:root{font-family:'Inter',sans-serif;color:#172033;background:#f5f8ff;font-synthesis:none;text-rendering:optimizeLegibility}html{min-width:320px}body{min-height:100vh;background:radial-gradient(ellipse at 8% 0%,rgba(56,189,248,.11),transparent 34%),radial-gradient(ellipse at 95% 15%,rgba(37,99,235,.08),transparent 30%),#f7f9fd;color:#172033}button,input,select,textarea{font:inherit}button{cursor:pointer;transition:transform .18s ease,box-shadow .18s ease,background-color .18s ease}button:hover:not(:disabled){transform:translateY(-1px)}button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:3px solid rgba(6,182,212,.35);outline-offset:2px}header.glass-card{background:rgba(255,255,255,.88);backdrop-filter:blur(16px);border-color:rgba(226,232,240,.85);box-shadow:0 8px 32px rgba(30,64,175,.045)}main{animation:page-in .45s ease both}.tab-content{animation:section-in .3s ease both}.tab-content:not(.hidden){display:block}#tab-chat:not(.hidden){display:flex}#forum-post-input,#pm-desc{resize:vertical}#forum-posts-container>article,#market-books-grid>article{box-shadow:0 8px 24px rgba(30,64,175,.055)}#market-books-grid>article:hover{box-shadow:0 16px 36px rgba(30,64,175,.13)}#gmailNotificationPopup{box-shadow:0 16px 50px rgba(15,23,42,.22)}.tab-content input,.tab-content select,.tab-content textarea,form input,form select,form textarea{transition:border-color .16s ease,box-shadow .16s ease}#market-filter-keyword:focus,#market-filter-cat:focus,#market-filter-price:focus,#market-filter-status:focus{border-color:#3b82f6;box-shadow:0 0 0 3px rgba(59,130,246,.13);outline:none}#chat-messages-box{scrollbar-width:thin;scrollbar-color:#cbd5e1 transparent}#chat-threads-list{scrollbar-width:thin}#profile-avatar-char{display:inline-grid;place-items:center}#adminPortalModal table{min-width:650px}#adminPortalModal .overflow-hidden:has(table){overflow:auto}@keyframes page-in{from{opacity:0}to{opacity:1}}@keyframes section-in{from{opacity:.5;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}@media (max-width:767px),(pointer:coarse) and (max-height:540px){header .max-w-7xl{height:auto;min-height:68px;flex-wrap:wrap;padding-top:10px;padding-bottom:10px}header nav{order:3;width:100%;justify-content:space-between}#tab-chat{height:calc(100dvh - 150px);min-height:440px}#tab-chat>div:first-child{width:38%}#tab-chat>div:last-child{width:62%}#tab-chat form{padding:8px}#tab-chat form button{padding-inline:10px}main{padding-top:16px}}
.register-banner{background:radial-gradient(circle at 92% 15%,rgba(34,211,238,.32),transparent 34%),linear-gradient(135deg,#1e3a8a,#1e40af 62%,#2563eb)}.register-dialog{box-shadow:0 32px 100px rgba(15,23,42,.3)}.register-form label{font-size:12px}.register-form input{min-height:46px}.admin-tabs{scrollbar-width:thin}.admin-tabs button{white-space:nowrap;flex-shrink:0}#notifications-list button:hover{box-shadow:0 8px 24px rgba(30,64,175,.08)}#avatar-file{display:none}#tab-feedback form input:focus,#tab-feedback form textarea:focus,#tab-feedback form select:focus{border-color:#2563eb;outline:3px solid rgba(6,182,212,.18)}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){main{padding-bottom:106px!important}.site-nav{position:fixed;left:0;right:0;bottom:0;z-index:48;order:5;width:100%;height:72px;padding:7px max(10px,env(safe-area-inset-left)) calc(7px + env(safe-area-inset-bottom));background:rgba(255,255,255,.96);border-top:1px solid #e2e8f0;box-shadow:0 -8px 24px rgba(15,23,42,.08);backdrop-filter:blur(16px)}.site-nav button{min-width:0;flex:1;justify-content:center;flex-direction:column;gap:3px;padding:7px 3px!important;border-radius:13px!important}.site-nav button span{display:block!important;font-size:9px;line-height:1.1;white-space:nowrap}.site-nav button i{width:19px;height:19px}.register-dialog{max-height:calc(100dvh - 16px);border-radius:24px}.register-banner{padding:22px!important}.register-form{padding:20px!important}.register-form .grid{grid-template-columns:1fr}.admin-tabs{padding-inline:10px}.admin-tabs button{font-size:11px;padding-inline:11px}.admin-modal-content{height:calc(100dvh - 18px)!important;border-radius:20px}.admin-modal-content>div:last-child{padding:12px!important}#tab-profile>.bg-white:first-child{align-items:flex-start}#tab-profile>.bg-white:first-child>div:first-child{width:100%}#tab-profile>.bg-white:first-child>div:last-child{width:100%}#tab-chat{height:calc(100dvh - 180px);min-height:420px}#tab-chat>div:first-child{width:40%}#tab-chat>div:last-child{width:60%}}
.register-dialog>button{color:#fff;z-index:2}.register-dialog>button:hover{background:rgba(255,255,255,.14);border-radius:10px}.site-nav button{transition:color .16s ease,background-color .16s ease,transform .16s ease}#adminPortalModal{padding:8px}#adminPortalModal table th{position:sticky;top:0;z-index:1;background:#f1f5f9}
/* Community-feed layout */
body{background:#f0f2f5;color:#1c2733}.glass-card{background:rgba(255,255,255,.96)!important}.header-search{background:#f0f2f5;transition:box-shadow .2s,background .2s}.header-search:focus-within{background:#fff;box-shadow:0 0 0 2px rgba(37,99,235,.18)}.forum-layout{max-width:1360px;margin-inline:auto}.forum-left-rail,.forum-right-rail{align-self:start}.forum-left-rail{position:sticky;top:92px}.forum-right-rail{position:sticky;top:92px}.forum-welcome{display:flex;align-items:center;justify-content:space-between;padding:8px 4px 4px}.rail-link{display:flex;align-items:center;gap:12px;width:100%;padding:11px 10px;border-radius:12px;text-align:left;font-size:13px;font-weight:700;color:#3c4b5b}.rail-link:hover{background:#f0f5ff;color:#1e40af}.rail-link svg{width:18px;height:18px;color:#2563eb}.forum-center>div.bg-white{border-radius:18px}.forum-center #forum-post-input{background:#f0f2f5;border:1px solid transparent;border-radius:24px;min-height:50px;font-size:14px}.forum-center #forum-post-input:focus{background:white;border-color:#bfdbfe}.forum-center #forum-posts-container>article{border:0;border-radius:18px;padding:20px;box-shadow:0 1px 2px rgba(20,35,50,.08),0 5px 18px rgba(20,35,50,.035)}.forum-right-rail>div,.forum-right-rail>button{border-radius:18px}.forum-right-rail>div:nth-child(2){background:linear-gradient(145deg,#1e40af,#1d4ed8)!important}.forum-right-rail>div:first-child>div>div{padding:12px;border-radius:12px;background:#f7f9fc}.forum-right-rail>div:first-child>div>div:hover{background:#eff6ff}.forum-center>div:first-child{background:transparent}.forum-center>div:first-child h1{letter-spacing:-.035em}.forum-center #forum-posts-container article footer{padding-top:10px}.forum-center #forum-posts-container article footer button{padding:8px 10px;border-radius:10px}.forum-center #forum-posts-container article footer button:hover{background:#f1f5f9}.forum-right-rail{font-size:13px}#market-books-grid>article{border:1px solid #e7ebf0;border-radius:18px;overflow:hidden}#market-books-grid>article img{transition:transform .35s}#market-books-grid>article:hover img{transform:scale(1.035)}#tab-market>div:first-child{border-radius:22px;background:linear-gradient(120deg,#173a83,#2563eb 75%,#38bdf8)!important}#tab-market h2{letter-spacing:-.03em}#notification-button{background:#f0f2f5}#notification-button:hover{background:#e7edf8}
.post-gallery{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px;overflow:hidden;border-radius:14px;max-height:420px}.post-gallery[data-count="1"]{grid-template-columns:1fr}.post-gallery img{width:100%;height:200px;object-fit:cover;background:#e8edf3}.post-gallery[data-count="1"] img{height:auto;max-height:420px}.book-thumb{width:35px;height:35px;padding:2px;border-radius:9px;background:rgba(255,255,255,.92);border:2px solid white;overflow:hidden;box-shadow:0 2px 8px rgba(15,23,42,.2)}.book-thumb:hover{transform:scale(1.08)}#watermark-preview-box{height:auto;min-height:9rem}.forum-right-rail{position:sticky}.header-search input{min-width:0}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){.post-gallery{gap:4px}.post-gallery img{height:150px}.post-gallery[data-count="1"] img{height:auto;max-height:320px}.forum-right-rail{position:static}.forum-welcome h1{font-size:23px}.book-thumb{height:30px;width:30px}}

.book-detail-panel{animation:section-in .2s ease both}.book-detail-panel button:focus-visible{outline:3px solid rgba(37,99,235,.35);outline-offset:2px}@media (max-width:767px),(pointer:coarse) and (max-height:540px){#book-detail-modal{align-items:flex-end;padding:0}.book-detail-panel{max-height:96dvh;border-radius:24px 24px 0 0}.book-detail-panel img#detail-main-image{height:260px}}

/* Compact phone layout: keep navigation and chat controls inside the viewport. */
*{box-sizing:border-box}img,video{max-width:100%}button,input,select,textarea{max-width:100%}.tab-content{min-width:0}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  header .site-nav{gap:2px!important;padding-inline:5px!important}
  .site-nav button{min-width:0;max-width:20%;padding-inline:1px!important;overflow:visible}
  .site-nav button span{font-size:8px!important;letter-spacing:-.02em}
  #chat-unread-count.hidden{display:none!important}
  #tab-chat{height:calc(100dvh - 166px);min-height:430px;flex-direction:column}
  #tab-chat>div:first-child{width:100%;height:112px;min-height:112px;flex:none;border-right:0;border-bottom:1px solid #e2e8f0}
  #tab-chat>div:first-child>div:first-child{padding:8px 12px}
  #chat-threads-list{display:flex;overflow-x:auto;overflow-y:hidden;flex:none;min-height:58px}
  #chat-threads-list>button{width:132px;min-width:132px;padding:9px!important;border-right:1px solid #e2e8f0}
  #chat-threads-list>div{min-width:100%;padding:12px!important}
  #tab-chat>div:last-child{width:100%;min-height:0;flex:1}
  #tab-chat>div:last-child>div:first-child{padding:10px 12px}
  #chat-messages-box{padding:10px}
  #tab-chat form{padding:8px;gap:6px}
  #chat-template-select{max-width:112px;font-size:10px}
  #chat-input{min-width:0;flex:1 1 90px}
  #tab-chat form button{padding:9px 12px!important}
  #tab-profile .flex.flex-wrap{width:100%}
  #tab-profile .flex.flex-wrap button{flex:1 1 140px;min-height:42px}
  #market-books-grid,#forum-posts-container{min-width:0}
  #tab-feedback form>label,#tab-feedback form>div{min-width:0}
}
.post-gallery img,.post-gallery video{width:100%;height:200px;object-fit:cover;background:#e8edf3}.sp-slot{min-height:120px;overflow:hidden}.sp-slot img{display:block}.sp-label{margin-bottom:8px;color:#2563eb;font-size:9px;font-weight:800;letter-spacing:.14em}@media (max-width:767px),(pointer:coarse) and (max-height:540px){.post-gallery img,.post-gallery video{height:150px}.sp-slot{min-height:90px}}

/* Quảng cáo hai bên lề (màn hình rộng) + footer cố định cuối trang */
.sp-gutter{display:none}
body{display:flex;flex-direction:column}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){#site-footer{padding-bottom:84px}}
.doc-card{display:flex;flex-direction:column;gap:8px}

@keyframes bell-ring{0%,60%,100%{transform:rotate(0)}10%{transform:rotate(14deg)}20%{transform:rotate(-12deg)}30%{transform:rotate(9deg)}40%{transform:rotate(-6deg)}50%{transform:rotate(3deg)}}
#notification-button.has-unread svg,#notification-button.has-unread i{transform-origin:50% 0;animation:bell-ring 2.4s ease-in-out infinite}

/* Làm dịu giao diện cho bớt cảm giác "template" */
.register-banner{background:#1e40af!important}
.register-dialog{box-shadow:0 12px 40px rgba(15,23,42,.18)!important}
.forum-welcome>i,.forum-welcome>svg{display:none!important}
.uppercase[class*="tracking-["]{text-transform:none!important;letter-spacing:0!important}
.font-extrabold{font-weight:700!important}
.rounded-3xl{border-radius:1rem!important}
.rounded-2xl{border-radius:.75rem!important}
.shadow-xl,.shadow-lg{box-shadow:0 1px 3px rgba(15,23,42,.10),0 1px 2px rgba(15,23,42,.06)!important}
.rail-link{border-radius:8px;font-weight:600}

/* ===== v18: quảng cáo — máy tính: hai khoảng trống bên trang chủ; điện thoại: cuối trang chủ ===== */
.sp-media{display:block;width:100%;height:auto;max-height:420px;object-fit:cover;border-radius:12px;margin-bottom:10px;background:#e8edf3}
.sp-slot a{color:inherit;text-decoration:none}
.sp-bottom{display:none}
body.on-home .sp-bottom{display:grid;margin-top:8px}
@media(min-width:1280px){
  body.on-home{--ad-w:clamp(160px,calc((100vw - 1280px)/2 - 28px),260px)}
  body.on-home .sp-gutter{display:block;position:fixed;top:104px;width:var(--ad-w);z-index:30;max-height:calc(100vh - 128px);overflow:auto}
  #sp-gutter-left{left:16px}#sp-gutter-right{right:16px}
  body.on-home > main{max-width:min(80rem,calc(100vw - 2 * var(--ad-w) - 56px))}
  body.on-home .sp-bottom{display:none}
}
/* Nút sáng/tối + tùy chỉnh giao diện nằm sát nút thông báo */
.header-tools{gap:6px}
.header-tools #notification-button{margin-left:0}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){.header-tools{gap:4px}.header-tools #notification-button{width:38px;height:38px;padding:0;display:inline-grid;place-items:center}.header-tools #notification-button.hidden{display:none}}
/* Ô chọn chuyên ngành có nút mũi tên */
.major-combo{position:relative}
.major-combo>input{padding-right:46px!important}
.major-combo-btn{position:absolute;top:50%;right:6px;transform:translateY(-50%);width:34px;height:34px;display:grid;place-items:center;border-radius:10px;color:#475569;background:transparent}
.major-combo-btn:hover,.major-combo.is-open .major-combo-btn{background:rgba(37,99,235,.1);color:#1e40af}
.major-combo-btn svg{transition:transform .2s}
.major-combo.is-open .major-combo-btn svg{transform:rotate(180deg)}
.major-combo-panel{position:absolute;left:0;right:0;top:calc(100% + 6px);z-index:80;max-height:280px;overflow:auto;background:#fff;border:1px solid #e2e8f0;border-radius:12px;box-shadow:0 12px 32px rgba(15,23,42,.16);padding:6px;-webkit-overflow-scrolling:touch}
.major-combo-group{padding:8px 10px 4px;font-size:11px;font-weight:700;color:#64748b;text-transform:none}
.major-combo-item{display:block;width:100%;text-align:left;padding:10px 12px;border-radius:8px;font-size:14px;color:#0f172a}
.major-combo-item:hover,.major-combo-item.is-selected{background:rgba(37,99,235,.1);color:#1e40af;font-weight:600}
.major-combo-empty{padding:12px;font-size:12px;color:#64748b}
html.dark .major-combo-panel{background:rgb(var(--surface));border-color:rgb(var(--line))}
html.dark .major-combo-item{color:rgb(var(--ink))}
html.dark .major-combo-group{color:rgb(var(--muted))}
html.dark .major-combo-btn{color:rgb(var(--ink-2))}
@media(min-width:1280px) and (max-width:1599px){body.on-home .forum-left-rail{grid-column:span 3/span 3}body.on-home .forum-center{grid-column:span 6/span 6}}
@media(max-width:1279px){.sp-media{max-height:260px}}

/* ===== v19: giao diện kiểu app, không thu phóng ===== */
html,body{max-width:100%;overflow-x:hidden;-webkit-text-size-adjust:100%;text-size-adjust:100%}
html{touch-action:pan-x pan-y}
body,button,a,[role="button"],label{touch-action:manipulation;-webkit-tap-highlight-color:transparent}
/* iPhone tự phóng to khi chạm ô nhập có chữ nhỏ hơn 16px */
@media(max-width:1024px) and (pointer:coarse){input:not([type=checkbox]):not([type=radio]):not([type=file]),select,textarea{font-size:16px!important}}
img,video{max-width:100%}

/* ===== v20: quảng cáo — chỉ hiện ô đã cấu hình, không có nhãn ===== */
.sp-slot{min-height:0!important;padding:0!important;overflow:hidden}
.sp-slot>a,.sp-slot>*:not(.sp-media){display:block}
.sp-slot .sp-media{margin:0;border-radius:0;max-height:none}
.sp-slot strong,.sp-slot p,.sp-slot span{margin-left:14px;margin-right:14px}
.sp-slot strong{margin-top:12px}.sp-slot>a>span:last-child,.sp-slot>span:last-child{margin-bottom:12px}
.sp-slot>a>:last-child,.sp-slot>:last-child{margin-bottom:12px}
.sp-slot>a>.sp-media:last-child,.sp-slot>.sp-media:last-child{margin-bottom:0}
.sp-slot.is-empty,.sp-rail,.sp-gutter,.sp-bottom{display:none!important}
.sp-bottom{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px}
/* Điện thoại / máy tính bảng (< 1024px): cuối trang chủ */
@media(max-width:1023px){body.on-home.has-sp .sp-bottom{display:grid!important;margin-top:8px}body.on-home .sp-bottom .sp-slot:not(.is-empty){display:block!important}}
/* Laptop 1024–1279px (thường là màn 1366/1440 có phóng 125–150%): nằm trong hai cột bên trang chủ */
@media(min-width:1024px) and (max-width:1279px){body.on-home .sp-rail:not(.is-empty){display:block!important}}
/* Màn rộng ≥ 1280px: hai khoảng trống hai bên trang chủ */
@media(min-width:1280px){
  body.on-home.has-sp-left .sp-gutter#sp-gutter-left:not(.is-empty),body.on-home.has-sp-right .sp-gutter#sp-gutter-right:not(.is-empty){display:block!important}
  body.on-home:not(.has-sp) > main{max-width:80rem}
}
.sp-rail .sp-media{max-height:200px;object-fit:cover}

/* ===== v23: avatar tròn ===== */
#profile-avatar-box{flex:0 0 80px;width:80px;height:80px;aspect-ratio:1/1;border-radius:9999px}
.chat-avatar{position:relative;flex:0 0 auto;display:inline-grid;place-items:center;border-radius:9999px;overflow:hidden;background:rgb(var(--brand-800,30 64 175));color:#fff;font-weight:700;line-height:1;aspect-ratio:1/1}
.chat-avatar img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.chat-avatar.hidden{display:none}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){#chat-threads-list>button.chat-thread-item{width:168px;min-width:168px;display:flex}}

/* =====================================================================
   v24 — điện thoại 4 mục, bong bóng chat, tìm kiếm + hashtag, trạng thái sách,
   xem ảnh qua lại, chia sẻ, lọc tài liệu, giới thiệu, popup quảng cáo
   ===================================================================== */

/* ---- Badge số đếm: tròn đều, căn giữa, có viền tách nền ---- */
html .count-badge{position:absolute;top:-5px;right:-5px;z-index:2;display:inline-flex!important;align-items:center;justify-content:center;min-width:19px;height:19px;padding:0 5px;border-radius:999px;background:#ef4444;color:#fff;font-size:10.5px;font-weight:800;line-height:1;letter-spacing:0;font-variant-numeric:tabular-nums;box-shadow:0 0 0 2px rgb(var(--surface));pointer-events:none;white-space:nowrap}
html .count-badge.hidden{display:none!important}
#notification-button{position:relative}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){html #notification-count{top:-4px;right:-4px}}

/* ---- Điện thoại: thanh dưới chỉ còn 4 mục ---- */
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  .site-nav .nav-desktop-only{display:none!important}
  .site-nav button{max-width:25%!important;padding:6px 2px!important}
  .site-nav button span{font-size:10.5px!important;letter-spacing:0!important;font-weight:700}
  .site-nav button i,.site-nav button svg{width:21px!important;height:21px!important}
  html .site-nav button.bg-brand-50{background:rgb(var(--brand-500)/.12)!important}
}

/* ---- Bong bóng tin nhắn (chỉ điện thoại, đã đăng nhập) ---- */
.chat-bubble{display:none;position:fixed;left:0;top:0;z-index:57;width:58px;height:58px;border-radius:999px;color:#fff;background:linear-gradient(145deg,rgb(var(--brand-500)),rgb(var(--brand-800)));box-shadow:0 10px 26px -8px rgb(var(--brand-800)/.75),0 2px 6px rgb(15 23 42/.2),inset 0 1px 0 rgb(255 255 255/.25);place-items:center;touch-action:none;user-select:none;-webkit-user-select:none;-webkit-touch-callout:none;--bx:calc(100vw - 72px);--by:calc(100dvh - 160px)}
html .chat-bubble,html .chat-bubble:hover,html .chat-bubble:active{transform:translate3d(var(--bx),var(--by),0)!important;transition:box-shadow .2s ease,opacity .2s ease!important}
.chat-bubble>svg,.chat-bubble>i{width:26px;height:26px;transition:transform .18s ease}
.chat-bubble.is-pressed>svg{transform:scale(.9)}
.chat-bubble.is-dragging{box-shadow:0 18px 40px -10px rgb(var(--brand-800)/.85),0 4px 12px rgb(15 23 42/.25);opacity:.92}
.chat-bubble .count-badge{top:-2px;right:-2px;min-width:22px;height:22px;font-size:11.5px;box-shadow:0 0 0 2.5px rgb(var(--surface))}
.chat-bubble.has-unread::after{content:"";position:absolute;inset:-4px;border-radius:inherit;border:2px solid rgb(var(--brand-400)/.6);animation:bubble-pulse 2s ease-out infinite;pointer-events:none}
@keyframes bubble-pulse{0%{transform:scale(.92);opacity:.9}100%{transform:scale(1.25);opacity:0}}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){.chat-bubble{display:grid}}
html.chat-open .chat-bubble{display:none!important}

/* ---- Điện thoại: tin nhắn mở toàn màn hình như ứng dụng chat ---- */
.chat-close-mobile{display:none}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  html.chat-open,html.chat-open body{overflow:hidden}
  /* main có animation opacity → tạo stacking context, phải tắt để khung chat phủ lên header + thanh dưới */
  html.chat-open main{animation:none!important;opacity:1!important;transform:none!important;filter:none!important}
  html.chat-open #tab-chat:not(.hidden){position:fixed;inset:0;z-index:60;width:100%;height:100dvh!important;min-height:0!important;margin:0;border:0!important;border-radius:0!important;padding-top:env(safe-area-inset-top);padding-bottom:env(safe-area-inset-bottom);animation:chat-sheet-in .28s cubic-bezier(.2,.8,.2,1) both}
  #tab-chat>div:first-child{height:auto!important;min-height:0!important}
  #tab-chat .chat-list-head{padding:8px 8px!important;background:rgb(var(--surface))}
  .chat-close-mobile{display:inline-grid;place-items:center;width:38px;height:38px;border-radius:12px;color:rgb(var(--ink-2));background:rgb(var(--surface-3))}
  .chat-close-mobile+h3{font-size:15px}
  .chat-list-head .chat-close-mobile:last-child{display:none}
  #chat-threads-list{min-height:66px}
}
@keyframes chat-sheet-in{from{transform:translateY(24px);opacity:.4}to{transform:none;opacity:1}}

/* Thông báo nổi luôn trên cùng, không tràn màn hình điện thoại */
#gmailNotificationPopup{z-index:100!important}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){#gmailNotificationPopup{left:12px;right:12px!important;width:auto!important;max-width:none;bottom:calc(86px + env(safe-area-inset-bottom))!important}}

/* ---- Trang chủ: ô tìm kiếm + hashtag ---- */
.home-search{display:flex;flex-direction:column;gap:10px}
.home-search-box{display:flex;align-items:center;gap:10px;padding:0 6px 0 14px;height:48px;border-radius:999px;background:rgb(var(--surface-3));color:rgb(var(--muted));border:1px solid transparent;transition:background-color .2s,border-color .2s,box-shadow .2s}
.home-search-box:focus-within{background:rgb(var(--surface));border-color:rgb(var(--brand-400));box-shadow:0 0 0 4px rgb(var(--brand-500)/.14)}
.home-search-box input{flex:1;min-width:0;height:100%;background:transparent;border:0;outline:none!important;box-shadow:none!important;font-size:14px;color:rgb(var(--ink))}
.home-search-box input::-webkit-search-cancel-button{display:none}
.home-search-box button{display:grid;place-items:center;width:36px;height:36px;border-radius:999px;color:rgb(var(--muted))}
.home-search-box button:hover{background:rgb(var(--line))}
.home-search-box button.hidden{display:none}
.hashtag-bar{display:flex;align-items:center;gap:6px;overflow-x:auto;scrollbar-width:none;padding:1px 2px 2px;-webkit-overflow-scrolling:touch}
.hashtag-bar::-webkit-scrollbar{display:none}
.hashtag-bar-label{flex:none;font-size:11px;font-weight:800;color:rgb(var(--muted));margin-right:2px}
.hashtag-bar-hint{font-size:11.5px;color:rgb(var(--muted));line-height:1.45}
.hashtag-chip{flex:none;display:inline-flex;align-items:center;gap:6px;height:30px;padding:0 10px 0 12px;border-radius:999px;font-size:12.5px;font-weight:700;color:rgb(var(--brand-700));background:rgb(var(--brand-500)/.09);border:1px solid rgb(var(--brand-500)/.14);white-space:nowrap}
.hashtag-chip span{font-size:10.5px;font-weight:800;min-width:18px;height:18px;padding:0 5px;border-radius:999px;display:inline-grid;place-items:center;background:rgb(var(--surface));color:rgb(var(--brand-700))}
.hashtag-chip:hover{background:rgb(var(--brand-500)/.16)}
.hashtag-chip.is-active{background:rgb(var(--brand-700));border-color:rgb(var(--brand-700));color:#fff}
.hashtag-chip.is-active span{background:rgb(255 255 255/.22);color:#fff}
html.dark .hashtag-chip{color:rgb(var(--brand-300))}html.dark .hashtag-chip span{background:rgb(var(--surface-3));color:rgb(var(--brand-300))}
.post-hashtag{display:inline;padding:0;margin:0;font:inherit;font-weight:700;color:rgb(var(--brand-700));background:none;border-radius:4px}
html .post-hashtag:hover:not(:disabled){transform:none;text-decoration:underline}
html.dark .post-hashtag{color:rgb(var(--brand-300))}
.post-search-status{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:8px;padding:10px 14px;border-radius:var(--r-md,12px);background:rgb(var(--brand-500)/.08);color:rgb(var(--ink-2));font-size:13px}
.post-search-status.hidden{display:none}
.post-search-status button{font-size:12px;font-weight:800;color:rgb(var(--brand-700));padding:4px 8px;border-radius:8px}
html.dark .post-search-status button{color:rgb(var(--brand-300))}

/* ---- Chợ sách: màu trạng thái ---- */
.status-badge{display:inline-flex;align-items:center;gap:5px;height:22px;padding:0 9px 0 7px;border-radius:999px;font-size:10.5px;font-weight:800;line-height:1;white-space:nowrap;box-shadow:0 2px 8px -2px rgb(15 23 42/.25)}
.status-badge .status-dot{width:6px;height:6px;border-radius:999px;background:currentColor;opacity:.85}
.status-available{background:#16a34a;color:#fff}
.status-pending{background:#facc15;color:#422006}
.status-sold{background:#dc2626;color:#fff}
.book-card.is-sold .media-slide img,.book-card.is-sold .media-slide video{filter:grayscale(.55) brightness(.92)}
.status-btn{padding:7px 11px;border-radius:9px;font-size:12px;font-weight:700;border:1px solid transparent}
.status-btn-available{background:#dcfce7;color:#166534;border-color:#bbf7d0}
.status-btn-pending{background:#fef9c3;color:#854d0e;border-color:#fde68a}
.status-btn-sold{background:#fee2e2;color:#991b1b;border-color:#fecaca}
html.dark .status-btn-available{background:rgb(22 163 74/.18);color:#86efac;border-color:rgb(22 163 74/.35)}
html.dark .status-btn-pending{background:rgb(250 204 21/.16);color:#fde047;border-color:rgb(250 204 21/.3)}
html.dark .status-btn-sold{background:rgb(220 38 38/.18);color:#fca5a5;border-color:rgb(220 38 38/.35)}

/* ---- Trình xem ảnh: nút qua lại, chấm, số trang ---- */
.media-slider{position:relative;width:100%;height:100%;overflow:hidden;touch-action:pan-y}
.media-track{display:flex;width:100%;height:100%;transition:transform .38s cubic-bezier(.2,.8,.2,1)}
.media-slide{flex:0 0 100%;width:100%;height:100%;overflow:hidden}
.media-slide>img,.media-slide>video{width:100%;height:100%}
.slider-arrow{position:absolute;top:50%;z-index:3;width:36px;height:36px;margin-top:-18px;display:grid;place-items:center;border-radius:999px;color:#0f172a;background:rgb(255 255 255/.9);box-shadow:0 4px 14px rgb(15 23 42/.25);transition:opacity .2s,background-color .2s,transform .2s}
html .slider-arrow:hover:not(:disabled){transform:scale(1.06);background:#fff}
.slider-arrow.prev{left:8px}.slider-arrow.next{right:8px}
.media-slider-card .slider-arrow{width:32px;height:32px;margin-top:-16px;opacity:0}
.book-card:hover .media-slider-card .slider-arrow,.media-slider-card .slider-arrow:focus-visible{opacity:1}
@media(hover:none){.media-slider-card .slider-arrow{opacity:.92}}
.media-slider-detail .slider-arrow{width:42px;height:42px;margin-top:-21px}
.slider-dots{position:absolute;left:50%;bottom:10px;z-index:3;transform:translateX(-50%);display:flex;gap:5px;padding:4px 7px;border-radius:999px;background:rgb(15 23 42/.35)}
.slider-dots span{width:6px;height:6px;border-radius:999px;background:rgb(255 255 255/.55);transition:width .25s,background-color .25s}
.slider-dots span.on{width:16px;background:#fff}
.slider-count{position:absolute;right:10px;bottom:10px;z-index:3;padding:3px 8px;border-radius:999px;font-size:11px;font-weight:700;color:#fff;background:rgb(15 23 42/.55)}
.media-slider-card .slider-count{display:none}
.media-slider-detail .slider-dots{bottom:14px}
.media-slider-detail .slider-count{top:12px;bottom:auto;left:12px;right:auto}

/* ---- Nút chia sẻ + bảng chia sẻ ---- */
.share-icon-btn{flex:none;display:inline-grid;place-items:center;width:30px;height:30px;border-radius:999px;color:rgb(var(--ink-3));background:rgb(var(--surface-3))}
.share-icon-btn:hover{color:rgb(var(--brand-700));background:rgb(var(--brand-500)/.14)}
.share-pill{display:inline-flex;align-items:center;gap:6px;padding:8px 14px;border-radius:999px;font-size:13px;font-weight:700;color:rgb(var(--brand-700));background:rgb(var(--brand-500)/.1);border:1px solid rgb(var(--brand-500)/.18)}
.share-pill:hover{background:rgb(var(--brand-500)/.18)}
.share-pill-sm{padding:6px 10px;font-size:12px;border-radius:8px}
html.dark .share-pill,html.dark .share-icon-btn:hover{color:rgb(var(--brand-300))}
.share-sheet{position:fixed;inset:0;z-index:96;display:flex;align-items:center;justify-content:center;padding:16px}
.share-backdrop{position:absolute;inset:0;background:rgb(2 6 15/.5);backdrop-filter:blur(3px);-webkit-backdrop-filter:blur(3px);opacity:0;transition:opacity .22s}
.share-panel{position:relative;width:min(440px,100%);padding:18px;border-radius:20px;background:rgb(var(--surface));color:rgb(var(--ink-2));box-shadow:0 30px 80px -20px rgb(15 23 42/.45);transform:translateY(16px) scale(.97);opacity:0;transition:transform .28s cubic-bezier(.2,.8,.2,1),opacity .22s}
.share-sheet.is-open .share-backdrop{opacity:1}.share-sheet.is-open .share-panel{transform:none;opacity:1}
.share-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px}
.share-kind{font-size:11px;font-weight:800;color:rgb(var(--brand-600))}
.share-title{margin-top:2px;font-size:16px;font-weight:800;color:rgb(var(--ink));line-height:1.3;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.share-close{flex:none;display:grid;place-items:center;width:36px;height:36px;border-radius:999px;background:rgb(var(--surface-3));color:rgb(var(--ink-3))}
.share-targets{display:grid;grid-template-columns:repeat(auto-fill,minmax(72px,1fr));gap:8px;margin-top:16px}
.share-target{display:flex;flex-direction:column;align-items:center;gap:7px;padding:10px 4px;border-radius:14px;font-size:11.5px;font-weight:700;color:rgb(var(--ink-2));text-align:center;text-decoration:none;line-height:1.2}
.share-target:hover{background:rgb(var(--surface-3))}
.share-icon{display:grid;place-items:center;width:46px;height:46px;border-radius:999px;color:#fff;box-shadow:0 6px 14px -6px rgb(15 23 42/.5)}
.share-icon b{font-size:21px;font-weight:900;font-family:Arial,sans-serif;line-height:1}
.share-label{margin-top:14px;font-size:12px;font-weight:700;color:rgb(var(--muted))}
.share-copy{display:flex;gap:8px;margin-top:8px}
.share-copy input{flex:1;min-width:0;height:44px;padding:0 12px;border-radius:12px;border:1px solid rgb(var(--line));background:rgb(var(--surface-2));font-size:13px;color:rgb(var(--ink))}
.share-copy button{flex:none;display:inline-flex;align-items:center;gap:6px;height:44px;padding:0 14px;border-radius:12px;font-size:13px;font-weight:800;color:#fff;background:rgb(var(--brand-700))}
.share-copy button.is-done{background:#16a34a}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){.share-sheet{align-items:flex-end;padding:0}.share-panel{width:100%;border-radius:22px 22px 0 0;padding:18px 16px calc(18px + env(safe-area-inset-bottom));transform:translateY(100%)}}

/* ---- Tài liệu: bộ lọc ---- */
.filter-chips{display:flex;gap:8px;overflow-x:auto;scrollbar-width:none;padding:2px 1px;-webkit-overflow-scrolling:touch}
.filter-chips::-webkit-scrollbar{display:none}
.filter-chip{flex:none;display:inline-flex;align-items:center;gap:7px;height:38px;padding:0 12px 0 13px;border-radius:999px;font-size:13px;font-weight:700;color:rgb(var(--ink-2));background:rgb(var(--surface));border:1px solid rgb(var(--line));white-space:nowrap}
.filter-chip:hover{border-color:rgb(var(--brand-400)/.6)}
.filter-chip svg{width:16px;height:16px;color:rgb(var(--brand-600))}
.filter-chip-count{min-width:20px;height:20px;padding:0 6px;border-radius:999px;display:inline-grid;place-items:center;font-size:11px;font-weight:800;background:rgb(var(--surface-3));color:rgb(var(--muted))}
.filter-chip.is-active{background:rgb(var(--brand-700));border-color:rgb(var(--brand-700));color:#fff}
.filter-chip.is-active svg{color:#fff}.filter-chip.is-active .filter-chip-count{background:rgb(255 255 255/.22);color:#fff}
.doc-cat{display:inline-flex;align-items:center;height:22px;padding:0 9px;border-radius:999px;font-size:11px;font-weight:800}
.doc-cat-subject{background:#dbeafe;color:#1e40af}.doc-cat-language{background:#ede9fe;color:#5b21b6}.doc-cat-other{background:rgb(var(--surface-3));color:rgb(var(--ink-3))}
html.dark .doc-cat-subject{background:rgb(59 130 246/.18);color:#93c5fd}html.dark .doc-cat-language{background:rgb(139 92 246/.2);color:#c4b5fd}
.doc-subject-chip{display:inline-flex;align-items:center;height:22px;padding:0 9px;border-radius:999px;font-size:11px;font-weight:700;background:#dcfce7;color:#166534}
html .doc-subject-chip:hover:not(:disabled){transform:none;text-decoration:underline}
html.dark .doc-subject-chip{background:rgb(22 163 74/.18);color:#86efac}
.doc-card.is-highlight{box-shadow:0 0 0 3px rgb(var(--brand-500)/.55),var(--shadow-hover)!important;transition:box-shadow .3s}

/* ---- Cuối trang: Giới thiệu + Liên hệ ---- */
.footer-grid{display:grid;grid-template-columns:minmax(0,1.6fr) minmax(0,1fr);gap:28px 48px}
.footer-eyebrow{font-size:11px;font-weight:800;color:rgb(var(--brand-600));letter-spacing:.02em}
.footer-brand{display:flex;align-items:center;gap:12px}
.footer-logo{width:44px;height:44px;object-fit:contain;flex:none}
.footer-about-title{margin-top:2px;font-size:18px;font-weight:800;color:rgb(var(--ink));line-height:1.3}
.footer-about-content{margin-top:12px;font-size:14px;line-height:1.7;color:rgb(var(--ink-3));display:flex;flex-direction:column;gap:10px;max-width:68ch}
.footer-about-content.is-collapsed{max-height:7.2em;overflow:hidden;-webkit-mask-image:linear-gradient(#000 60%,transparent);mask-image:linear-gradient(#000 60%,transparent)}
.footer-more{margin-top:6px;font-size:13px;font-weight:800;color:rgb(var(--brand-700))}
.footer-highlights{margin-top:14px;display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:8px}
.footer-highlights li{display:flex;align-items:flex-start;gap:8px;font-size:13px;font-weight:600;color:rgb(var(--ink-2))}
.footer-highlights svg{flex:none;margin-top:2px;color:#16a34a}
.footer-contact-box{display:flex;flex-direction:column;gap:12px;padding:18px;border-radius:var(--r-lg,16px);background:rgb(var(--surface-2));border:1px solid rgb(var(--line-soft))}
.footer-contact-list{display:flex;flex-direction:column;gap:10px;font-size:14px}
.footer-contact-list>a,.footer-contact-list>span{display:flex;align-items:center;gap:6px;word-break:break-word}
.footer-admin-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:42px;padding:0 16px;border-radius:12px;font-size:13px;font-weight:800;color:#fff;background:rgb(var(--brand-700));align-self:flex-start}
.footer-bottom{border-top:1px solid rgb(var(--line-soft));padding:14px 0;font-size:12px;color:rgb(var(--muted))}
html.dark .footer-eyebrow{color:rgb(var(--brand-400))}html.dark .footer-more{color:rgb(var(--brand-300))}
@media(max-width:768px){.footer-grid{grid-template-columns:1fr;gap:20px}.footer-admin-btn{align-self:stretch}}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){#site-footer{padding-bottom:calc(76px + env(safe-area-inset-bottom))}}

/* ---- Quảng cáo popup ---- */
.sp-popup{position:fixed;inset:0;z-index:95;display:flex;align-items:center;justify-content:center;padding:20px}
.sp-popup-backdrop{position:absolute;inset:0;background:rgb(2 6 15/.62);opacity:0;transition:opacity .22s}
.sp-popup-card{position:relative;max-width:min(440px,100%);transform:scale(.9);opacity:0;transition:transform .32s cubic-bezier(.34,1.56,.64,1),opacity .22s}
.sp-popup.is-open .sp-popup-backdrop{opacity:1}.sp-popup.is-open .sp-popup-card{transform:none;opacity:1}
.sp-popup-card a{display:block;border-radius:18px;overflow:hidden}
.sp-popup-img{display:block;width:auto;max-width:100%;max-height:min(78dvh,680px);border-radius:18px;box-shadow:0 30px 80px -20px rgb(0 0 0/.6);background:#fff;object-fit:contain}
.sp-popup-close{position:absolute;top:-14px;right:-14px;z-index:2;display:grid;place-items:center;width:38px;height:38px;border-radius:999px;color:#0f172a;background:#fff;box-shadow:0 6px 18px rgb(0 0 0/.35)}
html .sp-popup-close:hover:not(:disabled){transform:scale(1.08)}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){.sp-popup-close{top:-12px;right:-6px}}


/* =====================================================================
   v25 — giao diện điện thoại: khung gọn, thẳng hàng, logo nhỏ
   Áp dụng cho điện thoại dọc (≤767px) và điện thoại xoay ngang.
   ===================================================================== */
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  :root{--m-gap:12px;--m-pad:14px}
  main{padding:var(--m-gap) var(--m-gap) calc(96px + env(safe-area-inset-bottom))!important}

  /* Header: một hàng 56px, logo nhỏ */
  header.glass-card>.max-w-7xl{height:56px!important;min-height:56px!important;padding:0 12px!important;flex-wrap:nowrap!important;gap:8px!important}
  header.glass-card>.max-w-7xl>a img{height:30px!important;width:auto!important;max-width:110px}
  .header-tools{gap:6px!important;margin-left:auto!important}
  html .theme-btn,html .header-tools #notification-button{width:36px!important;height:36px!important;padding:0!important;border-radius:10px!important;display:inline-grid;place-items:center}
  html .header-tools #notification-button.hidden{display:none!important}
  .theme-btn svg,#notification-button svg{width:18px!important;height:18px!important}
  #user-controls .text-right{display:none!important}
  #user-controls button{padding:8px!important}
  #guest-controls{gap:6px!important}
  #guest-controls button{padding:8px 11px!important;font-size:12.5px!important;border-radius:10px!important;white-space:nowrap}
  #admin-portal-btn{padding:7px 9px!important;font-size:11px!important}

  /* Khung chung: mọi phần là một thẻ, cùng lề, cùng khoảng cách */
  .tab-content:not(#tab-chat)>*+*,.forum-center>*+*{margin-top:var(--m-gap)!important}
  .forum-layout{gap:var(--m-gap)!important}
  .forum-welcome{display:block!important;padding:var(--m-pad) 16px!important;border-radius:16px!important;background:rgb(var(--surface))!important;border:1px solid rgb(var(--line)/.8);box-shadow:var(--shadow-card)}
  .forum-welcome p:first-child{font-size:11.5px!important}
  .forum-welcome h1,.forum-welcome h2{font-size:20px!important;line-height:1.25!important;margin-top:2px!important}
  .forum-welcome p.text-sm{font-size:13px!important;margin-top:4px!important;line-height:1.45}
  .home-search{padding:10px!important}
  .home-search-box{height:44px}
  .forum-center>.bg-white:not(.home-search){padding:var(--m-pad)!important}
  .forum-center>.bg-white:not(.home-search)>*+*{margin-top:10px!important}
  #forum-avatar-box{width:40px!important;height:40px!important}
  html .forum-center #forum-post-input{min-height:44px!important;height:44px;padding:11px 14px!important;border-radius:22px!important;resize:none}
  html .forum-center #forum-post-input:focus{height:96px;border-radius:16px!important}
  .forum-center>.bg-white:not(.home-search) .pt-3{padding-top:10px!important}
  .forum-center>.bg-white:not(.home-search) .pt-3 button{font-size:13px!important}
  html .forum-center #forum-posts-container>article{padding:var(--m-pad)!important;border-radius:16px!important}
  #forum-posts-container>article>*+*{margin-top:10px!important}
  #forum-posts-container>article header .w-10{width:38px;height:38px}
  #forum-posts-container>article header .font-extrabold{font-size:14px;line-height:1.3;display:flex;flex-wrap:wrap;align-items:center;gap:4px 6px}
  #forum-posts-container>article .post-text{font-size:14.5px;line-height:1.55}
  #forum-posts-container>article footer{gap:6px!important}
  #forum-posts-container>article footer button{flex:1;justify-content:center;padding:9px 6px!important;border-radius:10px;background:rgb(var(--surface-2))}
  #forum-posts-container{gap:var(--m-gap)}
  #forum-posts-container>*+*{margin-top:var(--m-gap)!important}
  .forum-right-rail{display:none!important}

  /* Chợ sách: banner gọn, bộ lọc 2 cột, sách 2 cột như ứng dụng mua sắm */
  html #tab-market>div:first-child{padding:16px!important;gap:12px!important;border-radius:16px!important;align-items:stretch!important;text-align:left}
  #tab-market>div:first-child h2{font-size:20px!important;line-height:1.25;margin-top:8px!important}
  #tab-market>div:first-child span{font-size:10px!important}
  #tab-market>div:first-child>button{padding:11px 14px!important;border-radius:12px!important;font-size:13px!important}
  #tab-market>div:nth-child(2){grid-template-columns:1fr 1fr!important;padding:10px!important;gap:8px!important;border-radius:16px!important}
  #tab-market>div:nth-child(2)>input{grid-column:1/-1}
  #tab-market>div:nth-child(2)>*{min-width:0;height:42px;padding:0 10px!important;font-size:13px!important;border-radius:10px!important}
  #market-books-grid{grid-template-columns:repeat(auto-fill,minmax(158px,1fr))!important;gap:10px!important}
  html #market-books-grid>article{border-radius:14px!important}
  html #market-books-grid>article:hover{transform:none}
  #market-books-grid>article>div[role=button]{height:auto!important;aspect-ratio:4/5}
  #market-books-grid>article>div[role=button]>span:first-of-type{display:none}
  #market-books-grid .status-badge{top:8px!important;right:8px!important;height:20px;font-size:10px;padding:0 7px 0 6px}
  #market-books-grid>article>.p-4{padding:10px!important;gap:8px!important}
  #market-books-grid>article h3{font-size:13px!important;line-height:1.35;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;min-height:2.7em}
  #market-books-grid>article .p-4>button>p,#market-books-grid>article .p-4>button>span{display:none}
  #market-books-grid>article .border-t{padding-top:8px!important;flex-wrap:wrap;gap:4px!important}
  #market-books-grid>article .border-t strong{font-size:14px;width:100%}
  #market-books-grid>article .border-t>span{width:100%;justify-content:space-between}
  #market-books-grid .share-icon-btn{width:28px;height:28px}
  #market-books-grid>article .grid.grid-cols-2{margin-top:8px!important;gap:6px!important}
  #market-books-grid>article .grid.grid-cols-2 button{padding:8px 4px!important;font-size:12px!important;border-radius:10px!important;white-space:nowrap}
  .media-slider-card .slider-arrow{width:28px;height:28px;margin-top:-14px}
  .media-slider-card .slider-arrow.prev{left:5px}.media-slider-card .slider-arrow.next{right:5px}
  .media-slider-card .slider-arrow svg{width:16px;height:16px}
  .media-slider-card .slider-dots{bottom:7px;padding:3px 6px}

  /* Tài liệu */
  #tab-docs>div.bg-white:not(.doc-card){padding:10px!important;gap:8px!important;border-radius:16px!important}
  #tab-docs>div.bg-white:not(.doc-card)>*{width:100%;min-height:42px}
  #docs-list{gap:var(--m-gap)!important}
  #docs-list>.doc-card{padding:var(--m-pad)!important;border-radius:16px!important}
  .doc-card>div:last-child{flex-direction:column;align-items:stretch!important;gap:10px!important}
  .doc-card>div:last-child>div{display:grid!important;grid-template-columns:1fr 1fr;gap:8px!important}
  .doc-card>div:last-child>div>*{justify-content:center;min-height:38px;border-radius:10px!important}
  .doc-card>div:last-child>div>button:not(.share-pill){grid-column:1/-1;order:3;min-height:30px;font-size:12.5px!important}
  .filter-chip{height:36px;font-size:12.5px}

  /* Cá nhân: thông tin xếp gọn, nút 2 cột thẳng hàng */
  #tab-profile>.bg-white{padding:var(--m-pad)!important;border-radius:16px!important}
  #tab-profile>.bg-white:first-child{gap:14px!important}
  #tab-profile>.bg-white:first-child>div:first-child{gap:12px!important;align-items:center!important}
  #profile-avatar-box{flex:0 0 60px!important;width:60px!important;height:60px!important;font-size:22px!important}
  #profile-avatar-box+div{min-width:0}
  #profile-avatar-box+div>div{flex-wrap:wrap;gap:4px 8px!important}
  #profile-name{font-size:17px!important;line-height:1.3}
  #profile-badge{font-size:10.5px!important;padding:2px 8px!important}
  #profile-details{font-size:12px!important;line-height:1.5}
  html #profile-student-actions{display:grid!important;grid-template-columns:1fr 1fr;gap:8px!important;width:100%}
  html #profile-student-actions button{display:flex!important;align-items:center;justify-content:flex-start;gap:8px;min-height:46px!important;padding:8px 12px!important;text-align:left;font-size:12.5px!important;line-height:1.25;border-radius:12px!important;flex:none!important}
  html #profile-student-actions button svg,html #profile-student-actions button i{flex:none;margin:0!important;width:17px;height:17px}
  #push-state{grid-column:1/-1;margin:0}
  #tab-profile form{grid-template-columns:1fr!important}
  #tab-profile input[type=file]{font-size:13px!important;color:rgb(var(--muted))}
  #tab-profile input[type=file]::file-selector-button{margin-right:10px;padding:8px 12px;border:0;border-radius:10px;background:rgb(var(--brand-500)/.12);color:rgb(var(--brand-700));font-weight:700;font-size:12.5px}
  html .forum-center #forum-post-input::placeholder{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

  /* Thông báo, góp ý */
  #notifications-list>button{padding:12px!important}
  #tab-feedback>div:first-child{padding:16px!important}
  #tab-feedback>div:first-child h2{font-size:20px!important}
  #tab-feedback>form,#tab-feedback>div.bg-white{padding:var(--m-pad)!important}

  /* Cuối trang */
  #site-footer{margin-top:16px!important}
  #site-footer .footer-grid{padding:20px 14px!important}
}

/* ===== v26: thanh dưới điện thoại — 4 nút chia đều tuyệt đối, icon + chữ nằm giữa ===== */
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  html header .site-nav{display:grid!important;grid-template-columns:repeat(4,minmax(0,1fr))!important;align-items:stretch;gap:4px!important;height:calc(64px + env(safe-area-inset-bottom))!important;padding:6px 8px calc(6px + env(safe-area-inset-bottom))!important;left:0!important;right:0!important;width:100%!important;margin:0!important}
  html header .site-nav>button:not(.nav-desktop-only){display:flex!important;flex-direction:column!important;align-items:center!important;justify-content:center!important;gap:3px!important;width:100%!important;max-width:none!important;min-width:0!important;height:100%!important;margin:0!important;padding:0!important;border-radius:14px!important;text-align:center;transform:none!important}
  html header .site-nav>button>svg,html header .site-nav>button>i{display:block;flex:none;width:22px!important;height:22px!important;margin:0 auto!important;transform:none!important}
  html header .site-nav>button>span{display:block!important;width:100%;margin:0!important;padding:0!important;font-size:11px!important;line-height:14px!important;text-align:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  html header .site-nav>button.bg-brand-50{background:rgb(var(--brand-500)/.13)!important}
  main{padding-bottom:calc(88px + env(safe-area-inset-bottom))!important}
}


/* ===== v26: thanh 4 nút dưới cùng — chia đều 4 ô, căn giữa, bấm không tràn ===== */
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  html header .site-nav{display:grid!important;grid-template-columns:repeat(4,minmax(0,1fr));align-items:center;justify-items:stretch;gap:4px!important;height:auto!important;min-height:64px;padding:6px 8px calc(6px + env(safe-area-inset-bottom))!important;left:0;right:0;width:100%!important;margin:0!important}
  html header .site-nav>button:not(.nav-desktop-only){display:flex!important;flex-direction:column;align-items:center;justify-content:center;gap:3px!important;width:100%!important;max-width:none!important;min-width:0!important;height:52px;margin:0!important;padding:0 2px!important;border-radius:14px!important;overflow:hidden;position:relative;text-align:center;line-height:1}
  html header .site-nav>button span{display:block!important;width:100%;font-size:11px!important;font-weight:700;line-height:1.1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;text-align:center}
  html header .site-nav>button svg,html header .site-nav>button i{display:block;width:22px!important;height:22px!important;margin:0 auto;flex:none;transform:none!important;transition:transform .15s ease}
  html header .site-nav>button,html header .site-nav>button:hover,html header .site-nav>button:active{transform:none!important;box-shadow:none!important}
  html header .site-nav>button:active svg{transform:scale(.88)!important}
  html header .site-nav>button.bg-brand-50{background:rgb(var(--brand-500)/.13)!important}
}


/* ===== v27: cuộc trò chuyện chưa đọc được làm nổi bật ===== */
.chat-thread-item{position:relative}
.chat-thread-item .thread-time{flex:none;font-size:10px;color:rgb(var(--faint))}
.chat-thread-item.is-unread{background:rgb(var(--brand-500)/.10)}
.chat-thread-item.is-unread::before{content:"";position:absolute;left:0;top:10px;bottom:10px;width:4px;border-radius:0 4px 4px 0;background:rgb(var(--brand-600))}
.chat-thread-item.is-unread .thread-name{font-weight:900;color:rgb(var(--ink))}
.chat-thread-item.is-unread .thread-preview{font-weight:700;color:rgb(var(--ink-2))}
.chat-thread-item.is-unread .thread-time{font-weight:800;color:rgb(var(--brand-600))}
.thread-unread{flex:none;display:inline-flex;align-items:center;justify-content:center;min-width:19px;height:19px;padding:0 6px;border-radius:999px;background:#ef4444;color:#fff;font-size:10.5px;font-weight:800;line-height:1}
.chat-thread-item.is-active{box-shadow:inset 0 0 0 1px rgb(var(--brand-500)/.25)}
html.dark .chat-thread-item.is-unread .thread-time{color:rgb(var(--brand-300))}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  #chat-threads-list>button.chat-thread-item{width:200px!important;min-width:200px!important}
  .chat-thread-item.is-unread::before{top:auto;bottom:0;left:10px;right:10px;width:auto;height:3px;border-radius:3px 3px 0 0}
}

/* =====================================================================
   v28
   ===================================================================== */
/* Logo trang chủ to hơn (ảnh đã cắt sát, nền trong suốt) */
.site-logo{height:50px;width:auto;max-width:none;display:block}
.site-logo-link{flex:none}
@media (max-width:767px),(pointer:coarse) and (max-height:540px){
  html header.glass-card>.max-w-7xl>a img.site-logo{height:38px!important;width:auto!important;max-width:none!important}
}
.footer-logo{width:52px;height:auto}

/* Quảng cáo hai bên (máy tính ≥1280px): banner dọc, đứng yên tại chỗ — cuộn trang thì quảng cáo cuộn theo trang,
   không chạy theo màn hình. Ô nào chưa có quảng cáo thì không hiện. */
@media(min-width:1280px){
  body.on-home .sp-gutter{position:absolute!important;top:104px;width:var(--ad-w);max-height:none!important;overflow:hidden!important;z-index:20;border-radius:16px;background:rgb(var(--surface,255 255 255));border:1px solid rgb(var(--line,226 232 240));box-shadow:0 1px 3px rgba(15,23,42,.08)}
  body.on-home .sp-gutter .sp-media{width:100%;height:auto;max-height:none;aspect-ratio:auto;object-fit:contain;background:transparent}
  body.on-home .sp-gutter:has(.sp-media:only-child),body.on-home .sp-gutter:has(a>.sp-media:only-child){border:0;background:transparent;box-shadow:none}
  body.on-home .sp-gutter:not(:has(.sp-media)){min-height:300px;display:flex;flex-direction:column;justify-content:center}
}

/* Bài viết / tài liệu được mở bằng địa chỉ riêng */
article.is-highlight{box-shadow:0 0 0 3px rgb(var(--brand-500)/.55)!important;transition:box-shadow .3s}
.post-permalink{display:inline-block}
/* Nội dung dựng sẵn từ máy chủ (SEO) — app.js thay bằng giao diện đầy đủ */
#market-books-grid>.ssr-card,#docs-list>.ssr-card{min-width:0}
.ssr-detail{margin-bottom:20px}
.ssr-crumbs a{color:rgb(var(--brand-700))}

/* Chân trang: liên kết khám phá */
.footer-links{display:flex;flex-wrap:wrap;gap:6px 18px;padding-top:0;padding-bottom:18px;font-size:13px;font-weight:700}
.footer-links a{color:rgb(var(--ink-3,71 85 105))}
.footer-links a:hover{color:rgb(var(--brand-700));text-decoration:underline}

/* Liên hệ & mạng xã hội */
.footer-contact-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:8px}
.footer-contact-list.hidden{display:none}
.contact-item{display:flex;align-items:center;gap:10px;min-width:0;padding:8px 10px;border-radius:12px;background:rgb(var(--surface,255 255 255));border:1px solid rgb(var(--line-soft,241 245 249));color:rgb(var(--ink,15 23 42));text-decoration:none;transition:border-color .15s,transform .15s}
.contact-item:hover{border-color:rgb(var(--brand-300));transform:translateY(-1px)}
.contact-email,.contact-phone{grid-column:1/-1}
.footer-contact-list .social-icon{flex:none;width:34px;height:34px;border-radius:10px;display:grid;place-items:center;justify-items:center;text-align:center;color:#fff;line-height:1;font-family:Arial,Helvetica,sans-serif}
.footer-contact-list .social-icon b{display:block;font-weight:900;letter-spacing:-.02em;line-height:1}
.footer-contact-list .contact-text{display:flex;flex-direction:column;align-items:flex-start;gap:1px;min-width:0;text-align:left}
.footer-contact-list .contact-name{display:block;font-size:11px;font-weight:700;color:rgb(var(--muted,100 116 139))}
.footer-contact-list .contact-value{display:block;max-width:100%;font-size:13px;font-weight:700;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
@media (max-width:767px){.footer-contact-list{grid-template-columns:repeat(2,minmax(0,1fr))}}

/* Người bán: số đơn giao dịch thành công */
.seller-stats{display:flex;flex-wrap:wrap;align-items:center;gap:4px 10px;margin-top:4px}
.seller-stat-main{display:inline-flex;align-items:center;gap:5px;font-size:12px;font-weight:700;color:#15803d}
.seller-stat-main b{font-weight:900}
.seller-stat-main.is-zero{color:rgb(var(--muted,100 116 139));font-weight:600}
.seller-stat-sub{font-size:11.5px;color:rgb(var(--muted,100 116 139))}
.seller-stat-sub::before{content:"·";margin-right:6px}
html.dark .seller-stat-main:not(.is-zero){color:#4ade80}

/* Admin: lưu từng mục, xem trước Google */
.adm-sec-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px}
.adm-save-mini{flex:none;padding:7px 14px;border-radius:10px;background:rgb(var(--brand-800));color:#fff;font-size:12px;font-weight:700}
.adm-save-mini:disabled{opacity:.6}
.adm-field{display:flex;flex-direction:column;gap:4px;font-size:12px;font-weight:600;color:#475569}
.adm-count{font-style:normal;font-weight:500;color:#94a3b8;margin-left:6px}
.adm-savebar{position:sticky;bottom:-24px;z-index:5;display:flex;align-items:center;justify-content:flex-end;gap:12px;padding:12px 0;background:linear-gradient(transparent,rgb(var(--surface-2,248 250 252)) 35%)}
.seo-preview{border:1px solid #e2e8f0;border-radius:12px;padding:12px 14px;background:#fff;font-family:Arial,sans-serif}
.seo-preview-url{font-size:12px;color:#202124}
.seo-preview-title{font-size:18px;color:#1a0dab;line-height:1.3;margin-top:2px}
.seo-preview-desc{font-size:13px;color:#4d5156;line-height:1.5;margin-top:2px}

/* Thanh "Đã có phiên bản mới" */
.update-banner{position:fixed;left:50%;bottom:calc(84px + env(safe-area-inset-bottom));transform:translateX(-50%);z-index:90;display:flex;align-items:center;gap:12px;padding:10px 12px 10px 16px;border-radius:14px;background:#0f172a;color:#fff;font-size:13px;font-weight:600;box-shadow:0 12px 32px rgba(15,23,42,.3);max-width:calc(100vw - 24px)}
.update-banner button{padding:7px 12px;border-radius:10px;background:#2563eb;color:#fff;font-weight:800;white-space:nowrap}
@media(min-width:768px){.update-banner{bottom:24px}}

/* Ô tìm kiếm trang chủ: giao diện tối không tô nền riêng cho ô nhập (trước bị lộ một khung tối bên trong) */
html .home-search-box input,html.dark .home-search-box input{background:transparent!important;border:0!important;box-shadow:none!important}

/* Popup: nút "Không hiện lại" */
.sp-popup-card{display:flex;flex-direction:column;align-items:center}
.sp-popup-hide{margin-top:14px;padding:9px 18px;border-radius:999px;background:rgb(255 255 255/.92);color:#0f172a;font-size:14px;font-weight:700;box-shadow:0 6px 18px rgb(0 0 0/.3)}
html .sp-popup-hide:hover:not(:disabled){background:#fff;transform:none}