.learning-lab{box-sizing:border-box;margin:24px 0;padding:clamp(14px,3vw,24px);border:2px solid #84b9a5;border-radius:18px;background:#f5faf7;color:#1d4053;line-height:1.7;overflow-wrap:anywhere}.learning-lab h2{color:#205f4d;font-size:1.2em;line-height:1.4;margin:0 0 12px}.learning-lab-controls{display:flex;flex-wrap:wrap;gap:18px;margin:18px 0}.learning-lab-controls label{display:grid;flex:1;gap:8px;min-width:min(100%,180px);font-weight:700}.learning-lab-controls input{width:100%;accent-color:#2d8567;min-height:32px}.learning-lab-controls select,.learning-lab-controls button{min-height:44px;max-width:100%;border:1px solid #86acb3;background:white;color:#1d4053;border-radius:10px;padding:10px;font:inherit}.learning-lab-controls button{cursor:pointer}.learning-lab :focus-visible{outline:3px solid #397dc2;outline-offset:3px}.learning-lab svg{display:block;width:100%;height:auto;max-width:620px;margin:auto;background:#eef6f9;border-radius:12px}.learning-lab-answer{font-size:1.1em;font-weight:800;background:#dfefe6;padding:12px;border-radius:10px}.learning-lab li+li{margin-top:10px}.learning-lab-steps{display:flex;gap:10px;flex-wrap:wrap}.learning-lab [aria-pressed=true]{border:2px solid #2d8567;background:#dfefe6}.learning-lab output{font-variant-numeric:tabular-nums}@media(prefers-reduced-motion:reduce){.learning-lab *{animation:none!important;transition:none!important}}
/* BRIGHT-DESIGN:BEGIN yorqin dizayn (fanlar bo‘yicha, body[data-subject]) */
body[data-subject="ona-tili"]{--b1:#ef476f;--b2:#ffb703;--b3:#06b6d4;--bt:#ffe8ee;--bt2:#fff4d6;--rainbow:linear-gradient(90deg,#ef476f,#ffb703,#06b6d4);--grad:linear-gradient(135deg,#ef476f,#ffb703);--deco:"📖 ✏️ 🔤 🗣️";--emo:"✏️"}
@media(prefers-color-scheme:invalid){body[data-subject="ona-tili"]{--b1:#ff8aa6;--bt:color-mix(in srgb,#ef476f 22%,#101827);--bt2:color-mix(in srgb,#ffb703 18%,#101827)}}
body[data-subject="adabiyot"]{--b1:#9b5de5;--b2:#f15bb5;--b3:#fee440;--bt:#f1e6ff;--bt2:#ffe6f5;--rainbow:linear-gradient(90deg,#9b5de5,#f15bb5,#fee440);--grad:linear-gradient(135deg,#9b5de5,#f15bb5);--deco:"📚 🎭 🖋️ 🌙";--emo:"📚"}
@media(prefers-color-scheme:invalid){body[data-subject="adabiyot"]{--b1:#c39bf5;--bt:color-mix(in srgb,#9b5de5 22%,#101827);--bt2:color-mix(in srgb,#f15bb5 18%,#101827)}}
body[data-subject="tarix"]{--b1:#e07a1f;--b2:#c1121f;--b3:#ffc933;--bt:#ffefdc;--bt2:#ffe3e3;--rainbow:linear-gradient(90deg,#e07a1f,#c1121f,#ffc933);--grad:linear-gradient(135deg,#e07a1f,#c1121f);--deco:"🏺 📜 🏰 ⚔️";--emo:"🏺"}
@media(prefers-color-scheme:invalid){body[data-subject="tarix"]{--b1:#ffb066;--bt:color-mix(in srgb,#e07a1f 22%,#101827);--bt2:color-mix(in srgb,#c1121f 18%,#101827)}}
body[data-subject="geografiya"]{--b1:#0ea5e9;--b2:#22c55e;--b3:#ffb703;--bt:#e0f4ff;--bt2:#e3f9ea;--rainbow:linear-gradient(90deg,#0ea5e9,#22c55e,#ffb703);--grad:linear-gradient(135deg,#0ea5e9,#22c55e);--deco:"🌍 🧭 🗺️ 🏔️";--emo:"🌍"}
@media(prefers-color-scheme:invalid){body[data-subject="geografiya"]{--b1:#6cc9f5;--bt:color-mix(in srgb,#0ea5e9 22%,#101827);--bt2:color-mix(in srgb,#22c55e 18%,#101827)}}
body[data-subject="informatika"]{--b1:#4f46e5;--b2:#06b6d4;--b3:#f43f5e;--bt:#e8e7ff;--bt2:#dcf8fd;--rainbow:linear-gradient(90deg,#4f46e5,#06b6d4,#f43f5e);--grad:linear-gradient(135deg,#4f46e5,#06b6d4);--deco:"💻 🤖 ⌨️ 🖱️";--emo:"💻"}
@media(prefers-color-scheme:invalid){body[data-subject="informatika"]{--b1:#8f89f5;--bt:color-mix(in srgb,#4f46e5 22%,#101827);--bt2:color-mix(in srgb,#06b6d4 18%,#101827)}}
body[data-subject="oqish"]{--b1:#e11d74;--b2:#ff8a3d;--b3:#ffd23f;--bt:#ffe3ef;--bt2:#fff0e0;--rainbow:linear-gradient(90deg,#e11d74,#ff8a3d,#ffd23f);--grad:linear-gradient(135deg,#e11d74,#ff8a3d);--deco:"📕 🌟 🎈 🐞";--emo:"📕"}
@media(prefers-color-scheme:invalid){body[data-subject="oqish"]{--b1:#ff6fa8;--bt:color-mix(in srgb,#e11d74 22%,#101827);--bt2:color-mix(in srgb,#ff8a3d 18%,#101827)}}
body[data-subject="texnologiya"]{--b1:#f97316;--b2:#0ea5e9;--b3:#84cc16;--bt:#ffeedd;--bt2:#e0f4ff;--rainbow:linear-gradient(90deg,#f97316,#0ea5e9,#84cc16);--grad:linear-gradient(135deg,#f97316,#0ea5e9);--deco:"🛠️ 🧵 🍳 🌱";--emo:"🛠️"}
@media(prefers-color-scheme:invalid){body[data-subject="texnologiya"]{--b1:#ffa461;--bt:color-mix(in srgb,#f97316 22%,#101827);--bt2:color-mix(in srgb,#0ea5e9 18%,#101827)}}
body[data-subject="ingliz-tili"]{--b1:#2563eb;--b2:#ec4899;--b3:#fbbf24;--bt:#e3ecff;--bt2:#ffe6f2;--rainbow:linear-gradient(90deg,#2563eb,#ec4899,#fbbf24);--grad:linear-gradient(135deg,#2563eb,#ec4899);--deco:"🇬🇧 💬 🎧 🔤";--emo:"💬"}
@media(prefers-color-scheme:invalid){body[data-subject="ingliz-tili"]{--b1:#7aa5f7;--bt:color-mix(in srgb,#2563eb 22%,#101827);--bt2:color-mix(in srgb,#ec4899 18%,#101827)}}
@keyframes brbf{0%,100%{transform:translate(0,0)scale(1)}50%{transform:translate(22px,-26px)}}
@keyframes brpop{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
body{background-image:radial-gradient(color-mix(in srgb,var(--b1) 14%,transparent) 1.6px,transparent 1.8px),radial-gradient(900px 420px at 8% -80px,var(--bt),transparent 70%),radial-gradient(800px 380px at 100% -60px,var(--bt2),transparent 70%)!important;background-size:26px 26px,auto,auto!important;background-attachment:fixed}
body::before,body::after{content:"";position:fixed;z-index:-1;border-radius:50%;pointer-events:none;animation:brbf 14s ease-in-out infinite}
body::before{width:340px;height:340px;right:-90px;top:30%;background:radial-gradient(circle,color-mix(in srgb,var(--b2) 30%,transparent),transparent 70%)}
body::after{width:420px;height:420px;left:-140px;bottom:-60px;background:radial-gradient(circle,color-mix(in srgb,var(--b3) 28%,transparent),transparent 70%);animation-delay:-6s}
.course-header{background:color-mix(in srgb,var(--surface,#fff) 92%,transparent)!important;backdrop-filter:blur(10px);border-bottom:0!important;box-shadow:0 6px 20px color-mix(in srgb,var(--b1) 16%,transparent);padding-block:14px!important}
.course-header a{color:var(--b1)!important;font-weight:800}
#subject-name{font-size:1.5rem;font-weight:900}
#subject-name::before{content:var(--emo);margin-right:.35rem}
.course-hero{position:relative;overflow:hidden;background:linear-gradient(125deg,var(--b1),color-mix(in srgb,var(--b1) 45%,var(--b2)) 55%,var(--b2))!important;border:0!important;border-radius:30px!important;color:#fff!important;box-shadow:0 22px 50px color-mix(in srgb,var(--b1) 40%,transparent)}
.course-hero *{color:#fff!important}
.course-hero h1{text-shadow:0 3px 14px rgba(0,0,0,.22)}
.course-hero::before{content:"";position:absolute;width:320px;height:320px;right:-60px;top:-90px;border-radius:50%;background:radial-gradient(circle,rgba(255,255,255,.35),transparent 70%);pointer-events:none}
.course-hero::after{content:var(--deco);position:absolute;right:5%;bottom:10%;font-size:2.4rem;letter-spacing:.9rem;opacity:1;pointer-events:none;animation:brbf 11s ease-in-out infinite}
.course-hero .button,.course-hero a.primary{background:#fff!important;color:var(--b1)!important;border:0!important;box-shadow:0 8px 20px rgba(0,0,0,.2)}
.button,a.button,.primary{border-radius:999px!important;font-weight:800;transition:transform .15s,box-shadow .15s}
a.primary,.button.primary,.practice-start .primary{background:var(--grad)!important;color:#fff!important;border:0!important;box-shadow:0 8px 20px color-mix(in srgb,var(--b1) 38%,transparent)!important}
@media(hover:hover){.button:hover,a.primary:hover{transform:translateY(-2px)}}
.lesson-grid{gap:18px}
.lesson-card,.toc-card{border:2px solid color-mix(in srgb,var(--b1) 16%,transparent)!important;border-top:6px solid var(--b1)!important;border-radius:22px!important;box-shadow:0 10px 26px color-mix(in srgb,var(--b1) 14%,transparent)!important;animation:brpop .45s ease both}
.lesson-card:nth-child(4n+1){background:linear-gradient(150deg,var(--b1),color-mix(in srgb,var(--b1) 40%,var(--b2)))!important;color:#fff!important;border:0!important}
.lesson-card:nth-child(4n+2){background:linear-gradient(150deg,var(--b2),color-mix(in srgb,var(--b2) 50%,var(--b1)))!important;color:#fff!important;border:0!important}
.lesson-card:nth-child(4n+3){background:linear-gradient(150deg,var(--b3),color-mix(in srgb,var(--b3) 55%,#ff5e8a))!important;color:#102030!important;border:0!important}
.lesson-card:nth-child(4n){background:linear-gradient(150deg,color-mix(in srgb,var(--b1) 60%,#ff5e8a),var(--b1))!important;color:#fff!important;border:0!important}
.lesson-card *{color:inherit!important}
.grade-bubble,.book-cover{background:rgba(255,255,255,.92)!important;color:var(--b1)!important;border-radius:16px!important;font-weight:900}
.book-progress{background:rgba(255,255,255,.4)!important;border-radius:999px}
@media(hover:hover){.lesson-card:hover{transform:translateY(-6px) ;box-shadow:0 18px 38px color-mix(in srgb,var(--b1) 30%,transparent)!important}.toc-card:hover{transform:translateX(6px)}}
.toc-list{display:grid;gap:.7rem}
.toc-card{border-top-width:2px!important;border-left:8px solid var(--b1)!important;background:linear-gradient(135deg,var(--bt),transparent 65%),var(--surface,#fff)!important}
.toc-card:nth-child(3n+2){border-left-color:var(--b2)!important}.toc-card:nth-child(3n){border-left-color:var(--b3)!important}
.toc-number{background:var(--grad)!important;color:#fff!important;border-radius:14px!important;font-weight:900}
.toc-state{background:var(--bt)!important;color:var(--b1)!important;border-radius:999px!important;font-weight:800}
.chapter-nav .filter,button.filter{border-radius:999px!important;border:2px solid color-mix(in srgb,var(--b1) 30%,transparent)!important;font-weight:800;background:var(--surface,#fff)}
.chapter-nav .filter[aria-pressed=true],.filter.active{background:var(--grad)!important;color:#fff!important;border-color:transparent!important}
.chapter-heading h2,h1,h2{color:var(--b1)}
h2::after{content:"";display:block;width:70px;height:6px;border-radius:6px;margin-top:.35rem;background:var(--rainbow)}
.lesson-panel,section.worked,.lesson-illustration,.practice-start,.curriculum-status,.course-facts,section.chapter{border:2px solid color-mix(in srgb,var(--b1) 18%,transparent)!important;border-left:8px solid var(--b1)!important;border-radius:20px!important;background:linear-gradient(135deg,var(--bt),transparent 60%),var(--surface,#fff)!important;box-shadow:0 8px 22px color-mix(in srgb,var(--b1) 11%,transparent)}
.worked{border-left-color:var(--b2)!important}.practice-start{border-left-color:var(--b3)!important}
.language-token{border-radius:16px!important;box-shadow:0 6px 16px color-mix(in srgb,var(--b1) 14%,transparent)}
.eyebrow,.lesson-route{color:var(--b1)!important;font-weight:800}
input[type=search],input,select{border:2px solid color-mix(in srgb,var(--b1) 30%,transparent)!important;border-radius:14px!important;min-height:44px}
input:focus,select:focus,a:focus-visible,button:focus-visible{outline:3px solid var(--b3)!important;outline-offset:3px}
button.option{border-radius:16px;border:2px solid color-mix(in srgb,var(--b1) 25%,transparent);font-weight:700}
progress{-webkit-appearance:none;appearance:none;height:14px;border:0;border-radius:999px;background:var(--bt);overflow:hidden}
progress::-webkit-progress-bar{background:var(--bt)}progress::-webkit-progress-value{background:var(--rainbow);border-radius:999px}
.lesson-panel p,.worked p{max-width:68ch;line-height:1.85}
html{scroll-behavior:smooth}
::-webkit-scrollbar{width:12px;height:12px}::-webkit-scrollbar-thumb{background:var(--grad);border-radius:999px;border:3px solid transparent;background-clip:padding-box}::-webkit-scrollbar-track{background:var(--bt)}
a,button,.button{min-height:40px}
@media(max-width:640px){.course-header{gap:10px;padding-inline:4%!important}.course-hero{border-radius:22px!important}.course-hero::after{display:none}.course-controls{width:100%}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}
@media print{body{background:#fff!important}body::before,body::after,.course-hero::before,.course-hero::after{display:none!important}*{animation:none!important;box-shadow:none!important}}
.lesson-card p,.lesson-card span:not(.grade-bubble){font-weight:600}
.course-hero .course-facts{background:rgba(255,255,255,.2)!important;border:0!important;box-shadow:none!important;backdrop-filter:blur(4px)}.course-hero .course-facts *{background:transparent!important;color:#fff!important;border:0!important;box-shadow:none!important}.course-hero::after{bottom:auto;top:10%}
.options{border:0!important;box-shadow:none!important;background:none!important}button.option>b{display:inline-grid;place-items:center;min-width:2.1rem;height:2.1rem;border-radius:12px;background:var(--grad)!important;color:#fff!important}@media(hover:hover){button.option:hover{border-color:var(--b1);background:var(--bt)}}button.option[aria-pressed=true]{background:var(--grad)!important;color:#fff!important;border-color:transparent}button.option.correct{background:linear-gradient(135deg,#1fb56b,#7ee08b)!important;color:#fff!important}button.option.wrong{background:linear-gradient(135deg,#ef4d5e,#ff9a76)!important;color:#fff!important}
html,body{min-height:100vh}

.course-header{border-bottom:5px solid transparent!important;border-image:var(--rainbow) 1!important}


/* bir xil yuqori panel: logotip + fan nomi + Menyu (Matematika/Fizika/Kimyo/Biologiya bilan bir xil) */
.bt-util{display:flex;align-items:center;gap:8px;padding:8px 10px;background:var(--surface,#fff);border-bottom:1px solid var(--line,#e1e8f2);min-height:64px}
.bt-btn{display:inline-flex;align-items:center;gap:10px;min-height:56px;padding:0 18px;border:1px solid #c9d3dc;border-radius:14px;background:var(--surface,#fff);color:var(--ink,#1c2a3a);font:inherit;font-weight:400;text-decoration:none;cursor:pointer;box-sizing:border-box}
.bt-home{font-size:16px;font-weight:500}.bt-home svg{width:28px;height:28px}
.bt-set{font-size:20px}.bt-set span:first-child{font-size:18px}
.bt-btn:hover{border-color:var(--b1);background:var(--bt)}
.bt-ic{width:56px;height:56px;min-height:56px;padding:0;border-radius:14px;display:grid;place-items:center;overflow:hidden;cursor:pointer;box-sizing:border-box;color:var(--b1);background:var(--surface,#fff);border:1px solid #c9d3dc}
.bt-pink{background:#fff0f5;border-color:#f5c8d8}.bt-blue{background:#e8f6ff;border-color:#bfe3f5}
.bt-ic img{width:30px;height:30px;display:block}
.bt-spacer{flex:1}
.bt-panel,.bt-menu{display:flex;align-items:center;flex-wrap:wrap;gap:12px;padding:12px max(16px,calc((100% - 1350px)/2));background:var(--bt);border-bottom:1px solid var(--line,#e1e8f2)}
.bt-panel[hidden],.bt-menu[hidden]{display:none}
.bt-links{display:flex;gap:10px;flex-wrap:wrap}
.bt-links a{display:inline-flex;align-items:center;min-height:44px;padding:0 16px;border-radius:999px;background:var(--surface,#fff);border:2px solid color-mix(in srgb,var(--b1) 30%,transparent);color:var(--b1);font-weight:800;text-decoration:none}
.bt-links a:hover{background:var(--grad);color:#fff}
.course-header{display:flex!important;align-items:center;justify-content:space-between;gap:14px;padding:6px max(16px,calc((100% - 1350px)/2))!important;min-height:84px}
.bt-brand{display:flex;align-items:center;gap:14px}
.bt-logo{width:80px;height:61px;object-fit:contain;display:block}
.bt-brandtext small{display:block;color:var(--muted,#58698a);font-size:1rem;font-weight:500;line-height:1.1}
#subject-name{display:block!important;font-size:2.3rem!important;font-weight:800!important;line-height:1.1;color:var(--ink,#1c2a3a)!important;letter-spacing:-.02em;text-decoration:none}
#subject-name::before,#subject-name::after{content:none!important;display:none!important}
.bt-menu-btn{display:inline-flex;align-items:center;gap:10px;min-height:56px;padding:0 20px;border:0;border-radius:16px;background:var(--grad);color:#fff;font:inherit;font-size:1.05rem;font-weight:800;cursor:pointer;box-shadow:0 8px 20px color-mix(in srgb,var(--b1) 38%,transparent)}
.bt-menu-btn:hover{transform:translateY(-2px)}
.bt-chev{font-size:1.2rem;line-height:1;transform:translateY(-3px)}
.bt-search{display:flex;align-items:center;gap:12px}
.study-wayfinding{justify-content:center}
@media(max-width:700px){.bt-util{flex-wrap:wrap}.bt-home{font-size:15px}.bt-set{font-size:17px}.course-header{gap:8px;min-height:72px}#subject-name{font-size:1.7rem!important}.bt-logo{width:60px;height:46px}.bt-menu-btn{padding:0 14px}}
/* aniq o‘lchamlar: Matematika paneli bilan piksel-piksel mos */
.bt-util{padding:5px 12px!important;min-height:56px!important;gap:6px!important;border-bottom:1px solid var(--line,#e5e9f2)}
.bt-home{min-height:44px!important;height:44px;padding:8px 12px!important;font-size:13px!important;font-weight:400!important;border-radius:12px!important;gap:8px}
.bt-home svg{width:24px!important;height:24px!important}
.bt-set{min-height:47px!important;height:47px;padding:8px 12px!important;font-size:17px!important;font-weight:400!important;border-radius:10px!important;gap:6px}
.bt-set span:first-child{font-size:15px!important}
.bt-ic{width:44px!important;height:44px!important;min-height:44px!important;border-radius:12px!important}
.bt-ic img{width:24px!important;height:24px!important}
.bt-ic svg{width:22px!important;height:22px!important}
.bt-find{border-color:#dbe2ef!important}
.course-header{padding:0 max(20px,calc((100% - 1120px)/2 + 20px))!important;min-height:69px!important}
.bt-brand{gap:10px!important}
.bt-logo{width:64px!important;height:50px!important}
.bt-brandtext small{font-size:13px!important;font-weight:400!important;color:#4b5968!important;line-height:20px!important}
#subject-name{font-size:28px!important;font-weight:800!important;line-height:34px!important;color:#202a35!important}
.bt-menu-btn{min-height:44px!important;height:44px;padding:8px 12px!important;border-radius:14px!important;font-size:14px!important;font-weight:600!important;gap:8px!important;box-shadow:0 6px 16px color-mix(in srgb,var(--b1) 35%,transparent)}
.bt-menu-btn svg{width:20px;height:20px}
.bt-panel,.bt-menu{padding:10px max(20px,calc((100% - 1120px)/2 + 20px))!important}
@media(max-width:700px){#subject-name{font-size:22px!important;line-height:26px!important}.bt-logo{width:52px!important;height:40px!important}.course-header{min-height:60px!important}}
.bt-util{height:56px!important;box-sizing:border-box}
.bt-menu-btn{gap:6px!important}.bt-menu-btn svg{width:18px!important;height:18px!important}.bt-chev{font-size:1rem!important}
/* ANIQLIK: tugma qirralari, yozuv va rasmlar tiniq. */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
body{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;text-rendering:optimizeLegibility;font-weight:500}
img,svg,canvas,video{image-rendering:auto;filter:none!important;backface-visibility:hidden}
button,.btn,.button,a.button,a.btn,select,input,textarea,.bt-btn,.settings-launcher,.search-launcher,.community-shortcut,.menu-toggle,.filter,.option,button.option{
 border-width:2px!important;border-style:solid;font-weight:600}
button:not(.primary):not(.bt-menu-btn):not(.bt-pink):not(.bt-blue):not([class*=primary]),.btn:not(.primary),.button:not(.primary),a.button:not(.primary),.bt-btn,.bt-ic,.settings-launcher,.search-launcher,.menu-toggle,select,input,textarea,.filter,button.option{
 border-color:color-mix(in srgb,currentColor 55%,transparent)!important}
.bt-pink,.community-shortcut[data-ui-icon=support]{border-color:#e08aaa!important}
.bt-blue,.community-shortcut[data-ui-icon=contact]{border-color:#7cc0e6!important}
.primary,.btn.primary,.button.primary,.bt-menu-btn,.menu-toggle{border-color:transparent!important}
.bt-home,.bt-btn,.bt-ic{font-weight:600!important;box-shadow:none}
.bt-home{font-size:14px!important}
button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #ffb020!important;outline-offset:2px}
input,select,textarea{font-weight:500}
small,.muted,.caption{font-weight:500}
.search input,.search input[type=search]{border:0!important}

.bt-home{padding:5px 12px 5px 6px!important}.bt-home .ilmdosh-mark{width:34px;height:34px;display:block;flex:none}
.bt-logo{width:56px!important;height:56px!important;border-radius:16px}
@media(max-width:700px){.bt-logo{width:44px!important;height:44px!important}}

/* YOPISHQOQ: Ilmdosh belgisi (chap) va qidiruv (o‘ng) har doim ko‘rinib turadi */
.bt-util{position:relative!important;z-index:80;box-shadow:0 2px 10px rgba(20,30,60,.08)}
.course-header{position:relative!important;z-index:70;background:var(--surface,#fff)!important}
.bt-panel{position:fixed!important;left:0;right:0;top:var(--bt-u,56px);z-index:90;box-shadow:0 14px 30px rgba(20,30,60,.18)}
.bt-menu{position:fixed!important;left:0;right:0;top:calc(var(--bt-u,56px) + var(--bt-h,69px));z-index:85;max-height:calc(100vh - var(--bt-u,56px) - var(--bt-h,69px));overflow:auto;box-shadow:0 18px 36px rgba(20,30,60,.2);border-top:3px solid var(--b1)}
.bt-menu[hidden],.bt-panel[hidden]{display:none!important}
.bt-menu{display:grid!important;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px 24px;align-items:center;padding:16px max(20px,calc((100% - 1120px)/2 + 20px))!important}
.bt-menu[hidden]{display:none!important}
.bt-menu .bt-search{grid-column:1/-1}
.bt-links{display:contents}
.bt-links a{border:0!important;border-radius:14px!important;background:transparent!important;color:var(--ink,#1c2a3a)!important;font-weight:600!important;font-size:1rem;min-height:52px;gap:12px;padding:0 10px!important}
.bt-links a span{display:grid;place-items:center;width:40px;height:40px;border-radius:12px;background:var(--bt);font-size:1.25rem}
.bt-links a:hover{background:var(--bt)!important;color:var(--b1)!important}
@media(max-width:800px){.bt-menu{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:700px){
 .bt-util{flex-wrap:nowrap!important;overflow:hidden}
 .bt-home span:last-child,.bt-set span:last-child{display:none}
 .bt-home,.bt-set{padding:5px 8px!important}
 .course-header{position:static!important}
 .bt-menu{position:fixed!important;top:var(--bt-u,56px)!important;max-height:calc(100vh - var(--bt-u,56px));grid-template-columns:1fr}
}




/* ZICH PANEL: pastga surilganda panel yashirinadi, faqat kichik qidiruv belgisi qoladi */
.bt-util,.course-header{transition:transform .25s ease,background .2s}
html.hdr-compact .bt-util{pointer-events:none;background:transparent!important;border-color:transparent!important;box-shadow:none!important;justify-content:flex-end}
html.hdr-compact .bt-util>*:not(.bt-find){display:none!important}
html.hdr-compact .bt-find{pointer-events:auto;width:40px!important;height:40px!important;min-height:40px!important;background:var(--surface,#fff);box-shadow:0 4px 14px rgba(20,30,60,.25)}
html.hdr-compact .course-header{transform:translateY(calc(-100% - 90px));box-shadow:none}
html.hdr-compact.hdr-up .course-header{transform:none;top:0!important;box-shadow:0 8px 24px rgba(20,30,60,.18)}
html.hdr-compact .bt-menu{top:56px!important;max-height:calc(100vh - 56px)}
html.hdr-compact.hdr-up .bt-menu{top:var(--bt-h,69px)!important;max-height:calc(100vh - var(--bt-h,69px))}
html.hdr-compact .bt-panel{top:0!important}
@media(max-width:700px){html.hdr-compact.hdr-up .course-header{position:sticky!important;left:0;right:0;padding-right:60px!important}}

.brandbar{position:fixed;top:0;left:0;right:64px;z-index:75;display:none;align-items:center;gap:10px;height:56px;padding:0 14px;background:#fff;color:#101828;text-decoration:none;border-bottom:1px solid #e3e7f0;box-shadow:0 6px 18px rgba(16,24,40,.14);font:800 20px/1 Nunito,system-ui,sans-serif;-webkit-text-fill-color:#101828}
.brandbar.on{display:flex}
.brandbar img{width:40px;height:40px;border-radius:12px;flex:none}
.brandbar span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.brandbar:active{background:#eef0fd}
@media print{.brandbar{display:none!important}}
/* ZICH-END */
/* STICKY-ONLY-COMPACT */
html.hdr-compact .bt-util{position:sticky!important;top:0}
html.hdr-compact .course-header{position:sticky!important;top:0!important}
.bt-logo-link{display:block;line-height:0}
/* HDR-END */
/* ===== PRO:BEGIN ===== */
html:not([data-stil="yorqin"]) body{background:#f6f7fb!important;background-image:none!important}
html:not([data-stil="yorqin"]) body::before,html:not([data-stil="yorqin"]) body::after{display:none!important}
html:not([data-stil="yorqin"]) .bt-util,html:not([data-stil="yorqin"]) .course-header{box-shadow:none!important}
html:not([data-stil="yorqin"]) .course-header{border-bottom:1px solid #e3e7f0!important;border-image:none!important}
html:not([data-stil="yorqin"]) .bt-util{border-bottom:1px solid #e3e7f0!important}
html:not([data-stil="yorqin"]) h2::after{display:none!important}
html:not([data-stil="yorqin"]) .course-hero{background:linear-gradient(135deg,var(--b1),color-mix(in srgb,var(--b1) 72%,#000))!important;box-shadow:0 14px 34px color-mix(in srgb,var(--b1) 26%,transparent)!important}
html:not([data-stil="yorqin"]) .course-hero::before,html:not([data-stil="yorqin"]) .course-hero::after{display:none!important}
html:not([data-stil="yorqin"]) .lesson-card,html:not([data-stil="yorqin"]) .lesson-card:nth-child(n){background:#fff!important;color:#101828!important;border:1px solid #e3e7f0!important;border-top:3px solid var(--b1)!important;box-shadow:0 1px 2px rgba(16,24,40,.04),0 10px 26px rgba(16,24,40,.06)!important;animation:none!important}
html:not([data-stil="yorqin"]) .lesson-card *{color:inherit!important}
html:not([data-stil="yorqin"]) .lesson-card h2,html:not([data-stil="yorqin"]) .lesson-card h3{color:#101828!important}
html:not([data-stil="yorqin"]) .lesson-card .grade-bubble,html:not([data-stil="yorqin"]) .lesson-card .book-cover{background:var(--b1)!important;color:#fff!important}
html:not([data-stil="yorqin"]) .lesson-card:hover{transform:translateY(-4px)!important;box-shadow:0 2px 4px rgba(16,24,40,.05),0 18px 40px rgba(16,24,40,.12)!important}
html:not([data-stil="yorqin"]) .lesson-card .book-progress{background:#e7eaf3!important}
html:not([data-stil="yorqin"]) .toc-card{background:#fff!important;border:1px solid #e3e7f0!important;border-left:4px solid var(--b1)!important;box-shadow:none!important;animation:none!important}
html:not([data-stil="yorqin"]) .toc-card:nth-child(n){border-left-color:var(--b1)!important}
html:not([data-stil="yorqin"]) .lesson-panel,html:not([data-stil="yorqin"]) section.worked,html:not([data-stil="yorqin"]) .lesson-illustration,html:not([data-stil="yorqin"]) .practice-start,html:not([data-stil="yorqin"]) .curriculum-status,html:not([data-stil="yorqin"]) .course-facts,html:not([data-stil="yorqin"]) section.chapter{background:#fff!important;border:1px solid #e3e7f0!important;border-left:4px solid var(--b1)!important;box-shadow:0 1px 2px rgba(16,24,40,.04)!important}
html:not([data-stil="yorqin"]) .worked{border-left-color:var(--b2)!important}html:not([data-stil="yorqin"]) .practice-start{border-left-color:var(--b3)!important}
html:not([data-stil="yorqin"]) a.primary,html:not([data-stil="yorqin"]) .button.primary,html:not([data-stil="yorqin"]) .practice-start .primary{background:var(--b1)!important;box-shadow:0 6px 16px color-mix(in srgb,var(--b1) 28%,transparent)!important}
html:not([data-stil="yorqin"]) .bt-menu-btn,html:not([data-stil="yorqin"]) .menu-toggle{background:var(--b1)!important;box-shadow:none!important}
html:not([data-stil="yorqin"]) .chapter-nav .filter[aria-pressed=true],html:not([data-stil="yorqin"]) .filter.active{background:var(--b1)!important}
html:not([data-stil="yorqin"]) ::-webkit-scrollbar-thumb{background:#c3cbe3!important}
/* ===== PRO:END ===== */
/* ===== BTN:BEGIN aniq tugmalar ===== */
body{--bd:color-mix(in srgb,var(--b1) 74%,#000)}
html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .bt-menu-btn,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .menu-toggle,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) a.primary,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .button.primary{background:var(--bd)!important;color:#fff!important;-webkit-text-fill-color:#fff!important;border:2px solid color-mix(in srgb,var(--bd) 70%,#000)!important;box-shadow:0 3px 0 color-mix(in srgb,var(--bd) 60%,#000)!important}
html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero a.button,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero .button{background:#fff!important;color:var(--bd)!important;-webkit-text-fill-color:var(--bd)!important;border:2px solid #fff!important;box-shadow:0 3px 0 rgba(0,0,0,.28)!important;font-weight:800!important}
html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero a.primary,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero .button.primary{background:#ffb020!important;color:#1b1300!important;-webkit-text-fill-color:#1b1300!important;border:2px solid #fff3c4!important}
html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero a.button *,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .course-hero .button *{color:inherit!important;-webkit-text-fill-color:inherit!important}
html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .button,html:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) a.button{min-height:44px}
/* ===== BTN:END ===== */
/* NOLINE:BEGIN */
html.hdr-compact:not([data-stil="x1"]):not([data-stil="x2"]):not([data-stil="x3"]) .bt-util{border:0!important;box-shadow:none!important;background:transparent!important}
/* NOLINE:END */
/* TOC-STATIC:BEGIN */
.toc-toolbar{position:static!important;top:auto!important;background:transparent!important;border-bottom:0!important;padding:0!important;z-index:auto!important}
/* TOC-STATIC:END */
/* BRIGHT-DESIGN:END */

/* Keep quiz answers stationary when focus/hover moves between questions. */
.options button.option,.options button.option:hover,.options button.option:active{transform:none!important;transition:none!important}