(--rule); border-radius: 14px; padding: 14px 16px; cursor: pointer; transition: border-color .15s, background .15s; }
.opt:hover:not([disabled]) { border-color: var(--accent); }
.opt .L { flex-shrink: 0; width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center; font-weight: 800; font-size: 14px; background: var(--card-2); border: 1px solid var(--rule); }
.opt[disabled] { cursor: default; }
.opt.sel { border-color: var(--accent); background: var(--accent-soft); }
.opt.right { border-color: #34D399; background: rgba(52,211,153,.10); }
.opt.right .L { background: #34D399; color: #062016; border-color: transparent; }
.opt.wrong { border-color: #FB7185; background: rgba(251,113,133,.10); }
.opt.wrong .L { background: #FB7185; color: #2A0610; border-color: transparent; }
.opt.dim { opacity: .55; }
.fb { margin-top: 16px; border-radius: 16px; padding: 18px; border: 1px solid var(--rule); background: var(--card-2); }
.fb-h { font-size: 20px; font-weight: 800; letter-spacing: -0.02em; }
.fb-h.ok { color: #34D399; } .fb-h.no { color: #FB7185; }
.fb p { margin-top: 8px; font-size: 15px; }
.fb .clue { color: var(--slate); font-size: 14px; }
.fb a { color: var(--accent); font-weight: 600; text-decoration: none; }
.fb .next { margin-top: 14px; }

/* results */
.res-card { text-align: center; padding: 30px 20px; border-radius: 22px; color: #F4F3F8; background-color: #0E0D15; background-image: radial-gradient(ellipse 70% 80% at 15% 0%, rgba(124,58,237,0.45) 0%, transparent 60%), radial-gradient(ellipse 60% 70% at 95% 100%, rgba(236,72,153,0.32) 0%, transparent 60%); border: 1px solid rgba(255,255,255,0.08); }
.res-card .big { font-size: clamp(54px, 13vw, 88px); font-weight: 900; letter-spacing: -0.05em; line-height: 1; margin-top: 8px; }
.res-card .big small { font-size: .42em; color: #A3A0B6; letter-spacing: -0.02em; }
.res-card .rt { display: inline-block; margin-top: 12px; font-size: 15px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; padding: 7px 16px; border-radius: 999px; background: var(--gradient); }
.res-card .rs { margin-top: 14px; color: #C9C6D8; font-size: 15px; }
.res-share { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-top: 18px; }
.bd { width: 100%; border-collapse: collapse; font-size: 14.5px; }
.bd th { text-align: left; font-size: 11.5px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--slate); padding: 8px 10px; border-bottom: 1px solid var(--rule); }
.bd td { padding: 11px 10px; border-bottom: 1px solid var(--rule); font-variant-numeric: tabular-nums; }
.bd td.n { font-weight: 650; word-break: break-word; }
.bd .c { color: #34D399; font-weight: 700; } .bd .w { color: #FB7185; font-weight: 700; }
.bd tr.me td { background: var(--accent-soft); }
.bd .badge { display: inline-block; white-space: nowrap; font-size: 10.5px; font-weight: 700; letter-spacing: .08em; padding: 2px 7px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); margin-left: 6px; vertical-align: 2px; }
.bd .medal { display: inline-grid; place-items: center; width: 24px; height: 24px; border-radius: 50%; font-size: 12px; font-weight: 800; background: var(--card-2); }
.bd tr:nth-child(1) .medal { background: #FBBF24; color: #3A2A00; }
.bd tr:nth-child(2) .medal { background: #D1D5DB; color: #1F2937; }
.bd tr:nth-child(3) .medal { background: #F59E0B; color: #3A1E00; opacity: .85; }
.rv { margin-top: 12px; border: 1px solid var(--rule); border-radius: 14px; background: var(--card); overflow: hidden; }
.rv summary { list-style: none; cursor: pointer; display: flex; align-items: center; gap: 10px; padding: 14px 16px; font-weight: 700; }
.rv summary::-webkit-details-marker { display: none; }
.rv summary .ic { flex-shrink: 0; width: 24px; height: 24px; border-radius: 50%; display: grid; place-items: center; font-size: 13px; font-weight: 900; }
.rv summary .ic.ok { background: #34D399; color: #062016; } .rv summary .ic.no { background: #FB7185; color: #2A0610; }
.rv summary .chev { margin-left: auto; color: var(--slate); transition: transform .2s; }
.rv[open] summary .chev { transform: rotate(180deg); }
.rv-body { padding: 0 16px 16px; font-size: 14.5px; }
.rv-body .why { margin-top: 8px; }
.rv-body .why div { padding: 8px 0; border-top: 1px solid var(--rule); }
.rv-body .why b { display: inline-block; min-width: 22px; }
.rv-body .why .is-ans b { color: #34D399; }
.rv-body a { color: var(--accent); font-weight: 600; text-decoration: none; }
.ch-make { margin-top: 34px; text-align: center; padding: 26px 20px; border-radius: 18px; border: 1px dashed rgba(167,139,250,0.5); background: var(--accent-soft); }
.ch-make h3 { font-size: 21px; font-weight: 800; letter-spacing: -0.02em; }
.ch-make p { color: var(--slate); margin: 6px 0 14px; }
.ch-toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); background: #17151F; color: #F4F3F8; border: 1px solid rgba(255,255,255,0.12); padding: 10px 16px; border-radius: 12px; font-size: 14px; z-index: 300; box-shadow: 0 18px 40px -16px rgba(0,0,0,.7); }
.ch-link { display: flex; gap: 8px; margin-top: 14px; }
.ch-link input { flex: 1; min-width: 0; font: inherit; font-size: 15px; padding: 11px 12px; border-radius: 12px; border: 1px solid var(--rule); background: var(--bg); color: var(--ink); }
@media (max-width: 520px) { .ch-wrap { padding: 28px 16px 60px; } .ch-panel { padding: 20px 16px; } .opt { padding: 12px 13px; font-size: 14.5px; } .cf-prof { grid-template-columns: 1fr; } .cf-prof div:nth-child(2) { border-top: none; } .cf-prof .k { padding-bottom: 2px; border-top: 1px solid var(--rule); } .cf-prof div:first-child { border-top: none; } .cf-prof div:not(.k) { border-top: none; padding-top: 2px; } .bd .hide-sm { display: none; } }

@media (max-width: 520px) { .cf-tbl th, .cf-tbl td { padding: 8px 9px; font-size: 13px; } .cf-tbl th { white-space: normal; } .bd .badge { display: table; margin: 3px 0 0; } .ch-top { top: 50px; } }