/* Sach (book) reader — built on top of style.css */

/* Reading progress bar */
.reading-progress{position:fixed;top:0;left:0;right:0;height:3px;background:transparent;z-index:100}
.reading-progress-bar{height:100%;width:0;background:linear-gradient(90deg,var(--brand),var(--brand2));
  transition:width .12s ease-out}

/* Top nav for sach */
.sach-nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.95);
  backdrop-filter:blur(12px);border-bottom:1px solid var(--line);box-shadow:var(--shadow-sm)}
.sach-nav .wrap{display:flex;align-items:center;justify-content:space-between;padding:14px 20px;position:relative}
.sach-nav-right{display:flex;gap:18px;align-items:center;font-size:14px}
.sach-nav-right a{color:var(--ink-soft);text-decoration:none;font-weight:500}
.sach-nav-right a:hover{color:var(--brand)}
.chapter-counter{position:absolute;left:50%;transform:translateX(-50%);font-size:12px;font-weight:700;letter-spacing:.8px;color:var(--ink-soft);background:var(--panel2);border:1px solid var(--line);padding:4px 12px;border-radius:999px;white-space:nowrap}

/* Article body */
.sach-article{padding:48px 0 80px;min-height:60vh;background:#fff}
.sach-content{max-width:720px;margin:0 auto;line-height:1.85;font-size:17px;color:var(--ink-soft)}
.sach-content h1{font-size:clamp(28px,4.5vw,40px);margin-bottom:18px;line-height:1.2;color:var(--ink);letter-spacing:-.5px}
.sach-content h2{font-size:clamp(22px,3vw,28px);margin:38px 0 14px;color:var(--brand);letter-spacing:-.2px}
.sach-content h3{font-size:20px;margin:28px 0 10px;color:var(--gold)}
.sach-content h4{font-size:17px;margin:22px 0 8px;color:var(--ink);font-weight:700}
.sach-content p{margin-bottom:14px;color:var(--ink-soft)}
.sach-content ul,.sach-content ol{margin:14px 0 18px 24px;color:var(--ink-soft)}
.sach-content li{margin-bottom:6px}
.sach-content blockquote{border-left:4px solid var(--brand);background:var(--brand-soft);
  padding:16px 20px;margin:18px 0;border-radius:0 10px 10px 0;color:var(--ink);font-style:italic}
.sach-content code{background:var(--panel2);border:1px solid var(--line);padding:2px 7px;border-radius:5px;
  font-size:.92em;font-family:"SF Mono",Monaco,monospace;color:var(--brand)}
.sach-content pre{background:var(--panel2);border:1px solid var(--line);border-radius:12px;padding:16px;
  overflow:auto;margin:14px 0}
.sach-content pre code{border:0;padding:0;background:transparent;color:var(--ink)}
.sach-content table{width:100%;border-collapse:collapse;margin:18px 0;font-size:15px;
  border:1px solid var(--line);border-radius:10px;overflow:hidden;background:#fff}
.sach-content table th,.sach-content table td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line)}
.sach-content table th{background:var(--panel2);color:var(--ink);font-weight:700}
.sach-content table tr:last-child td{border-bottom:0}
.sach-content table tr:hover{background:var(--brand-soft)}
.sach-content img{max-width:100%;border-radius:10px;margin:14px 0}
.sach-content strong,.sach-content b{color:var(--ink);font-weight:700}
.sach-content hr{border:0;border-top:1px solid var(--line);margin:36px 0}
.sach-content a{color:var(--brand);text-decoration:underline;text-underline-offset:3px;font-weight:600}
.sach-content a:hover{color:var(--brand2)}

/* Disable text selection — defense layer */
.sach-content{
  -webkit-user-select:none;
  -moz-user-select:none;
  -ms-user-select:none;
  user-select:none;
  -webkit-touch-callout:none;
}

/* Chapter cover image */
.chapter-cover{max-width:720px;margin:0 auto 36px;border-radius:16px;overflow:hidden;
  box-shadow:0 16px 40px rgba(224,69,123,.15);position:relative;aspect-ratio:21/9;background:var(--panel2)}
.chapter-cover img{width:100%;height:100%;object-fit:cover;display:block}

/* Infographics inside chapter content */
.sach-content img{display:block;margin:28px auto;max-width:100%;border-radius:12px;
  box-shadow:var(--shadow-md);background:#fff;padding:0;border:1px solid var(--line)}
.sach-content figure{margin:24px 0;text-align:center}
.sach-content figcaption{color:var(--muted);font-size:13px;margin-top:8px;font-style:italic}

/* Preview badge */
.preview-badge{display:block;width:fit-content;margin:0 auto 24px;background:var(--ok-soft);color:var(--ok);
  padding:6px 14px;border-radius:999px;font-size:12px;font-weight:800;letter-spacing:.5px;
  text-transform:uppercase}

/* Prev/next pagenav */
.sach-pagenav{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:56px;padding-top:40px;
  border-top:1px solid var(--line);max-width:720px;margin-left:auto;margin-right:auto;align-items:stretch;
  background:transparent!important;position:static!important;backdrop-filter:none!important;border-bottom:none!important;box-shadow:none!important}
.sach-pagenav>div:only-child:has(.sach-next){grid-column:2}
.sach-pagenav a{display:flex;flex-direction:column;justify-content:space-between;padding:18px 20px;background:var(--panel);
  border:1px solid var(--line-strong);border-top:3px solid var(--brand);border-radius:12px;
  color:var(--ink);font-size:14px;font-weight:600;text-decoration:none;
  transition:all .18s ease;line-height:1.5;box-shadow:var(--shadow-sm);min-height:80px;height:100%}
.sach-pagenav a::before{font-size:11px;font-weight:700;letter-spacing:.06em;
  text-transform:uppercase;color:var(--brand);margin-bottom:7px;white-space:nowrap}
.sach-prev::before{content:"← Phần trước"}
.sach-next{text-align:right;align-items:flex-end}
.sach-next::before{content:"Phần tiếp theo →"}
.sach-pagenav a:hover{border-color:var(--brand);background:var(--panel2);
  box-shadow:var(--shadow-md);color:var(--ink)}
@media(max-width:560px){
  .sach-pagenav{grid-template-columns:1fr}
  .sach-pagenav>div:only-child:has(.sach-next){grid-column:1}
  .sach-next{text-align:left;align-items:flex-start}
}

.watermark{display:none;pointer-events:none;
  font-size:20px;font-weight:700;letter-spacing:3px;text-transform:uppercase;
  color:#000;white-space:pre-line;text-align:center;line-height:1.6;
  user-select:none;-webkit-user-select:none}
@media print{.watermark{position:fixed !important;top:50% !important;left:50% !important;right:auto !important;bottom:auto !important;width:auto !important;height:auto !important;display:block !important;transform:translate(-50%,-50%) rotate(-35deg) !important;opacity:.55 !important;font-size:24px !important;letter-spacing:1px !important;text-align:center !important;color:#e0457b !important;-webkit-print-color-adjust:exact !important;print-color-adjust:exact !important}}

/* TOC */
.sach-toc-hero{padding:64px 0 30px;text-align:center;background:
  radial-gradient(800px 400px at 50% 0%,rgba(255,122,168,.18),transparent),var(--bg)}
.sach-toc-hero h1{font-size:clamp(36px,6vw,56px);background:linear-gradient(135deg,var(--brand),var(--gold));
  -webkit-background-clip:text;background-clip:text;color:transparent;letter-spacing:-.5px}
.toc-list{list-style:none;padding:0;max-width:760px;margin:30px auto}
.toc-list li{margin-bottom:10px}
.toc-list a{display:flex;align-items:center;gap:14px;padding:16px 20px;background:#fff;
  border:1px solid var(--line);border-radius:12px;color:var(--ink);text-decoration:none;
  transition:all .15s ease;box-shadow:var(--shadow-sm)}
.toc-list a:hover{border-color:var(--brand);transform:translateX(3px);box-shadow:var(--shadow-md)}
.toc-list .num{color:var(--brand);font-weight:800;font-size:14px;min-width:32px;letter-spacing:.5px}
.toc-list .title{flex:1;font-size:15px;color:var(--ink)}
.preview-pill{display:inline-block;background:var(--ok-soft);color:var(--ok);
  padding:2px 10px;border-radius:999px;font-size:11px;font-weight:800;margin-left:8px}
.lock-pill{margin-left:6px}
.toc-notice{margin-top:36px;padding:20px;background:var(--brand-soft);border-radius:12px;
  text-align:center;max-width:760px;margin-left:auto;margin-right:auto;color:var(--ink-soft)}
.toc-notice a{color:var(--brand);font-weight:800}

/* Footer */
.sach-footer{margin-top:60px;padding:30px 0;border-top:1px solid var(--line);background:var(--panel2);
  text-align:center;color:var(--muted);font-size:13px}
.sach-footer .disclaim{margin-top:8px;font-size:12px;max-width:680px;margin-left:auto;margin-right:auto}

/* ── Vertical section dot nav (desktop only) ── */
.vp-track{position:fixed;top:50%;right:max(32px,calc(50vw - 480px));
  transform:translateY(-50%);z-index:500;display:none;
  flex-direction:column;gap:0;align-items:flex-end}
.vp-track.active{display:flex}
.vp-dot-item{position:relative;display:flex;align-items:center;justify-content:flex-end;
  padding:10px 0;cursor:pointer;gap:12px}
.vp-dot-circle{width:12px;height:12px;border-radius:50%;background:var(--line-strong);
  transition:all .2s;flex:0 0 auto}
.vp-dot-item:hover .vp-dot-circle{background:var(--brand);transform:scale(1.3);
  box-shadow:0 0 8px rgba(224,69,123,.35)}
.vp-dot-item.is-active .vp-dot-circle{background:var(--brand);width:14px;height:14px;
  box-shadow:0 0 10px rgba(224,69,123,.4)}
.vp-dot-label{position:absolute;right:28px;white-space:nowrap;font-size:13px;font-weight:600;
  color:var(--ink);background:var(--panel);border:1px solid var(--line);border-radius:8px;
  padding:6px 12px;box-shadow:var(--shadow-sm);opacity:0;pointer-events:none;
  transform:translateX(6px);transition:all .2s}
.vp-dot-item:hover .vp-dot-label{opacity:1;transform:translateX(0)}
@media(max-width:1100px){.vp-track{right:16px}
  .vp-dot-label{display:none}}
@media(max-width:768px){.vp-track{display:none!important}}

/* ── FAB chapter menu button ── */
.fab-menu{position:fixed;bottom:28px;left:28px;width:52px;height:52px;
  background:#fff;color:var(--ink);border-radius:50%;display:flex;align-items:center;
  justify-content:center;box-shadow:0 8px 24px rgba(0,0,0,.12);border:1px solid var(--line);
  cursor:pointer;z-index:600;backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  transition:transform .15s}
.fab-menu:active{transform:scale(.85);background:var(--brand-soft);color:var(--brand);border-color:var(--brand)}
.fab-menu svg{width:22px;height:22px;stroke:currentColor;stroke-width:1.5;fill:none}
@media(max-width:560px){.fab-menu{bottom:18px;left:18px;width:46px;height:46px}
  .fab-menu svg{width:20px;height:20px}}

/* ── Chapter overlay menu ── */
.ch-overlay{position:fixed;inset:0;background:var(--bg);z-index:2000;
  opacity:0;visibility:hidden;transform:scale(.98);
  transition:all .3s cubic-bezier(.25,1,.5,1);
  overflow-y:auto;-webkit-overflow-scrolling:touch}
.ch-overlay.active{opacity:1;visibility:visible;transform:scale(1)}
.ch-overlay-header{display:flex;align-items:center;justify-content:space-between;
  padding:20px 24px;max-width:760px;margin:0 auto;border-bottom:1px solid var(--line)}
.ch-overlay-header h3{font-size:18px;color:var(--brand);letter-spacing:-.2px;margin:0}
.ch-close{background:none;border:1px solid transparent;border-radius:50%;
  width:40px;height:40px;display:flex;align-items:center;justify-content:center;
  cursor:pointer;color:var(--ink);font-size:20px;transition:border-color .15s}
.ch-close:hover{border-color:var(--line-strong)}
.ch-menu-list{max-width:760px;margin:0 auto;padding:8px 24px 80px}
.ch-menu-item{display:flex;align-items:center;gap:14px;padding:14px 10px;
  border-bottom:1px solid var(--line);cursor:pointer;transition:all .2s;text-decoration:none}
.ch-menu-item:hover{padding-left:15px;border-bottom-color:var(--brand)}
.ch-menu-num{font-size:13px;font-weight:800;color:var(--brand);min-width:32px;letter-spacing:.5px}
.ch-menu-title{font-size:15px;color:var(--ink);flex:1;line-height:1.4}
.ch-menu-item.is-current{background:var(--brand-soft);border-radius:8px;margin:4px -10px;padding:14px 20px}
.ch-menu-item.is-current .ch-menu-title{color:var(--brand);font-weight:700}
.ch-menu-item.is-locked .ch-menu-title{color:var(--muted)}
.ch-menu-lock{font-size:12px;margin-left:auto;flex:0 0 auto}

/* ── Dark mode — sach overrides ── */
@media(prefers-color-scheme:dark){
  .sach-nav{background:rgba(255,255,255,.95)}
  .sach-article{background:var(--bg)}
  .sach-content{color:var(--ink-soft)}
  .sach-content h1{color:var(--ink)}
  .sach-content p{color:var(--ink-soft)}
  .sach-content ul,.sach-content ol{color:var(--ink-soft)}
  .sach-content strong,.sach-content b{color:var(--ink)}
  .sach-content blockquote{background:var(--brand-soft);color:var(--ink);border-left-color:var(--brand)}
  .sach-content code{background:var(--panel2);border-color:var(--line);color:var(--brand)}
  .sach-content pre{background:var(--panel2);border-color:var(--line)}
  .sach-content pre code{color:var(--ink)}
  .sach-content table{background:var(--panel);border-color:var(--line)}
  .sach-content table th{background:var(--panel2);color:var(--ink)}
  .sach-content table td{color:var(--ink-soft);border-color:var(--line)}
  .sach-content table tr:hover{background:var(--brand-soft)}
  .sach-content img{background:var(--panel);border-color:var(--line)}
  .sach-content a{color:var(--brand)}
  .sach-content a:hover{color:var(--brand2)}
  .sach-content hr{border-top-color:var(--line)}
  .chapter-cover{background:var(--panel2);box-shadow:0 16px 40px rgba(0,0,0,.3)}
  .sach-pagenav a{background:var(--panel);border-color:var(--line);color:var(--ink)}
  .sach-pagenav a:hover{border-color:var(--brand);color:var(--brand)}
  .watermark{color:#fff}
  .sach-toc-hero{background:
    radial-gradient(800px 400px at 50% 0%,rgba(240,105,152,.12),transparent),var(--bg)}
  .toc-list a{background:var(--panel);border-color:var(--line);color:var(--ink)}
  .toc-list a:hover{border-color:var(--brand)}
  .toc-list .title{color:var(--ink)}
  .toc-notice{background:var(--brand-soft);color:var(--ink-soft)}
  .sach-footer{background:var(--panel2);border-top-color:var(--line);color:var(--muted)}
  .preview-badge{background:var(--ok-soft);color:var(--ok)}
  .vp-dot-circle{background:var(--line)}
  .vp-dot-item:hover .vp-dot-circle,.vp-dot-item.is-active .vp-dot-circle{background:var(--brand)}
  .vp-dot-label{background:var(--panel);border-color:var(--line);color:var(--ink)}
  .fab-menu{background:var(--panel);border-color:var(--line);color:var(--ink)}
  .fab-menu:active{background:var(--brand-soft);color:var(--brand);border-color:var(--brand)}
  .ch-overlay{background:var(--bg)}
  .ch-overlay-header{border-color:var(--line)}
  .ch-close:hover{border-color:var(--line)}
  .ch-menu-item{border-color:var(--line)}
  .ch-menu-item:hover{border-color:var(--brand);padding-left:15px}
  .ch-menu-num{color:var(--brand)}
  .ch-menu-title{color:var(--ink)}
  .ch-menu-item.is-current{background:var(--brand-soft)}
  .ch-menu-item.is-current .ch-menu-title{color:var(--brand);font-weight:700}
  .ch-menu-item.is-locked .ch-menu-title{color:var(--muted)}
}

/* ── Chapter end CTAs (next chapter + buy) ── */
.chapter-end-cta{max-width:720px;margin:48px auto 0;padding-top:40px;border-top:1px solid var(--line)}
.chapter-next-cta{text-align:center}
.btn-next-chapter{display:inline-flex;align-items:center;gap:8px;padding:14px 28px;
  background:var(--panel);border:1.5px solid var(--brand);border-radius:12px;
  color:var(--brand);font-size:15px;font-weight:700;text-decoration:none;
  transition:all .18s ease;box-shadow:var(--shadow-sm)}
.btn-next-chapter:hover{background:var(--brand);color:#fff;box-shadow:0 8px 22px rgba(224,69,123,.3);transform:translateY(-1px)}

.chapter-buy-cta{background:linear-gradient(135deg,var(--brand-soft),#fff8f3);
  border:1.5px solid var(--brand);border-radius:16px;padding:32px 28px;text-align:center}
.chapter-buy-cta p{color:var(--ink-soft);font-size:16px;line-height:1.65;margin-bottom:10px}
.chapter-buy-cta p:last-of-type{margin-bottom:24px}
.btn-buy-book{display:inline-flex;align-items:center;gap:8px;padding:16px 36px;
  background:linear-gradient(135deg,var(--brand),var(--brand2));color:#fff;
  border-radius:12px;font-size:16px;font-weight:800;text-decoration:none;letter-spacing:.2px;
  box-shadow:0 8px 24px rgba(224,69,123,.35);transition:all .18s ease}
.btn-buy-book:hover{transform:translateY(-2px);box-shadow:0 12px 32px rgba(224,69,123,.45);color:#fff}

/* ── Section dot minimap (right gutter) ── */
#sach-toc-map{position:fixed;right:max(16px,calc((100vw - 800px) / 2 - 50px));
  display:block;z-index:40;will-change:top,height;transition:opacity .2s}
@media(max-width:1099px){#sach-toc-map{display:none}}
.stm-item{position:absolute;right:0;width:11px;display:flex;align-items:center;justify-content:center;
  cursor:pointer;pointer-events:auto;transform:translateY(-50%)}
.stm-dot{width:11px;height:11px;border-radius:50%;background:var(--line-strong);
  flex-shrink:0;transition:background .15s,transform .15s}
.stm-item.stm-h3 .stm-dot{width:7px;height:7px;background:var(--line)}
.stm-item:hover .stm-dot{background:var(--brand);transform:scale(1.3)}
.stm-item.is-active .stm-dot{background:var(--brand);
  animation:stm-pulse 1.8s ease-in-out infinite}
.stm-item.stm-h3.is-active .stm-dot{background:var(--brand2);
  animation:stm-pulse 1.8s ease-in-out infinite}
@keyframes stm-pulse{0%,100%{opacity:1}50%{opacity:.3}}
.stm-label{position:absolute;left:18px;background:var(--ink);color:#fff;
  font-size:12px;font-weight:600;padding:6px 10px;border-radius:4px;
  white-space:normal;width:220px;word-break:normal;overflow-wrap:normal;line-height:1.4;
  opacity:0;pointer-events:none;transform:translateX(-6px);
  transition:opacity .12s,transform .12s;z-index:1}
.stm-label::after{content:"";position:absolute;right:100%;top:50%;
  transform:translateY(-50%);border:5px solid transparent;border-right-color:var(--ink)}
.stm-item:hover .stm-label{opacity:1;transform:translateX(0)}
.stm-item.is-active .stm-label{opacity:1;transform:translateX(0)}