/* ============================================================
   GameJS Academy — design system
   paper & ink editorial base · electric blue + coral accents
   type: Bricolage Grotesque (display) / Inter (text) / JetBrains Mono (code)
   ============================================================ */
:root{
  --paper:#F6F2EA;
  --paper-2:#FFFFFF;
  --ink:#151210;
  --ink-2:#40382F;
  --muted:#7C7267;
  --line:#E6DFD2;
  --line-strong:#D6CCBA;

  --blue:#3346E6;
  --blue-deep:#22319E;
  --coral:#FF5B35;
  --yellow:#FFC93C;
  --mint:#0FBF85;

  --dark:#14141B;
  --dark-2:#1B1B24;
  --dark-line:#2B2B38;
  --dark-text:#E6E6F0;

  --r-sm:8px; --r-md:14px; --r-lg:20px;
  --shadow-sm:0 1px 2px rgba(21,18,16,.07);
  --shadow-md:0 6px 24px rgba(21,18,16,.09);
  --shadow-hard:4px 4px 0 var(--ink);

  --font-display:'Bricolage Grotesque','Inter','MiSans','PingFang SC','Microsoft YaHei','Noto Sans SC',sans-serif;
  --font-text:'Inter','MiSans','PingFang SC','Microsoft YaHei','Noto Sans SC',system-ui,-apple-system,sans-serif;
  --font-mono:'JetBrains Mono',Consolas,'MiSans','PingFang SC','Microsoft YaHei',monospace;

  /* hand-drawn radii (classic wobble trick) */
  --rd-hand:255px 15px 225px 15px/15px 225px 15px 255px;
  --rd-btn:16px 6px 15px 6px/7px 14px 6px 16px;
}

*{box-sizing:border-box}
.svg-defs{position:absolute;width:0;height:0;overflow:hidden}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--paper);color:var(--ink);
  font-family:var(--font-text);font-size:16px;line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3{font-family:var(--font-display);letter-spacing:-.02em;margin:0}
button{font-family:inherit}
code,kbd,.mini-code{font-family:var(--font-mono)}
code{background:#FFF3D6;color:#8A5B00;padding:2px 6px;border-radius:6px;font-size:.88em}
kbd{background:#FFF;border:1px solid var(--line-strong);border-bottom-width:2px;
  border-radius:6px;padding:1px 6px;font-size:.82em;font-family:var(--font-mono);color:var(--ink-2)}

/* ---------------- buttons ---------------- */
.btn{
  border:1.5px solid transparent;border-radius:var(--rd-btn);padding:11px 20px;
  font-size:15px;font-weight:600;letter-spacing:-.01em;cursor:pointer;
  transition:transform .12s ease, box-shadow .12s ease, background .15s;
  white-space:nowrap;
}
.i-play{width:9px;height:11px;vertical-align:-1px;margin-right:3px}
.btn:active{transform:translateY(2px);box-shadow:none!important}
.btn:disabled{opacity:.42;cursor:not-allowed;transform:none;box-shadow:none}
.btn-primary{background:var(--blue);color:#fff;box-shadow:0 4px 0 var(--blue-deep)}
.btn-primary:hover:not(:disabled){background:#3F51F2;box-shadow:0 6px 0 var(--blue-deep);transform:translateY(-1px)}
.btn-success{background:var(--mint);color:#04301F;box-shadow:0 4px 0 #0A8C61}
.btn-success:hover:not(:disabled){background:#14CE92;box-shadow:0 6px 0 #0A8C61;transform:translateY(-1px)}
.btn-ghost{background:var(--paper-2);color:var(--ink);border-color:var(--line-strong);box-shadow:0 2px 0 var(--line-strong)}
.lang-btn{background:transparent;border:1.5px solid var(--line-strong);border-radius:999px;
  font-weight:700;letter-spacing:.02em;box-shadow:none;padding:7px 14px}
.lang-btn:hover{border-color:var(--ink-2);background:var(--paper-2);box-shadow:none;transform:translateY(-1px)}
.lang-zh h1,.lang-zh h2,.lang-zh h3{letter-spacing:0}
.btn-ghost:hover{border-color:var(--ink);box-shadow:0 3px 0 var(--ink)}
.btn-lg{padding:15px 28px;font-size:16.5px;border-radius:14px}
.btn-sm{padding:8px 14px;font-size:13.5px;border-radius:10px}
.btn-block{width:100%;padding:14px;font-size:15.5px}
.btn:focus-visible{outline:3px solid var(--yellow);outline-offset:2px}

/* ---------------- topbar ---------------- */
.topbar{
  position:sticky;top:0;z-index:30;display:flex;justify-content:space-between;
  align-items:center;gap:16px;padding:14px 26px;
  background:rgba(246,242,234,.86);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);
}
.brand{display:flex;align-items:center;gap:10px;cursor:pointer;user-select:none}
.brand-mark{width:30px;height:30px;display:block;filter:url(#rough) drop-shadow(0 2px 4px rgba(51,70,230,.35))}
.brand-name{font-family:var(--font-display);font-weight:800;font-size:19px;letter-spacing:-.03em}
.brand-sub{font-size:13px;font-weight:600;color:var(--muted);margin-left:5px;letter-spacing:.02em}
.topbar-right{display:flex;gap:10px;align-items:center}
.lang-switch{display:flex;gap:3px;align-items:center}
.lang-switch a{font-size:12.5px;font-weight:700;color:var(--muted);text-decoration:none;
  padding:4px 8px;border-radius:9px;border:1.6px solid transparent;letter-spacing:.02em;transition:.14s}
.lang-switch a:hover{color:var(--ink)}
.lang-switch a.on{color:var(--blue);border-color:var(--blue);background:rgba(51,70,230,.07)}
.progress-pill{
  display:flex;align-items:center;gap:8px;background:var(--paper-2);
  border:1.5px solid var(--line-strong);border-radius:var(--rd-hand);padding:6px 15px;
  font-size:13px;font-weight:600;color:var(--ink-2);transform:rotate(-.5deg);
}
.progress-pill .dot{width:7px;height:7px;border-radius:50%;background:var(--mint);
  box-shadow:0 0 0 3px rgba(15,191,133,.18)}

/* ---------------- hero ---------------- */
.hero{
  max-width:1200px;margin:0 auto;padding:76px 26px 70px;
  display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center;
  position:relative;
}
.hero::before{ /* faint dotted grid */
  content:'';position:absolute;inset:0;z-index:-1;pointer-events:none;
  background-image:radial-gradient(rgba(21,18,16,.07) 1px,transparent 1px);
  background-size:26px 26px;
  mask-image:linear-gradient(180deg,#000 0%,transparent 78%);
  -webkit-mask-image:linear-gradient(180deg,#000 0%,transparent 78%);
}
.eyebrow{
  display:inline-block;font-size:12.5px;font-weight:700;letter-spacing:.14em;
  text-transform:uppercase;color:var(--blue);
  background:rgba(51,70,230,.09);border:1.5px solid rgba(51,70,230,.35);
  padding:6px 14px;border-radius:var(--rd-hand);margin-bottom:22px;
  transform:rotate(-.4deg);
}
.hero h1{
  font-size:clamp(38px,5vw,62px);line-height:1.0;font-weight:800;
  letter-spacing:-.035em;margin-bottom:20px;
}
.mark{
  background:linear-gradient(transparent 58%, var(--yellow) 58%, var(--yellow) 94%, transparent 94%);
  padding:0 2px;
}
.lede{font-size:18.5px;color:var(--ink-2);max-width:34em;margin:0 0 30px}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:34px}
.hero-stats{
  list-style:none;display:flex;gap:34px;padding:0;margin:0;
  border-top:1px solid var(--line-strong);padding-top:22px;flex-wrap:wrap;
}
.hero-stats li{display:flex;flex-direction:column;line-height:1.15}
.hero-stats b{font-family:var(--font-display);font-size:27px;font-weight:800;letter-spacing:-.03em}
.hero-stats span{font-size:12.5px;color:var(--muted);font-weight:500;text-transform:uppercase;letter-spacing:.08em}

/* hero demo window */
.window{
  background:var(--dark);border-radius:var(--r-lg);overflow:hidden;
  box-shadow:0 24px 60px rgba(21,18,16,.28), 0 2px 0 rgba(255,255,255,.06) inset;
  border:1px solid #000;
  transform:rotate(-.6deg);
}
.window-bar{
  display:flex;align-items:center;justify-content:space-between;gap:12px;
  background:var(--dark-2);border-bottom:1px solid var(--dark-line);
  padding:11px 14px;
}
.win-dots{display:flex;gap:6px}
.win-dots i{width:10px;height:10px;border-radius:50%;background:#3A3A48;display:block}
.win-dots i:nth-child(1){background:#FF5F57}
.win-dots i:nth-child(2){background:#FEBC2E}
.win-dots i:nth-child(3){background:#28C840}
.win-file{font-family:var(--font-mono);font-size:12.5px;color:#9A9AB0;display:flex;align-items:center;gap:7px}
.js-badge{
  background:#F7DF1E;color:#151210;font-size:9.5px;font-weight:700;
  padding:2px 4px;border-radius:4px;letter-spacing:-.03em;font-style:italic;
}
.win-run{
  background:#1F3F2E;color:#5BE49B;border:1px solid #2C5B44;
  font-family:var(--font-mono);font-size:11.5px;font-weight:700;
  padding:4px 12px;border-radius:7px;
}
.demo-code{
  margin:0;padding:18px 20px;font-family:var(--font-mono);font-size:13px;
  line-height:1.75;color:#D7D7E6;overflow-x:auto;
}
.demo-code .c{color:#61617A}
.demo-code .k{color:#C79BF7}
.demo-code .n{color:#FF9D6C}
.demo-code .f{color:#7FB2FF}
.demo-code .s{color:#8CE99A}
.demo-output{
  position:relative;background:var(--dark-2);border-top:1px solid var(--dark-line);
  padding:14px;display:flex;justify-content:center;
}
.demo-output canvas{border-radius:10px;background:#1C1C26;display:block;max-width:100%}
.output-label{
  position:absolute;top:10px;left:14px;font-family:var(--font-mono);
  font-size:10.5px;letter-spacing:.12em;text-transform:uppercase;color:#5D5D74;
}
.demo-caption{font-size:13.5px;color:var(--muted);text-align:center;margin:16px 0 0}

/* ---------------- shared section bits ---------------- */
.section-head{max-width:760px;margin:0 auto 40px;text-align:center}
.kicker{
  display:block;font-size:12.5px;font-weight:700;letter-spacing:.16em;
  text-transform:uppercase;color:var(--coral);margin-bottom:10px;
}
.section-head h2{font-size:clamp(28px,3.6vw,40px);font-weight:800;letter-spacing:-.03em}
.section-sub{color:var(--muted);margin-top:8px;font-size:16px}

/* ---------------- how it works ---------------- */
.how{max-width:1140px;margin:30px auto 90px;padding:0 26px}
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.step{
  background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);
  padding:30px 26px 28px;position:relative;box-shadow:var(--shadow-sm);
  transition:transform .18s ease, box-shadow .18s ease;
}
.step:hover{transform:translateY(-4px);box-shadow:var(--shadow-md)}
.step-icon{
  display:flex;align-items:center;justify-content:center;width:58px;height:58px;
  background:var(--paper-2);border:2.4px solid var(--ink);
  border-radius:46% 54% 52% 48%/48% 46% 54% 52%;
  box-shadow:3px 3px 0 var(--ink);margin-bottom:18px;transform:rotate(-2deg);
  transition:transform .18s ease;
}
.step:hover .step-icon{transform:rotate(3deg) scale(1.06)}
.step-icon svg{width:34px;height:34px;display:block}
.step:nth-child(2) .step-icon{transform:rotate(2deg)}
.step:nth-child(2):hover .step-icon{transform:rotate(-3deg) scale(1.06)}
.step h3{font-size:20px;margin-bottom:8px;font-weight:800}
.step p{margin:0;color:var(--muted);font-size:15px}

/* ---------------- curriculum ---------------- */
.curriculum{max-width:880px;margin:0 auto 100px;padding:0 26px}
.curriculum-list{display:flex;flex-direction:column;gap:12px}
.cur-item{
  display:flex;align-items:center;gap:18px;text-align:left;width:100%;
  background:var(--paper-2);border:1.5px solid var(--line);border-radius:var(--r-md);
  padding:16px 20px;cursor:pointer;transition:.16s ease;font-family:inherit;
}
.cur-item:hover{border-color:var(--ink);transform:translateX(6px);box-shadow:var(--shadow-hard)}
.cur-item.locked{background:#FBF8F2}
.cur-num{
  width:38px;height:38px;flex:none;display:flex;align-items:center;justify-content:center;
  background:var(--paper);border:1.5px solid var(--line-strong);
  border-radius:46% 54% 52% 48%/48% 46% 54% 52%;
  font-family:var(--font-display);font-weight:800;font-size:16px;color:var(--blue);
  transform:rotate(-2deg);
}
.cur-item:nth-child(even) .cur-num{transform:rotate(2deg)}
.cur-item.locked .cur-num{color:var(--muted)}
.cur-body{flex:1;min-width:0}
.cur-body b{display:block;font-size:16.5px;font-weight:700;letter-spacing:-.01em}
.cur-body span{font-size:13.5px;color:var(--muted);display:block;line-height:1.45}
.cur-tag{
  font-size:12px;color:var(--muted);white-space:nowrap;
  font-family:var(--font-mono);
}
.cur-lock{
  font-size:11.5px;font-weight:700;letter-spacing:.06em;white-space:nowrap;
  padding:5px 12px;border-radius:var(--rd-hand);flex:none;transform:rotate(-1.2deg);
}
.cur-item:not(.locked) .cur-lock{background:rgba(15,191,133,.14);color:#07855C}
.cur-item.locked .cur-lock{background:rgba(255,201,60,.22);color:#8A5B00}

/* ---------------- showcase ---------------- */
.showcase{max-width:1140px;margin:0 auto 100px;padding:0 26px}
.showcase-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.show-card{
  margin:0;background:var(--paper-2);border:1.5px solid var(--line);
  border-radius:18px;overflow:hidden;box-shadow:var(--shadow-sm);
  transition:transform .18s ease, box-shadow .18s ease;
}
.show-card:hover{transform:translateY(-5px);box-shadow:var(--shadow-md)}
.show-card canvas{display:block;width:100%;height:auto;background:var(--dark)}
.show-card figcaption{
  display:flex;align-items:center;gap:9px;
  padding:13px 16px;border-top:1.5px solid var(--line);
}
.cap-icon{width:20px;height:20px;flex:none}
.show-card b{font-family:var(--font-display);font-weight:800;font-size:15.5px;letter-spacing:-.02em;flex:1}
.show-card span{font-family:var(--font-mono);font-size:11px;color:var(--muted);text-align:right}

.fineprint{
  max-width:640px;margin:26px auto 0;text-align:center;
  font-size:12.5px;color:var(--muted);line-height:1.7;
}

/* ---------------- pricing ---------------- */
.pricing{max-width:840px;margin:0 auto 110px;padding:0 26px}
.price-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:22px;align-items:start}
.price-card{
  background:var(--paper-2);border:1.5px solid var(--line-strong);
  border-radius:var(--r-lg);padding:32px 30px;position:relative;
}
.price-card.featured{
  border:2px solid var(--ink);box-shadow:var(--shadow-hard);
}
.price-flag{
  position:absolute;top:-14px;right:24px;background:var(--coral);color:#fff;
  font-size:12px;font-weight:700;letter-spacing:.05em;padding:5px 13px;
  border-radius:999px;box-shadow:0 3px 0 #C43F1D;transform:rotate(2deg);
}
.price-tier{font-size:13.5px;font-weight:700;text-transform:uppercase;letter-spacing:.1em;color:var(--muted)}
.price-amount{
  font-family:var(--font-display);font-size:46px;font-weight:800;
  letter-spacing:-.04em;margin:8px 0 18px;line-height:1;
}
.price-amount span{font-family:var(--font-text);font-size:15px;font-weight:500;color:var(--muted);letter-spacing:0}
.price-amount s{font-family:var(--font-text);font-size:.44em;color:var(--muted);font-weight:600;
  text-decoration-thickness:2px;letter-spacing:0;vertical-align:.38em;margin-right:4px}
.section-sub s{color:var(--muted);text-decoration-thickness:2px}
.section-sub b{color:var(--coral)}
.price-card ul{list-style:none;padding:0;margin:0 0 24px}
.price-card li{
  padding:9px 0 9px 30px;position:relative;font-size:15px;color:var(--ink-2);
  border-bottom:1px dashed var(--line);
}
.price-card li:last-child{border-bottom:none}
.price-card li::before{
  content:'';position:absolute;left:2px;top:13px;width:19px;height:19px;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'%3E%3Cpath d='M3.4 10.6 C5 12.4 6.2 14.4 7.4 16.6 C9.9 10.6 13 5.9 16.8 3.4' fill='none' stroke='%230FBF85' stroke-width='2.6' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") no-repeat center/contain;
}
.price-note{font-size:13px;color:var(--muted);text-align:center;margin:14px 0 0}

/* ---------------- faq ---------------- */
.faq{max-width:780px;margin:0 auto 110px;padding:0 26px}
.faq-list{display:flex;flex-direction:column;gap:12px}
.faq details{
  background:var(--paper-2);border:1.5px solid var(--line);border-radius:var(--r-md);
  padding:0 22px;transition:border-color .15s;
}
.faq details[open]{border-color:var(--ink)}
.faq summary{
  cursor:pointer;list-style:none;padding:19px 0;font-weight:650;font-size:16.5px;
  display:flex;justify-content:space-between;align-items:center;gap:16px;
  font-family:var(--font-display);letter-spacing:-.01em;
}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{
  content:'';width:22px;height:22px;flex:none;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 22 22'%3E%3Cpath d='M11 4.4 V17.6 M4.6 11 H17.4' stroke='%233346E6' stroke-width='2.8' stroke-linecap='round'/%3E%3C/svg%3E") no-repeat center/contain;
  transition:transform .2s;
}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq details p{margin:0 0 20px;color:var(--muted);font-size:15.5px}

/* ---------------- footer ---------------- */
.footer{background:var(--ink);color:#CFC8BE;padding:56px 26px}
.footer-inner{max-width:1100px;margin:0 auto;text-align:center}
.footer-brand{display:flex;align-items:center;justify-content:center;gap:10px;
  font-family:var(--font-display);font-weight:800;font-size:19px;color:#fff;margin-bottom:10px}
.footer p{margin:0 0 20px;font-size:14.5px;color:#9B9289}
.footer-links{display:flex;gap:26px;justify-content:center;margin-bottom:26px;flex-wrap:wrap}
.footer-links a{color:#CFC8BE;text-decoration:none;font-size:14.5px;font-weight:500}
.footer-links a:hover{color:var(--yellow)}
.footer small{color:#6E665E;font-size:12.5px}

/* ---------------- doc pages: contact / refunds / privacy ---------------- */
.doc{max-width:760px;margin:0 auto;padding:56px 26px 96px;min-height:56vh}
.doc h1{font-size:clamp(32px,4.4vw,46px);font-weight:800;letter-spacing:-.03em}
.doc .lede{font-size:18.5px;color:var(--ink-2);max-width:36em;margin:16px 0 0}
.doc .doc-mail{font-family:var(--font-mono);font-size:20px;font-weight:700;margin:22px 0 0;word-break:break-all}
.doc .doc-mail a{color:var(--ink);text-decoration:none}
.doc .doc-mail a:hover{color:var(--blue)}
.doc h2{font-size:21px;font-weight:800;letter-spacing:-.02em;margin:38px 0 8px}
.doc p{margin:12px 0;color:var(--ink-2);line-height:1.75}
.doc ul,.doc ol{margin:14px 0;padding-left:24px;color:var(--ink-2)}
.doc li{margin:9px 0;line-height:1.7}
.doc a{color:var(--blue);font-weight:600;text-decoration:underline;text-decoration-thickness:1.5px;text-underline-offset:3px}
.doc a:hover{color:var(--blue-deep)}
.doc .note{
  background:#FFF8E6;border-left:4px solid var(--yellow);border-radius:0 10px 10px 0;
  padding:13px 17px;font-size:15px;color:#6B4A00;margin:28px 0 0;line-height:1.7;
}
.doc .doc-updated{font-size:13px;color:var(--muted);margin-top:46px}
a.brand{text-decoration:none;color:inherit}
a.brand:hover .brand-name{color:var(--blue)}

/* ============================================================
   WORKSPACE
   ============================================================ */
#workspace{
  display:grid;grid-template-columns:250px minmax(440px,1fr) minmax(360px,470px);
  gap:18px;padding:20px;max-width:1640px;margin:0 auto;align-items:start;
}
#workspace[hidden]{display:none}

/* sidebar */
.lesson-list{display:flex;flex-direction:column;gap:8px;position:sticky;top:84px}
.lesson-item{
  display:flex;gap:11px;align-items:center;text-align:left;width:100%;
  background:var(--paper-2);border:1.5px solid var(--line);border-radius:12px;
  padding:11px 13px;color:var(--ink);cursor:pointer;font-size:13.5px;
  font-weight:600;font-family:inherit;transition:.14s ease;
}
.lesson-item:hover{border-color:var(--line-strong);transform:translateX(3px)}
.lesson-item.active{border-color:var(--ink);box-shadow:var(--shadow-hard);transform:translateX(0)}
.lesson-item.done .lesson-num{background:var(--mint);border-color:var(--mint);color:#04301F}
.lesson-num{
  width:26px;height:26px;flex:none;display:flex;align-items:center;justify-content:center;
  background:var(--paper);border:1.5px solid var(--line-strong);
  border-radius:46% 54% 50% 50%/50% 46% 54% 50%;
  font-family:var(--font-display);font-weight:800;font-size:12.5px;color:var(--blue);
}
.lesson-num .tick{width:13px;height:13px;display:block}
.lock{display:inline-flex;vertical-align:-1px;margin-left:3px}
.lock svg{width:11px;height:11px;display:block;opacity:.75}
.lesson-name{flex:1;line-height:1.3;letter-spacing:-.01em}
.lock{font-size:10.5px;opacity:.85}

/* lesson pane */
.lesson-pane{
  background:var(--paper-2);border:1.5px solid var(--line);border-radius:var(--r-lg);
  padding:26px 28px 24px;box-shadow:var(--shadow-sm);
}
.lesson-meta{display:flex;gap:8px;font-size:11.5px}
.lesson-meta span{
  background:var(--paper);border:1.5px solid var(--line-strong);border-radius:var(--rd-hand);
  padding:4px 13px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);
}
.lesson-meta span:first-child{transform:rotate(-1deg)}
.lesson-meta span:last-child{transform:rotate(1deg)}
.lesson-head h2{font-size:27px;font-weight:800;margin:14px 0 0;letter-spacing:-.03em}
.lesson-goal{
  margin-top:14px;background:#FFF8E6;border-left:4px solid var(--yellow);
  border-radius:0 10px 10px 0;padding:12px 16px;font-size:15.5px;font-weight:600;color:#6B4A00;
}
.lesson-steps{font-size:15px;color:var(--ink-2);margin-top:18px}
.lesson-steps p{margin:12px 0}
.lesson-steps ul,.lesson-steps ol{padding-left:22px;margin:10px 0}
.lesson-steps li{margin:7px 0}
.mini-code{
  display:block;background:var(--dark);color:#D7D7E6;border-radius:10px;
  padding:13px 16px;font-size:13px;overflow-x:auto;margin:12px 0;line-height:1.7;
}

.hint-box{
  background:rgba(51,70,230,.05);border:2px dashed rgba(51,70,230,.55);
  border-radius:var(--rd-hand);padding:2px 18px;margin:20px 0 0;font-size:14.5px;
  transform:rotate(-.3deg);
}
.hint-box summary{
  cursor:pointer;font-weight:700;color:var(--blue);padding:13px 0;
  font-family:var(--font-display);letter-spacing:-.01em;list-style:none;
  display:flex;align-items:center;gap:8px;
}
.hint-box summary::-webkit-details-marker{display:none}
.hint-chevron{transition:transform .2s}
.hint-box[open] .hint-chevron{transform:rotate(90deg)}
.hint-box div{padding:0 0 15px;color:var(--ink-2)}

/* editor */
.editor-wrap{
  margin-top:22px;border:1.5px solid #000;border-radius:16px;overflow:hidden;
  background:var(--dark);box-shadow:0 10px 30px rgba(21,18,16,.18);
}
.editor-bar{
  display:flex;justify-content:space-between;align-items:center;
  background:var(--dark-2);padding:9px 14px;border-bottom:1px solid var(--dark-line);
}
.editor-tab{
  font-family:var(--font-mono);font-size:12.5px;color:#B9B9CC;
  display:flex;align-items:center;gap:8px;background:var(--dark);
  border:1px solid var(--dark-line);border-radius:8px;padding:5px 12px;
}
.editor-tip{font-size:11.5px;color:#61617A;font-family:var(--font-mono)}
#editor{
  display:block;width:100%;height:290px;background:var(--dark);color:var(--dark-text);
  border:none;outline:none;padding:16px 18px;
  font-family:var(--font-mono);font-size:13.5px;line-height:1.75;
  resize:vertical;tab-size:2;caret-color:#5B6BFF;
}
#editor::selection{background:rgba(91,107,255,.35)}
.editor-status{
  display:flex;justify-content:space-between;background:var(--dark-2);
  border-top:1px solid var(--dark-line);padding:6px 14px;
  font-family:var(--font-mono);font-size:11px;color:#5D5D74;
}

/* actions */
.action-row{display:flex;gap:10px;margin:16px 0;flex-wrap:wrap}
.action-row .btn-primary,.action-row .btn-success{font-weight:700}

/* console */
.console{
  background:var(--dark);border:1.5px solid #000;border-radius:14px;overflow:hidden;
}
.console-head{
  display:flex;align-items:center;gap:8px;background:var(--dark-2);
  padding:8px 14px;border-bottom:1px solid var(--dark-line);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;
  text-transform:uppercase;color:#5D5D74;
}
.term-dot{width:8px;height:8px;border-radius:50%;background:var(--mint);
  box-shadow:0 0 0 3px rgba(15,191,133,.16)}
.console-out{
  margin:0;padding:14px 16px;font-family:var(--font-mono);font-size:13px;
  color:#7FE3B2;white-space:pre-wrap;min-height:46px;line-height:1.65;
}
.console-out.console-error{color:#FF8A70}
.console-out.console-error::first-letter{}

/* preview */
.preview-pane{
  background:var(--paper-2);border:1.5px solid var(--line);border-radius:var(--r-lg);
  overflow:hidden;position:sticky;top:84px;box-shadow:var(--shadow-sm);
}
.preview-bar{
  display:flex;justify-content:space-between;align-items:center;gap:10px;
  padding:12px 16px;border-bottom:1px solid var(--line);background:var(--paper);
}
.preview-title{display:flex;align-items:center;gap:8px;font-weight:700;font-size:14px}
.live-dot{width:8px;height:8px;border-radius:50%;background:var(--coral);
  box-shadow:0 0 0 3px rgba(255,91,53,.18);animation:pulse 1.6s infinite}
@keyframes pulse{0%,100%{box-shadow:0 0 0 3px rgba(255,91,53,.18)}50%{box-shadow:0 0 0 6px rgba(255,91,53,.06)}}
.preview-tip{font-size:12px;color:var(--muted);text-align:right}
.preview-frame{background:var(--dark);padding:14px}
#preview{display:block;width:100%;height:340px;border:none;border-radius:12px;background:transparent}
.key-hint{
  display:flex;align-items:center;gap:6px;padding:12px 16px;
  background:var(--paper);border-top:1px solid var(--line);
}
.key-hint kbd{min-width:26px;text-align:center;font-size:13px;padding:3px 7px}
.key-hint span{font-size:12.5px;color:var(--muted);margin-left:6px}

/* ---------------- modal ---------------- */
.modal-backdrop{
  position:fixed;inset:0;background:rgba(21,18,16,.55);backdrop-filter:blur(3px);
  z-index:60;display:flex;align-items:center;justify-content:center;padding:20px;
  animation:fade .16s ease;
}
.modal-backdrop[hidden]{display:none}
@keyframes fade{from{opacity:0}to{opacity:1}}
.modal{
  background:var(--paper-2);border:2px solid var(--ink);border-radius:18px;
  max-width:420px;width:100%;padding:30px 28px 24px;position:relative;overflow:hidden;
  box-shadow:6px 6px 0 var(--ink);animation:pop .18s cubic-bezier(.2,1.4,.4,1);
}
@keyframes pop{from{transform:scale(.94);opacity:0}to{transform:scale(1);opacity:1}}
.modal-bar{position:absolute;top:0;left:0;right:0;height:5px;
  background:linear-gradient(90deg,var(--blue) 0 33%,var(--coral) 33% 66%,var(--yellow) 66%)}
.modal h3{font-size:21px;font-weight:800;margin:6px 0 10px;letter-spacing:-.02em}
.modal p{color:var(--muted);font-size:15px;margin:0 0 22px}
.modal-actions{display:flex;gap:10px;justify-content:flex-end}

/* ---------------- responsive ---------------- */
@media (max-width:1180px){
  .hero{grid-template-columns:1fr;padding-top:52px;gap:40px}
  .hero-demo{max-width:640px;width:100%;margin:0 auto}
  .steps{grid-template-columns:1fr}
  .showcase-grid{grid-template-columns:repeat(2,1fr)}
  #workspace{grid-template-columns:1fr}
  .lesson-list{position:static;flex-direction:row;flex-wrap:wrap}
  .lesson-item{width:auto}
  .preview-pane{position:static}
}
@media (max-width:720px){
  .price-grid{grid-template-columns:1fr}
  .showcase-grid{grid-template-columns:1fr}
  .topbar{flex-wrap:wrap;gap:10px;padding:12px 16px}
  .hero{padding:40px 18px 50px}
  .hero-stats{gap:22px}
  .lesson-pane{padding:20px 18px}
  #editor{height:230px}
  .cur-tag{display:none}
  .window{transform:none}
}