:root{--ink:#17243a;--sub:#66758c;--blue:#2a63db;--blight:#eaf2ff;--line:#e4eaf2;--soft:#f6f8fb;--green:#188a5c;--glight:#e5f8ee;--red:#c84147;--rlight:#fff0f0;--shadow:0 9px 35px rgba(35,54,88,.055)}
*{box-sizing:border-box}body{margin:0;background:#f5f7fa;font:15px/1.55 system-ui,-apple-system,"Segoe UI",Arial,sans-serif;color:var(--ink)}button,input,select,textarea{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.5}button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:3px solid #93b9ff;outline-offset:2px}a{color:var(--blue)}[hidden]{display:none!important}.layout{display:grid;grid-template-columns:242px minmax(0,1fr);min-height:100vh;max-width:1700px;margin:auto;background:white;box-shadow:0 0 0 1px var(--line)}.sidebar{height:100vh;position:sticky;top:0;overflow:auto;background:#eef1f5;border-right:1px solid #e0e6ed;padding:25px 13px 18px;display:flex;flex-direction:column;z-index:20}.brand{border:0;background:transparent;display:flex;align-items:center;gap:11px;text-align:left;font-size:16px;font-weight:900;color:#12233c;padding:4px 10px 27px;line-height:1.1}.brand small{display:block;margin-top:5px;letter-spacing:.18em;font-size:10px;color:#74849b}.brand-mark{background:#2b65da;color:white;width:39px;height:39px;border-radius:12px;font-size:22px;display:grid;place-items:center}.nav-label{font-size:10px;font-weight:900;letter-spacing:.17em;color:#91a0b1;padding-left:15px;margin:9px 0 8px}.nav{display:flex;flex-direction:column;gap:3px}.nav button,.teacher-nav{border:0;background:transparent;text-align:left;color:#33445b;border-radius:10px;width:100%;padding:10px 13px;font-weight:710;display:flex;align-items:center;gap:11px}.nav button:hover,.teacher-nav:hover{background:#e0e8f2}.nav button.active{background:#dce9ff;color:#2457bc}.nav-item span{font-size:19px;line-height:1;width:20px;text-align:center}.nav .nav-child{padding-left:35px;font-size:13px;font-weight:730;color:#55647b}.nav .nav-leaf{padding:7px 14px 7px 51px;font-weight:620;font-size:12px;color:#6d7c8f}.side-spacer{flex:1}.teacher-nav{border:1px solid #d1dbec;font-size:12px;background:#fff}.demo-flag{font-size:9px;margin-left:auto;color:#8b97aa}.side-disclaimer{font-size:10px;padding:13px 8px 0;color:#9aa5b3;margin:0}.shell{min-width:0}.topbar{height:91px;display:flex;gap:21px;align-items:center;border-bottom:1px solid #edf1f6;padding:19px clamp(20px,3vw,43px);max-width:1500px;margin:auto}.search-form{border:1px solid #d4e1f4;background:#fafcff;border-radius:100px;display:flex;align-items:center;max-width:580px;flex:1;height:45px;min-width:0}.glass{font-size:30px;line-height:1;color:#65758e;padding-left:17px}.search-form input{border:none;background:none;min-width:0;outline:none;flex:1;font-size:13px;padding:0 12px}.search-form button{border:0;border-radius:100px;background:var(--blue);color:white;font-size:12px;font-weight:800;padding:10px 15px;margin-right:5px}.header-right{margin-left:auto;display:flex;gap:5px;white-space:nowrap}.header-right button{font-size:12px;font-weight:800}.text-btn{border:0;background:transparent;padding:10px 12px}.outline-btn{border:1px solid #d5dfed;background:white;border-radius:100px;padding:10px 16px}.content{width:min(1250px,100%);margin:0 auto;padding:32px clamp(18px,4vw,45px) 100px;min-height:calc(100vh - 91px)}.eyebrow{font-size:11px;color:#70819a;font-weight:900;letter-spacing:.15em;text-transform:uppercase}.page-title{font-size:clamp(25px,3.6vw,36px);line-height:1.22;letter-spacing:-.04em;margin:9px 0 12px}.description{color:var(--sub);line-height:1.8;font-size:14px;max-width:740px}.breadcrumb{display:flex;gap:8px;align-items:center;flex-wrap:wrap;font-size:12px;color:#98a4b4;margin-bottom:23px}.breadcrumb button{border:none;background:none;color:#5477ae;padding:0;font-size:12px;font-weight:800}.intro{margin-bottom:25px}.quote{border:2px solid #263348;border-radius:33px;min-height:185px;padding:28px 35px;display:grid;place-items:center;text-align:center;position:relative;background:linear-gradient(120deg,#fff,#f8fbff)}.quote-vi{font-size:clamp(21px,3vw,33px);font-weight:850;letter-spacing:-.04em;line-height:1.35}.quote-zh{font-size:17px;color:#738196;margin-top:10px}.quote-dots{position:absolute;bottom:14px;display:flex;gap:7px}.quote-dots button{height:7px;width:7px;padding:0;border-radius:50%;border:0;background:#cfdae9}.quote-dots button.on{width:21px;border-radius:10px;background:var(--blue)}.streak{margin:24px 0 0;border:1px solid var(--line);box-shadow:var(--shadow);border-radius:23px;padding:22px 25px;display:grid;grid-template-columns:1fr 1.2fr;align-items:center;gap:22px}.streak-label{display:flex;gap:13px;align-items:center}.flame{height:53px;width:53px;border-radius:16px;background:#edf3ff;display:grid;place-items:center;font-size:29px}.streak-label strong{display:block;font-size:18px}.streak-label small{color:var(--sub)}.week{display:grid;grid-template-columns:repeat(7,1fr);gap:7px}.weekday{text-align:center;font-size:11px;font-weight:750;color:#7b889c}.daydot{width:34px;height:34px;border-radius:50%;border:1px solid #e3e9f0;background:#f0f3f8;display:grid;place-items:center;margin:9px auto 0;color:#a2acbb;font-weight:800}.daydot.done{background:var(--green);border-color:var(--green);color:white}.daydot.today{box-shadow:0 0 0 3px #e3edff}.notice{border:1px solid #d7e8ff;border-radius:13px;background:#f4f9ff;padding:12px 15px;color:#526981;font-size:12px;margin-top:14px;line-height:1.7}.section-header{display:flex;justify-content:space-between;align-items:flex-end;gap:12px;margin:35px 0 17px}.section-header h2{margin:0;font-size:20px;letter-spacing:-.025em}.section-header small{color:#91a0b2}.grid{display:grid;gap:15px}.grid.cols-2{grid-template-columns:repeat(2,minmax(0,1fr))}.grid.cols-3{grid-template-columns:repeat(3,minmax(0,1fr))}.tile{border:1px solid var(--line);border-radius:20px;background:#fff;box-shadow:var(--shadow);padding:21px;display:flex;flex-direction:column;align-items:flex-start;min-height:150px;text-align:left;gap:8px;transition:transform .15s,border-color .15s;min-width:0}.tile:hover{transform:translateY(-2px);border-color:#afc7f8}.tile h3{margin:0;font-size:17px;line-height:1.4}.tile p{font-size:12px;color:var(--sub);margin:0;line-height:1.7}.tile-icon{height:43px;width:43px;border-radius:13px;background:#edf3ff;display:grid;place-items:center;color:#2e63b9;font-size:19px;font-weight:850}.tile-arrow{margin-top:auto;align-self:flex-end;color:var(--blue);font-size:13px;font-weight:800}.pill{display:inline-flex;align-items:center;border-radius:50px;padding:4px 10px;background:#edf3ff;color:#3266bc;font-size:10px;font-weight:850}.pill.subtle{background:#f1f5fa;color:#6f8099}.pill.green{background:var(--glight);color:var(--green)}.lesson-card{border:1px solid var(--line);border-radius:16px;background:white;display:flex;align-items:center;text-align:left;padding:17px 20px;gap:13px;min-width:0}.lesson-card:hover{border-color:#9bbbef;background:#fafdff}.lesson-num{width:43px;height:43px;border-radius:12px;display:grid;place-items:center;background:#edf3ff;color:#2f67c1;font-weight:900;flex:none}.lesson-card strong{display:block;font-size:14px}.lesson-card small{display:block;font-size:12px;color:#8190a4;margin-top:4px}.lesson-card>span:last-child{margin-left:auto;color:#8b9aad;font-size:18px}.primary-btn,.secondary-btn,.danger-btn{display:inline-flex;align-items:center;justify-content:center;gap:7px;border-radius:12px;padding:11px 16px;font-weight:800;font-size:13px}.primary-btn{background:var(--blue);color:white;border:1px solid var(--blue)}.primary-btn:hover{background:#2054c3}.secondary-btn{background:white;color:#334c6d;border:1px solid #cdd8e8}.secondary-btn:hover{background:#f6faff}.danger-btn{background:#fff3f3;color:#b83f47;border:1px solid #ffc5c9}.actions{display:flex;gap:9px;flex-wrap:wrap;align-items:center}.mini-note{font-size:12px;color:#75859b;line-height:1.7}.module-tile{min-height:210px}.module-number{font-weight:850;color:#9aafcd;font-size:12px}.module-tile .tile-icon{margin-top:5px}.module-tile h3{font-size:18px}.module-tile p{flex:1}.placeholder{border:1px dashed #bdcadb;border-radius:20px;background:linear-gradient(140deg,#fff,#f9fbff);padding:36px;text-align:center;color:#6b7a91}.placeholder h2{color:var(--ink);margin:5px 0}.placeholder .big{font-size:43px}.placeholder p{max-width:650px;margin:8px auto 20px;font-size:13px;line-height:1.8}.panel{border:1px solid var(--line);background:#fff;border-radius:19px;padding:21px;box-shadow:var(--shadow)}.panel h2,.panel h3{margin:0 0 13px}.panel + .panel{margin-top:16px}.panel-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:17px}.panel-head h2{margin:0}.quiz-top{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:14px;margin-bottom:18px}.big-word{font-size:clamp(42px,7vw,75px);font-weight:750;text-align:center;margin:15px 0 17px;line-height:1.5}.flash-box{border:1px solid #e1e9f4;background:#fafcff;border-radius:24px;padding:19px 24px 25px;max-width:870px;margin:0 auto}.flash-counter{color:#7b8ba4;font-size:12px;font-weight:800}.answers{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin:18px 0 5px}.answer{border:1.4px solid #d8e2ee;border-radius:14px;padding:14px 16px;text-align:left;background:white;color:#35465d;display:flex;gap:11px;align-items:center;font-weight:750;min-width:0}.answer:hover:not(:disabled){border-color:#89b0f5;background:#f6faff}.answer .letter{display:grid;place-items:center;border-radius:8px;background:#eff4fa;width:28px;height:28px;flex:none;color:#7284a0}.answer.correct,.result-question.correct{background:var(--glight);border-color:#7bcba5;color:#176943}.answer.wrong,.result-question.wrong{background:var(--rlight);border-color:#efb0b5;color:#ae323c}.explanation{margin:19px 0 0;border:1px solid #d7e7fa;background:#fff;border-radius:18px;padding:22px}.word-line{display:flex;gap:20px;align-items:center;flex-wrap:wrap}.word-hanzi{font-size:42px;font-weight:770;line-height:1.4}.word-details{display:grid;gap:3px}.word-pinyin{font-size:17px;color:var(--blue);font-weight:700}.word-hanviet{font-size:12px;font-weight:900;color:#66768e}.word-meaning{margin-top:8px;font-size:14px}.word-picture{width:min(100%,300px);height:188px;object-fit:contain;border-radius:13px;border:1px solid var(--line);background:white;margin-top:15px}.radical-list{margin:10px 0;display:flex;flex-wrap:wrap;gap:8px}.radical{padding:10px 12px;border-radius:12px;background:#f4f7fb;font-size:12px;max-width:310px}.radical b{font-size:18px;color:#305da7;margin-right:6px}.radical small{display:block;color:#728197}.module-actions{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;margin:18px 0}.module-actions.end{justify-content:flex-end}.audio-btn{border:1px solid #cdddf3;background:#f4f9ff;color:#285bad;padding:9px 13px;border-radius:10px;font-size:12px;font-weight:800}.audio-player{width:100%;max-width:530px;display:block;margin:12px 0}.quiz-meta{color:var(--sub);font-size:12px}.clock{font-size:18px;font-weight:900;color:#c05529;background:#fff3e7;border:1px solid #f7cda7;border-radius:12px;padding:7px 13px;font-variant-numeric:tabular-nums}.clock.urgent{background:var(--rlight);color:var(--red)}.exam-question{padding:19px 0;border-top:1px solid var(--line)}.exam-question:first-child{border-top:0;padding-top:0}.exam-question h3{font-size:14px;margin:4px 0 12px}.exam-question .answers{margin:10px 0 0}.result-question{padding:17px;margin:11px 0;border:1px solid;border-radius:14px}.result-question h3{font-size:14px;margin:0 0 7px}.result-question p{font-size:12px;margin:6px 0;color:#4a596c}.score-banner{border:1px solid #cfe0f6;border-radius:19px;background:#f0f7ff;padding:19px 23px;display:flex;justify-content:space-between;align-items:center;gap:15px;margin:13px 0 20px}.score-banner strong{font-size:28px;color:#2259ae}.timer-select{display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}.reading{white-space:pre-wrap;font-family:inherit;line-height:2.2;font-size:19px;background:#fafcff;border:1px solid var(--line);padding:25px;border-radius:18px}.teleprompter{background:#101820;color:#f7f7f7;border-radius:19px;overflow:hidden;position:relative;height:350px;margin-top:20px}.teletext{position:absolute;left:9%;right:9%;top:0;padding:0 0 280px;text-align:center;white-space:pre-wrap;line-height:1.8;font-weight:550;transform:translateY(0);will-change:transform}.tele-info{font-size:12px;color:#66768c}.controls{display:flex;align-items:center;gap:13px;flex-wrap:wrap}.controls label{font-size:12px;font-weight:700;color:#62738c}.controls input[type="range"]{vertical-align:middle;accent-color:var(--blue);max-width:160px}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:13px}.field{display:flex;flex-direction:column;gap:5px;margin:0 0 13px}.field label{font-size:12px;font-weight:800;color:#50647d}.field input,.field textarea,.field select{border:1px solid #d3deec;border-radius:10px;padding:10px 12px;background:white;color:#263951;width:100%;min-width:0}.field textarea{min-height:83px;resize:vertical}.field small{color:#8190a3;font-size:11px}.teacher-top{border:1px solid #d6e2f6;background:#f6f9ff;border-radius:18px;padding:21px;margin-bottom:19px}.teacher-tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:17px}.teacher-tabs button{background:#fff;border:1px solid var(--line);padding:9px 13px;border-radius:10px;font-weight:800;font-size:12px}.teacher-tabs button.current{background:#e9f1ff;border-color:#8fb5f3;color:#245cc2}.editor-list{display:flex;flex-direction:column;gap:12px;margin-top:16px}.editor-item{border:1px solid var(--line);background:#fff;border-radius:14px;padding:14px}.editor-item summary{cursor:pointer;font-weight:850;display:flex;align-items:center;gap:10px;list-style:none}.editor-item summary::-webkit-details-marker{display:none}.editor-item summary:after{content:'⌄';margin-left:auto;color:#7e94b4}.editor-item[open] summary{margin-bottom:15px}.upload-note{font-size:11px;color:#66758d}.file-input{font-size:11px!important}.editor-save-bar{display:flex;justify-content:flex-end;gap:10px;margin:20px 0}.toast{position:fixed;bottom:25px;right:25px;background:#18283b;color:white;padding:13px 18px;border-radius:12px;font-size:13px;opacity:0;pointer-events:none;z-index:120;transition:opacity .15s}.toast.on{opacity:1}.modal-overlay{position:fixed;inset:0;z-index:70;background:#14243b85;display:grid;place-items:center;padding:20px}.modal{background:white;border-radius:22px;padding:31px;max-width:460px;width:100%;position:relative}.modal h2{margin:14px 0 8px}.modal p{color:#64758a;font-size:14px;line-height:1.75}.modal-close{position:absolute;top:13px;right:15px;border:0;background:none;font-size:26px}.info-block{background:#eff6ff;border-radius:13px;padding:14px;color:#566b85;font-size:12px;margin-bottom:19px}.overlay{display:none}.split{display:grid;grid-template-columns:1fr 1fr;gap:16px}.activity{display:flex;gap:14px;justify-content:space-between;padding:11px 0;border-bottom:1px solid #edf0f5;font-size:13px}.activity small{color:#9aa8b6}.muted{color:#718196}.empty-text{color:#8997a8;font-size:13px;padding:15px 0}.hr{height:1px;background:#e9eef5;margin:18px 0}.teacher-guard{color:#a3631e;background:#fff8e8;border:1px solid #f1dfae;border-radius:11px;padding:11px 14px;font-size:12px;margin-bottom:15px}
@media(max-width:1000px){.layout{grid-template-columns:210px minmax(0,1fr)}.sidebar{padding:22px 9px}.content{padding:26px 23px 75px}.grid.cols-3{grid-template-columns:repeat(2,minmax(0,1fr))}.topbar{padding:17px 22px}}
@media(max-width:790px){.layout{display:block}.sidebar{position:fixed;left:0;top:0;width:255px;transform:translateX(-102%);transition:transform .18s}.sidebar.open{transform:translateX(0)}.overlay.open{display:block;position:fixed;inset:0;background:#12223870;z-index:15}.menu-toggle{display:block!important}.header-right .text-btn{display:none}.content{padding:24px 20px 65px}.topbar{height:76px;gap:9px}.streak{grid-template-columns:1fr}.grid.cols-3{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(min-width:791px){.menu-toggle{display:none}}
@media(max-width:550px){.topbar{padding:12px 13px}.search-form input{font-size:11px}.search-form button{font-size:0;width:33px;height:33px;flex:none;position:relative;padding:0}.search-form button:before{content:'→';font-size:18px;position:absolute;left:10px;top:3px}.header-right .outline-btn{font-size:11px;padding:8px 11px}.grid.cols-2,.grid.cols-3,.form-grid,.split{grid-template-columns:1fr}.streak{padding:18px 14px}.daydot{width:29px;height:29px}.quote{padding:23px 17px;border-radius:25px;min-height:182px}.tile{min-height:130px}.lesson-card{padding:14px 13px}.answers{grid-template-columns:1fr}.content{padding-left:15px;padding-right:15px}.score-banner{flex-direction:column;align-items:flex-start}.panel{padding:17px}.teleprompter{height:300px}.word-hanzi{font-size:35px}}
.answer.selected{background:#edf3ff;border-color:#699aeb;color:#2455a3}.answer.selected .letter{background:#d4e5ff;color:#2455a3}

/* ====================== LUZD BẢO V4 · BRAND DESIGN SYSTEM ====================== */
:root{
 --ink:#2a2929;--sub:#786b64;--blue:#a93632;--blight:#fff0e5;
 --line:#f0dfd2;--soft:#fff9f3;--green:#218366;--glight:#e5f7ed;
 --red:#bf3d49;--rlight:#fff1f0;--shadow:0 16px 45px rgba(103,56,37,.065);
 --peach:#eb9067;--gold:#efba6e;--cream:#fff8ef;--teal:#377f72
}
html{scroll-behavior:smooth}
body{background:#fff8ef;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,"Noto Sans",sans-serif;font-size:14px;color:var(--ink)}
button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible,a:focus-visible{outline:3px solid #efb068;outline-offset:3px}
.layout{max-width:none;grid-template-columns:255px minmax(0,1fr);background:#fffcf8;box-shadow:none}
.sidebar{background:linear-gradient(180deg,#fff8ef 0%,#ffefe5 100%);border-right:1px solid #eedbcc;padding:32px 16px 18px}
.brand{font-size:15px;padding:1px 3px 32px 5px;gap:12px;letter-spacing:-.03em;white-space:nowrap}
.brand-copy em{font-style:normal;color:#ad3a31}
.brand-mark{height:48px;width:48px;border-radius:16px;background:linear-gradient(145deg,#ad3930,#7d2327);color:#fff5e9;font-family:serif;font-size:29px;box-shadow:0 7px 18px #9c37344c;transform:rotate(-6deg)}
.brand small{color:#b18773;font-size:9px;margin-top:7px;letter-spacing:.08em;font-weight:850}
.nav-label{color:#bb8c74;font-size:10px;padding-left:14px;margin-bottom:13px;letter-spacing:.16em}
.nav{gap:4px}
.nav button,.teacher-nav{color:#645049;border-radius:13px;padding:11px 12px;font-weight:750;transition:background .17s,color .17s}
.nav button:hover,.teacher-nav:hover{background:#ffe3d4;color:#8f352d}
.nav button.active{color:#a1332f;background:#ffe1d4;box-shadow:inset 3px 0 0 #b43e32}
.nav-item span{color:#b45147;font-size:21px}
.nav .nav-child{color:#926e5a;padding-left:37px;font-weight:750}
.nav .nav-leaf{color:#94776b}
.sidebar-note{display:flex;align-items:center;gap:12px;color:#7d5849;background:#ffe8d8;border:1px solid #f6d4be;border-radius:17px;padding:15px 12px;font-size:11px;line-height:1.6;margin:16px 0 12px}
.sidebar-note .sparkle{font-size:26px;color:#b24b35}
.sidebar-note strong{color:#9a3733}
.teacher-nav{background:#fffaf5;border-color:#ead5c2;color:#a23934;font-weight:760}
.demo-flag{font-size:9px;color:#b48073}
.side-disclaimer{font-size:10px;padding:13px 8px;color:#a68672}
.shell{display:flex;flex-direction:column;min-height:100vh;min-width:0}
.topbar{height:86px;max-width:none;width:100%;gap:26px;border-bottom:1px solid #f1e5db;padding:17px clamp(24px,3.8vw,58px);background:#fffdfa}
.search-form{height:46px;background:#fffaf6;border:1px solid #efdaca;max-width:620px;box-shadow:0 4px 15px #7e442f06}
.search-form:focus-within{border-color:#c77350;box-shadow:0 0 0 3px #efba9655}
.glass{color:#a96952}
.search-form input{font-size:13px;color:#433c36}
.search-form input::placeholder{color:#ae9c8e}
.search-form button{font-size:12px;background:#a93632;border-radius:24px;margin-right:5px;padding:11px 18px}
.search-form button:hover{background:#8f2d2a}
.header-right .text-btn{color:#7c5750}
.outline-btn{border-color:#ead0bd;color:#a23830;border-radius:25px;background:#fff9f3;padding:10px 19px;box-shadow:0 4px 12px #a9572d12}
.outline-btn:hover{background:#ffede1}
.mobile-wordmark{display:none;font-size:12px;color:#96332f;font-weight:850;letter-spacing:.04em;white-space:nowrap}
.mobile-wordmark strong{font-weight:950}
.content{width:min(1370px,100%);padding:30px clamp(24px,3.7vw,58px) 65px;flex:1}
.site-footer{border-top:1px solid #f2e3d8;padding:19px clamp(24px,3.7vw,58px);display:flex;align-items:center;justify-content:space-between;gap:15px;color:#9c8070;font-size:11px}
.site-footer button{border:0;background:none;color:#a53d32;font-weight:760;font-size:11px}
.eyebrow{color:#b35f45;font-size:11px;letter-spacing:.13em}
.page-title{font-size:clamp(30px,4vw,46px);font-weight:860;letter-spacing:-.045em;color:#362b29;margin:8px 0 12px}
.description{color:#7c6b62;line-height:1.8;max-width:770px}
.intro{margin-bottom:29px}
.breadcrumb{color:#b9a398}
.breadcrumb button{color:#a94435}
.section-header{margin:40px 0 17px;align-items:flex-end}
.section-header h2{font-size:clamp(21px,2.2vw,26px);letter-spacing:-.035em}
.section-header .eyebrow{margin-bottom:6px}
.section-header .description{margin:4px 0 0}
.grid{gap:18px}
.tile,.panel,.lesson-card{border-color:#efdfd3;box-shadow:var(--shadow)}
.tile{border-radius:22px;padding:22px;gap:10px;background:#fffefd;transition:transform .2s,border-color .2s,box-shadow .2s}
.tile:hover{transform:translateY(-4px);border-color:#e8af94;box-shadow:0 18px 40px #9f5f4124}
.tile:active{transform:translateY(-1px)}
.tile h3{color:#3e302e;font-size:18px;letter-spacing:-.02em}
.tile p{color:#89746a;font-size:13px}
.tile-icon{width:48px;height:48px;background:#fff0e6;border-radius:15px;color:#a83e33;font-size:22px}
.tile-arrow{color:#aa3e34;margin-top:auto}
.pill{background:#fdf0e8;color:#a0473e;font-size:10px;letter-spacing:.035em}
.pill.peach{background:#fff0e3;color:#aa654c}
.pill.subtle{background:#f9f2ec;color:#947b6e}
.pill.green{background:#e8f6ed;color:#288363}
.lesson-card{border-radius:15px;padding:17px 20px}
.lesson-card:hover{border-color:#dfa486;background:#fff8f2}
.lesson-num{background:#fff0e6;color:#aa4939;border-radius:13px}
.lesson-card small{color:#938177}
.primary-btn{background:#a93632;border-color:#a93632;border-radius:12px}
.primary-btn:hover{background:#8f2926}
.secondary-btn{border-color:#e9d4c4;color:#8b5144;background:#fffcf8}
.secondary-btn:hover{background:#fff1e4}
.danger-btn{color:#b14446;background:#fff3f0}
.notice{background:#fff6ed;border-color:#efdcc7;color:#8b6857;border-radius:14px;font-size:12px}
.panel{border-radius:21px;padding:23px;background:#fffefd}
.panel h2{font-size:19px;color:#46312e}
.panel-head{flex-wrap:wrap}
.mini-note{color:#968074}
.split{gap:18px}
.activity{border-color:#f3e6dd}
.activity small{color:#ac9688}
.empty-text{color:#9d877c}
.placeholder{background:linear-gradient(140deg,#fffefd,#fff6ec);border-color:#e3c5b3;color:#9a7767;border-radius:23px}
.placeholder h2{color:#463630}
.module-number{color:#c18967}
.module-tile{background:linear-gradient(160deg,#fff,#fffaf5)}
.module-tile:nth-child(2){background:linear-gradient(160deg,#fff,#fff3e8)}
.module-tile:nth-child(3){background:linear-gradient(160deg,#fff,#eff9f5)}
.module-tile:nth-child(3) .tile-icon{background:#e5f6ef;color:#377f72}
.flash-box{background:#fffaf6;border-color:#eedaca;border-radius:26px}
.big-word{color:#a43630;font-family:ui-serif,"Noto Serif CJK SC",STSong,serif}
.answer{border-color:#eddcd2;color:#5c4b43;border-radius:15px}
.answer:hover:not(:disabled){border-color:#d99b77;background:#fff5ed}
.answer .letter{background:#fff0e5;color:#aa6a50}
.answer.correct,.result-question.correct{background:#e8f8ed;border-color:#7cceb0;color:#1a7551;opacity:1}
.answer.wrong,.result-question.wrong{background:#fff0ee;border-color:#eaa6a3;color:#b34443;opacity:1}
.answer.selected{background:#fff0e5;border-color:#c87e58;color:#983a31}
.answer.selected .letter{background:#ffd9c1;color:#8f382e}
.explanation{background:#fffcf8;border-color:#f0dfd1}
.word-pinyin{color:#a94433}
.radical{background:#fff2e8}
.radical b{color:#9d4136}
.word-line .word-hanzi{color:#a6362f}
.audio-btn{background:#fff2e7;border-color:#e5b89e;color:#994334}
.score-banner{background:#fff2e8;border-color:#edd2bd}
.score-banner strong{color:#a83a33}
.clock{background:#fff3df;color:#aa4b2c}
.reading{background:#fffbf6;border-color:#f0dfd2}
.teleprompter{background:#211a1b;border:5px solid #3c2b29;box-shadow:0 14px 32px #2f1b1d24}
.controls label{color:#75594d}
.form-grid .field label,.field label{color:#795f51}
.field input,.field textarea,.field select{border-color:#ead8c8;color:#40312d;background:#fffefa}
.teacher-top{border-color:#f0d8c3;background:#fff7ee}
.teacher-tabs button{border-color:#ebdace}
.teacher-tabs button.current{background:#ffeadd;border-color:#eab58c;color:#a34230}
.editor-item{border-color:#ecdccc}
.editor-item[open]{background:#fffdf9}
.teacher-guard{background:#fff2df;color:#9a6033;border-color:#edcda3}
.info-block{background:#fff4e9;color:#886a59}
.modal{border-radius:25px;box-shadow:0 25px 85px #23171035}
.modal-actions{display:grid;gap:10px}
.modal-actions button{width:100%}
.toast{background:#3c2926;color:white;box-shadow:0 12px 30px #321c1b30}

/* HOME — HERO */
.hero{position:relative;overflow:hidden;min-height:388px;border-radius:30px;background:radial-gradient(circle at 82% 22%,#ffe8c7 0,#fff2df 32%,#fff4e6 55%,#fff0e3 95%);border:1px solid #f1dccc;padding:49px 45px;display:grid;grid-template-columns:minmax(0,1.2fr) minmax(260px,.8fr);gap:16px;isolation:isolate;box-shadow:0 21px 55px #bc76551a}
.hero:before{content:"";position:absolute;height:380px;width:380px;border-radius:50%;background:#ffdec6a1;right:-160px;top:-140px;z-index:-1}
.hero:after{content:"";position:absolute;bottom:-160px;left:40%;height:290px;width:290px;border:2px solid #edbd9a55;border-radius:50%;z-index:-1}
.hero-content{position:relative;z-index:2;align-self:center}
.hero-kicker{display:inline-flex;align-items:center;gap:8px;font-size:10px;font-weight:900;letter-spacing:.14em;color:#a9583d}
.hero-dot{height:7px;width:7px;background:#a83c31;border-radius:50%;box-shadow:0 0 0 4px #eec9b4}
.hero h1{font-size:clamp(31px,3.5vw,52px);letter-spacing:-.055em;line-height:1.19;margin:18px 0;color:#56362f;font-weight:900;max-width:680px}
.hero h1 span{color:#ac372f}
.hero-content>p{font-size:14px;line-height:1.85;color:#775d50;max-width:505px;margin:0}
.hero-actions{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin:25px 0 18px}
.hero-primary{padding:13px 20px;border-radius:13px;box-shadow:0 8px 22px #a2342940}
.hero-primary span{margin-left:8px}
.hero-link{border:0;background:transparent;color:#90453c;font-weight:800;padding:11px}
.hero-link:hover{color:#5b2c28}
.hero-proof{font-size:11px;color:#a17c67;display:flex;gap:8px;align-items:center}
.hero-proof-icon{color:#b84d3d}
.hero-visual{position:relative;min-height:280px;align-self:stretch}
.hero-ink{position:absolute;font-family:ui-serif,"Noto Serif CJK SC",STSong,serif;font-size:clamp(180px,19vw,290px);color:#a53d30;opacity:.94;right:13%;top:50%;transform:translateY(-51%) rotate(-8deg);line-height:1;text-shadow:9px 9px 0 #efbd9a55;filter:drop-shadow(4px 13px 8px #ac604e28)}
.hero-ink span{position:absolute;font:25px system-ui;color:#ffb875;left:5%;bottom:3%;transform:rotate(8deg)}
.hanzi-orbit{position:absolute;display:grid;place-items:center;border:1px solid #e1b19c;background:#fffbf2b8;box-shadow:0 7px 16px #ad634927;color:#a94b37;border-radius:50%;font-family:serif;font-size:25px;z-index:2}
.orbit-one{width:58px;height:58px;left:6%;top:13%;transform:rotate(-14deg)}
.orbit-two{width:42px;height:42px;right:3%;top:14%;font-size:21px}
.orbit-three{width:45px;height:45px;left:12%;bottom:17%;font-size:22px}
.hero-seal{position:absolute;right:3%;bottom:10%;display:grid;place-items:center;border-radius:7px;background:#a73e33;color:#fff1d8;font-size:11px;font-weight:900;line-height:1.2;text-align:center;padding:14px;transform:rotate(10deg);border:2px solid #a73e33;outline:1px solid #fff6e3;outline-offset:-6px}
.visual-note{position:absolute;right:2%;bottom:0;transform:translateY(5px);font-family:ui-serif,STSong,serif;color:#a36250;font-size:15px;z-index:2;white-space:nowrap}
.visual-note span{display:block;font-family:Arial,sans-serif;font-size:10px;letter-spacing:.03em;color:#bb907a}
.feature-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin:20px 0 0}
.widget-eyebrow{font-size:10px;letter-spacing:.12em;color:#b26e54;font-weight:900}
.quote{min-height:220px;border:1px solid #f0d6c5;border-radius:23px;text-align:left;padding:27px 29px;display:flex;flex-direction:column;justify-content:center;align-items:flex-start;background:linear-gradient(130deg,#fffdfa,#fff3e6);box-shadow:var(--shadow)}
.quote-vi{font-size:clamp(18px,1.85vw,25px);color:#743e33;letter-spacing:-.03em;font-weight:850;line-height:1.4;margin-top:15px;padding-right:30px}
.quote-zh{font-size:16px;color:#ae765f;margin-top:12px;font-family:ui-serif,STSong,serif}
.quote-dots{position:relative;bottom:auto;display:flex;margin-top:18px;gap:6px}
.quote-dots button{background:#e8c4b0}
.quote-dots button.on{background:#aa3d30}
.streak{margin:0;border:1px solid #eddfcc;border-radius:23px;background:linear-gradient(130deg,#fffefa,#f8fff9);min-height:220px;padding:23px 28px;box-shadow:var(--shadow);display:flex;flex-direction:column;align-items:stretch;justify-content:center;gap:18px}
.flame{background:linear-gradient(145deg,#ffddc5,#ffefdf);box-shadow:0 5px 15px #be68451a;border-radius:15px}
.streak-label strong{font-size:23px;color:#674536;line-height:1.3;margin:3px 0}
.streak-label small{color:#897467;display:block}
.week{max-width:100%;gap:5px}
.weekday{font-size:10px;color:#968173}
.daydot{background:#faf1e7;border-color:#f0e2d2;color:#b49a88;width:31px;height:31px;margin:7px auto 0}
.daydot.done{background:#2d9271;color:#fff;border-color:#2d9271}
.daydot.today{box-shadow:0 0 0 3px #ffe1c8}
.path-tile{min-height:248px;border-radius:22px;background:#fffefb}
.path-tile:nth-child(1){background:linear-gradient(150deg,#fffefd,#fff5eb)}
.path-tile:nth-child(2){background:linear-gradient(150deg,#fffefd,#fff8ed)}
.path-tile:nth-child(3){background:linear-gradient(150deg,#fffefd,#f0f9f5)}
.path-icon{height:58px;width:58px;border:1px solid #f0ceb7;background:linear-gradient(145deg,#ffddc4,#fff2e3);border-radius:17px;display:flex;justify-content:center;align-items:center;color:#a44335;font-weight:920;font-size:26px;position:relative}
.path-icon span{font-size:9px;position:absolute;bottom:3px;right:4px}
.path-icon.dev{background:#ddf2e9;color:#2e8269;border-color:#c5e3d5;font-family:serif}
.home-community{background:linear-gradient(120deg,#fffaf3,#fff0e5)}
.home-community .secondary-btn{margin-top:12px}
.book-tile{min-height:204px}
.book-tile.dev-tile{background:linear-gradient(155deg,#fffefd,#fffbf6)}
.version-tile{min-height:265px;background:linear-gradient(140deg,#fffdfb,#fff2e5);position:relative;overflow:hidden}
.version-tile:nth-child(2){background:linear-gradient(140deg,#fffefa,#f4faf5)}
.version-char{font:60px/1.2 ui-serif,STSong,serif;color:#a74534;position:absolute;right:22px;top:15px;opacity:.13;transform:rotate(-14deg)}
.version-tile h3{font-size:31px;letter-spacing:-.04em;margin-top:36px}
.version-tile p{font-size:14px}
.count-tag{font-size:11px;padding:4px 8px;border-radius:50px;color:#936044;background:#fff0e1;vertical-align:middle;margin-left:6px}
.develop-banner{border-radius:21px;background:linear-gradient(110deg,#357f73,#5eaa8a);color:white;padding:27px 32px;display:flex;align-items:center;gap:27px;box-shadow:0 12px 25px #3f957237}
.db-chinese{font:44px/1.2 ui-serif,STSong,serif;white-space:nowrap;opacity:.9}
.develop-banner strong{font-size:17px}
.develop-banner p{margin:7px 0 0;opacity:.85;line-height:1.65;font-size:13px}
/* Contact */
.contact-intro{background:linear-gradient(120deg,#fff0e3,#fffaf3);border:1px solid #f3dfca;border-radius:24px;display:flex;align-items:center;gap:23px;padding:26px;margin-bottom:24px}
.contact-portrait{width:93px;height:93px;flex:none;border-radius:27px;background:#a53d32;display:flex;flex-direction:column;align-items:center;justify-content:center;color:#fff0d9;font:43px/1.1 ui-serif,STSong,serif;box-shadow:0 7px 18px #a64e3c35;transform:rotate(-4deg)}
.contact-portrait span{font:10px Arial,sans-serif;font-weight:900;letter-spacing:.09em;margin-top:4px}
.contact-intro h2{font-size:21px;color:#803d32;margin:10px 0 4px}
.contact-intro p{color:#937462;font-size:13px;margin:3px 0}
.contact-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.contact-card{text-decoration:none;color:#40332e;display:flex;flex-direction:column;gap:7px;border-radius:22px;border:1px solid #edddcf;background:#fffefa;padding:25px 22px;min-height:251px;transition:transform .2s,box-shadow .2s}
.contact-card:hover{transform:translateY(-4px);box-shadow:0 15px 40px #864e3925}
.contact-symbol{height:54px;width:54px;border-radius:16px;display:grid;place-items:center;background:#e6efff;color:#276ad5;font-size:31px;font-weight:920;margin-bottom:6px}
.contact-card.zalo .contact-symbol{color:white;background:#1688f5;font-size:27px}
.contact-card.phone .contact-symbol{color:#267e5f;background:#e5f7ee;font-size:30px}
.contact-eyebrow{font-size:10px;font-weight:900;letter-spacing:.13em;color:#aa8672}
.contact-card h3{font-size:21px;margin:0;color:#4e3832;overflow-wrap:anywhere}
.contact-card p{color:#977e71;font-size:12px;margin:0}
.contact-cta{margin-top:auto;align-self:flex-start;font-weight:850;color:#a24032;font-size:13px}
.contact-card.zalo .contact-cta{color:#2379bd}
.contact-card.phone .contact-cta{color:#218264}
/* tablet */
@media (max-width:1150px){.layout{grid-template-columns:225px minmax(0,1fr)}.sidebar{padding-left:10px;padding-right:10px}.brand{font-size:13px}.brand-mark{height:43px;width:43px}.content{padding:25px 25px 55px}.topbar{padding:15px 25px}.hero{padding:38px 31px;grid-template-columns:1.2fr .75fr}.hero-ink{right:0}.feature-grid{gap:12px}.streak{padding:19px}.quote{padding:22px}}
@media (max-width:790px){.layout{display:block}.sidebar{width:270px;z-index:30;box-shadow:10px 0 40px #322a2624}.overlay.open{z-index:25;background:#241c1b80}.topbar{height:73px;padding:12px 18px;gap:11px}.mobile-wordmark{display:block}.header-right .text-btn{display:none}.topbar .outline-btn{padding:10px 12px}.content{padding:22px 20px 56px}.hero{padding:32px 27px;min-height:325px;grid-template-columns:1fr .72fr}.hero h1{font-size:clamp(29px,4.8vw,42px)}.hero-ink{font-size:195px;right:-8%;}.hero-seal{right:0;bottom:9%}.visual-note{display:none}.feature-grid{grid-template-columns:1fr 1fr}.grid.cols-3{grid-template-columns:repeat(2,minmax(0,1fr))}.contact-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:600px){.topbar{padding:12px 12px;gap:8px}.mobile-wordmark{display:none}.search-form input{font-size:11px;padding:0 4px}.search-form{height:41px}.search-form button{width:34px;height:32px;padding:0;font-size:0}.search-form button:before{content:"→";font-size:19px;position:absolute;inset:0;display:grid;place-items:center}.search-form button{position:relative}.glass{padding-left:10px;font-size:23px}.outline-btn{font-size:11px;padding:8px 10px!important}.content{padding:15px 14px 50px}.hero{grid-template-columns:1fr;padding:28px 24px 20px;min-height:0;border-radius:25px}.hero h1{font-size:clamp(29px,8.1vw,43px);margin:12px 0}.hero-content>p{font-size:13px}.hero-visual{min-height:135px;max-height:135px;overflow:hidden}.hero-ink{font-size:165px;right:11%;top:47%;opacity:.38;transform:translateY(-38%) rotate(-8deg)}.hero-seal{right:5%;bottom:8%;transform:rotate(9deg) scale(.84)}.orbit-one{left:10%;top:23%}.orbit-two{right:22%;top:6%}.orbit-three{left:30%;bottom:10%}.hero-proof{font-size:10px}.hero-actions{margin:18px 0 12px;gap:8px}.hero-primary{font-size:12px;padding:11px 13px}.hero-link{font-size:12px}.feature-grid{grid-template-columns:1fr;margin-top:14px;gap:14px}.quote,.streak{min-height:185px}.streak{padding:19px 19px}.quote{padding:22px 19px}.quote-vi{font-size:21px}.week{gap:3px}.daydot{width:32px;height:32px}.grid.cols-2,.grid.cols-3,.form-grid,.split,.contact-grid{grid-template-columns:1fr}.section-header{margin:30px 0 14px}.section-header h2{font-size:23px}.path-tile{min-height:220px}.grid{gap:12px}.contact-intro{padding:20px;gap:16px}.contact-portrait{width:64px;height:64px;border-radius:20px;font-size:30px}.contact-portrait span{font-size:7px}.contact-intro h2{font-size:17px}.contact-card{min-height:208px}.develop-banner{padding:20px;gap:14px;flex-direction:column;align-items:flex-start}.db-chinese{font-size:33px}.version-tile{min-height:240px}.site-footer{padding:19px 14px;flex-direction:column;align-items:flex-start}.streak .daydot.today{box-shadow:0 0 0 2px #ffe1c8}.nav .nav-leaf{font-size:13px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition-duration:.01ms!important;animation-duration:.01ms!important}}
@media(max-width:600px){.hero h1 span{white-space:nowrap}}

/* V4.1 - quản lý hiển thị bài học; form soạn bài demo */
.publish-status{margin:20px 0;border:1px solid #efcfbe;border-radius:18px;padding:18px 20px;background:#fff9f3}.publish-toggle{display:flex;align-items:flex-start;gap:14px;cursor:pointer}.publish-toggle input{width:22px;height:22px;margin:3px 0 0;accent-color:#a93632;flex:none}.publish-toggle strong{display:block;font-size:16px;color:#3d3330}.publish-toggle small{display:block;margin-top:4px;color:#786b64}.publish-current{margin:14px 0 8px;font-weight:750;color:#a93632;font-size:14px}.publish-status .mini-note{margin:0}