:root{
  --bg:#ffffff;--bg-alt:#f8f9fa;--bg-card:#ffffff;
  --heading:#1c1e27;--body:#757783;--muted:#9aa1b5;
  --primary:rgb(11, 88, 255);--primary-light:#6B7BEB;--primary-hover:#3D4FC0;--primary-dark:#3A45B0;
  --accent:#4D5FE3;--accent-hover:#3D4FC0;--accent-dark:#3A45B0;--accent-rgb:77,95,227;
  --border:rgba(0,0,0,.08);--border-hover:rgba(0,0,0,.15);
  --glass:rgba(0,0,0,.03);
  --shadow:0 14px 40px rgba(0,0,0,.10);
  --shadow-card:0 2px 12px rgba(0,0,0,.06);
  --shadow-primary:0 0 0 1px rgba(77,95,227,.30),0 16px 46px rgba(77,95,227,.18);
  --heading-font:'Kumbh Sans','Inter',system-ui,sans-serif;
  --body-font:'Roboto','Inter',system-ui,'Segoe UI',sans-serif;
  --side-w:380px;
}
*,*::before,*::after{box-sizing:border-box}
[hidden]{display:none !important}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:var(--body-font);
  color:var(--heading);min-height:100vh;overflow-x:hidden;max-width:100vw;-webkit-font-smoothing:antialiased;
  background:
    radial-gradient(circle at 12% 6%,rgba(77,95,227,.05),transparent 46%),
    radial-gradient(circle at 90% 2%,rgba(77,95,227,.04),transparent 42%),
    linear-gradient(165deg,#ffffff 0%,#fcfcff 45%,#f7f8fd 100%);
}
a{color:inherit;text-decoration:none}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
.hamburger,.sidebar-close,.side-item,.chapter-item{-webkit-tap-highlight-color:transparent}
img{max-width:100%;display:block}
::-webkit-scrollbar{width:8px;height:8px}
::-webkit-scrollbar-thumb{background:rgba(77,95,227,.35);border-radius:10px}
::-webkit-scrollbar-track{background:var(--bg-alt)}

.glow-orb{position:fixed;border-radius:50%;filter:blur(120px);pointer-events:none;z-index:0;opacity:.5}
.orb-rose{width:440px;height:440px;background:rgba(77,95,227,.10);top:-160px;right:-140px}
.orb-plum{width:460px;height:460px;background:rgba(77,95,227,.08);bottom:-200px;left:-160px}

.app-shell{display:flex;min-height:100vh;position:relative;z-index:1}

.sidebar{
  width:var(--side-w);flex-shrink:0;
  background:#ffffff;
  border-right:1px solid var(--border);padding:24px 18px 26px;
  position:sticky;top:0;height:100vh;overflow-y:auto;
  display:flex;flex-direction:column;gap:6px;z-index:50;transition:transform .3s ease;
}
.sidebar-close{display:none}
.side-title{font-family:var(--heading-font);font-size:1.08rem;font-weight:700;color:var(--heading);text-align:center;margin:2px 0 18px;line-height:1.3}
.side-label{font-size:.64rem;font-weight:800;letter-spacing:2.2px;text-transform:uppercase;color:var(--muted);margin:2px 6px 8px}
.side-nav{display:flex;flex-direction:column;gap:8px}
.side-item{display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:13px 14px;border-radius:10px;
  background:var(--bg-card);border:1px solid var(--border);transition:background .2s,border-color .2s,transform .15s}
.side-item:hover{background:var(--bg-alt);border-color:var(--primary-light)}
.si-badge{flex-shrink:0;min-width:42px;text-align:center;font-size:.58rem;font-weight:800;letter-spacing:.5px;
  padding:6px 8px;border-radius:9px;background:rgba(77,95,227,.10);color:var(--primary);border:1px solid rgba(77,95,227,.24)}
.si-text{flex:1;font-size:.86rem;font-weight:600;color:var(--body);line-height:1.3}
.si-count{flex-shrink:0;font-size:.66rem;font-weight:800;padding:4px 10px;border-radius:12px;background:var(--bg-alt);color:var(--body)}
.side-item.active{background:var(--primary);border-color:var(--primary);box-shadow:0 10px 26px rgba(77,95,227,.3);transform:translateX(2px)}
.side-item.active .si-text{color:#fff;font-weight:800}
.side-item.active .si-badge{background:rgba(255,255,255,.2);color:#fff;border-color:rgba(255,255,255,.3)}
.side-item.active .si-count{background:rgba(255,255,255,.2);color:#fff}

.main{flex:1;min-width:0;padding:32px clamp(18px,3.4vw,46px) 60px;position:relative;z-index:1}
.main-head{margin-bottom:22px}
.main-head h1{font-family:var(--heading-font);font-size:clamp(1.5rem,3.2vw,2.1rem);margin:0 0 8px;font-weight:700;line-height:1.15;color:var(--heading);text-wrap:balance}
.main-head p{margin:0;color:var(--body);font-size:.9rem;max-width:640px;line-height:1.6}

.content{max-width:860px;margin:0 auto;width:100%}

.faq{display:flex;flex-direction:column;gap:10px;max-width:860px}
.faq details{background:var(--bg-card);border:1px solid var(--border);border-radius:10px;overflow:hidden;box-shadow:var(--shadow-card)}
.faq summary{list-style:none;cursor:pointer;padding:15px 18px;font-weight:600;font-size:.92rem;display:flex;justify-content:space-between;gap:12px;align-items:center;color:var(--heading);line-height:1.45}
.faq summary::-webkit-details-marker{display:none}
.faq summary:hover{color:var(--primary)}
.faq summary .chev{color:var(--primary);font-weight:800;transition:transform .2s;flex-shrink:0}
.faq details[open] summary .chev{transform:rotate(45deg)}
.faq details[open]{border-color:rgba(77,95,227,.35)}
.faq-body{display:flex;flex-direction:column;gap:10px;padding:0 18px 18px;font-size:.85rem;color:var(--body);line-height:1.7}
.faq-body h3{margin:6px 0 0;font-size:.71rem;font-weight:800;letter-spacing:1.1px;text-transform:uppercase;color:var(--primary);display:flex;align-items:center;gap:10px}
.faq-body h3::after{content:'';flex:1;height:1px;background:var(--border)}
.faq-body h3:first-child{margin-top:12px}
.faq-body p{margin:0}
.faq-body strong{color:var(--heading);font-weight:700}
.faq-body ul,.faq-body ol{margin:0;padding-left:20px;display:flex;flex-direction:column;gap:6px}
.faq-body li{margin:0}
.faq-body a{color:var(--primary);font-weight:600}
.faq-body a:hover{text-decoration:underline}
.faq-body code{background:var(--bg-alt);border:1px solid var(--border);border-radius:6px;padding:1px 6px;font-size:.78em;color:var(--primary-dark)}
.faq-body blockquote{margin:0;padding:10px 14px;border-left:3px solid var(--primary-light);background:var(--bg-alt);border-radius:0 8px 8px 0}

.empty-note{text-align:center;color:var(--muted);padding:34px 0;font-size:.9rem}

.footer{text-align:center;padding:40px 0 10px;display:flex;flex-direction:column;gap:6px;margin-top:30px}
.footer strong{font-size:.82rem;color:var(--body)}
.footer span{font-size:.7rem;color:var(--muted);line-height:1.55}

.mobile-topbar{display:none}
.sidebar-overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.25);z-index:45}

/* logo */
.side-logo-wrap{display:flex;justify-content:center;margin:2px 0 16px;padding:4px}
.side-logo{width:100%;max-width:184px;height:auto;filter:drop-shadow(0 6px 18px rgba(0,0,0,.18))}
.mt-logo{height:34px;width:auto}

@media (max-width:980px){
  .app-shell{position:static}
  .mobile-topbar{display:flex;align-items:center;gap:14px;position:sticky;top:0;z-index:40;padding:12px 16px;
    background:#ffffff;backdrop-filter:blur(12px);border-bottom:1px solid var(--border);box-shadow:var(--shadow-card)}
  .mt-brand{font-family:var(--heading-font);font-size:1.05rem;font-weight:600;color:var(--heading)}
  .hamburger{width:42px;height:42px;border-radius:12px;flex-shrink:0;background:var(--bg-alt);border:1px solid var(--border);
    display:flex;align-items:center;justify-content:center}
  .hamburger span{display:block;width:18px;height:2px;background:var(--heading);position:relative}
  .hamburger span::before,.hamburger span::after{content:'';position:absolute;left:0;width:18px;height:2px;background:var(--heading)}
  .hamburger span::before{top:-6px}
  .hamburger span::after{top:6px}
  .sidebar{position:fixed;left:0;top:0;height:100vh;height:100dvh;transform:translateX(-105%);width:300px;box-shadow:0 0 60px rgba(0,0,0,.4);z-index:50}
  .sidebar.open{transform:translateX(0)}
  .sidebar-overlay.show{display:block}
  body.menu-open{overflow:hidden;height:100dvh}
  .sidebar-close{display:flex;align-items:center;justify-content:center;position:absolute;top:14px;right:14px;width:34px;height:34px;
    border-radius:10px;background:var(--bg-alt);border:1px solid var(--border);color:var(--body);font-size:1.15rem;z-index:2}
  .main{position:relative;z-index:1;padding:20px 16px 50px}
}
@media (max-width:520px){
  .main{padding:16px 12px 40px}
  .faq summary{font-size:.88rem}
}