:root{--primary: #7B1FA2;--primary-light: #9C27B0;--primary-fade: #F3E5F5;--bg-gradient: linear-gradient(180deg, #FDFBFD 0%, #F3E5F5 100%);--success: #2E7D32;--danger: #C62828;--info: #1565C0;--warning: #F9A825;--text-main: #333333;--text-light: #666666;--white: #ffffff;--card-bg: #ffffff;--footer-bg: #111111;--border-color: #eee;--radius: 16px;--shadow: 0 4px 20px rgba(123, 31, 162, .08);--container-width: 1200px}body.dark-mode{--primary: #AB47BC;--primary-light: #E1BEE7;--primary-fade: #2c0b36;--bg-gradient: linear-gradient(180deg, #121212 0%, #1a0520 100%);--text-main: #E0E0E0;--text-light: #B0B0B0;--white: #1E1E1E;--card-bg: #1E1E1E;--border-color: #333;--shadow: 0 4px 20px rgba(0, 0, 0, .5);--footer-bg: #000000}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Open Sans,sans-serif;background:var(--bg-gradient);color:var(--text-main);line-height:1.6;overflow-x:hidden;transition:background .3s,color .3s}h1,h2,h3,h4,h5{font-family:Poppins,sans-serif;color:var(--primary)}a{text-decoration:none;transition:.3s}.progress-container{width:100%;height:5px;background:#0000000d;position:fixed;top:0;left:0;z-index:2000}.progress-bar{height:5px;background:var(--primary);width:0%;transition:width .1s ease-out;box-shadow:0 0 10px var(--primary-light)}header{background:var(--white);box-shadow:0 2px 10px #0000000d;position:sticky;top:0;z-index:1000;padding:1rem 0;transition:background .3s;margin-top:5px}.header-content{max-width:var(--container-width);margin:0 auto;padding:0 1.5rem;display:flex;justify-content:space-between;align-items:center}.logo{font-family:Poppins,sans-serif;font-weight:600;font-size:1.8rem;color:var(--primary);display:flex;align-items:center;gap:8px}.logo-icon{font-family:serif;font-size:2.5rem;font-weight:300;line-height:1;margin-top:-5px}nav ul{display:flex;gap:25px;list-style:none}nav a{color:var(--text-main);font-weight:500;font-size:.95rem}nav a:hover,nav a.active{color:var(--primary);font-weight:600}#theme-toggle{background:none;border:2px solid var(--primary);color:var(--primary);padding:5px 10px;border-radius:20px;cursor:pointer;font-size:1rem;transition:.3s;margin-left:15px}#theme-toggle:hover{background:var(--primary);color:var(--white)}.breadcrumb{max-width:var(--container-width);margin:1.5rem auto 0;padding:0 1.5rem;font-size:.9rem;color:var(--text-light)}.breadcrumb a{color:var(--text-light)}.breadcrumb a:hover{color:var(--primary)}.breadcrumb span{color:var(--primary);font-weight:600}.nav-buttons{display:flex;justify-content:space-between;max-width:var(--container-width);margin:1rem auto;padding:0 1.5rem}.nav-btn{display:inline-flex;align-items:center;background-color:var(--white);color:var(--primary);border:1px solid var(--primary);padding:.6rem 1.2rem;border-radius:30px;font-weight:600;cursor:pointer;transition:all .2s ease;text-decoration:none}.nav-btn:hover{background-color:var(--primary);color:#fff;transform:translateY(-2px);box-shadow:0 4px 10px #7b1fa233}.nav-btn.disabled{opacity:.5;cursor:not-allowed;pointer-events:none;border-color:#ccc;color:#ccc}main{max-width:var(--container-width);margin:1rem auto;padding:0 1.5rem;display:grid;grid-template-columns:1fr;gap:2.5rem;width:100%}.page-title{text-align:center;margin-bottom:2rem}.page-title h1{font-size:2.5rem;margin-bottom:.5rem}.page-title p{color:var(--text-light);font-size:1.1rem}.sj-card{background:var(--card-bg);border-radius:var(--radius);padding:2.5rem;box-shadow:var(--shadow);position:relative;overflow:hidden;border:1px solid var(--border-color);width:100%}.sj-card:before{content:attr(data-step);position:absolute;top:-15px;left:-10px;font-family:Poppins,sans-serif;font-size:7rem;font-weight:900;color:var(--primary);opacity:.07;z-index:0;line-height:1}.card-content{position:relative;z-index:1;width:100%}.calc-box{background:var(--primary-fade);padding:20px;border-radius:12px;text-align:center;margin:20px 0;border:1px solid var(--primary);transition:background .3s}body.dark-mode .calc-box{background:#ab47bc1a;border-color:var(--primary)}.input-group{display:flex;justify-content:center;gap:10px;margin:15px 0;flex-wrap:wrap}.calc-input{padding:10px;border:1px solid #ccc;border-radius:8px;font-size:1rem;text-align:center;width:120px;background:var(--white);color:var(--text-main)}.calc-btn{padding:10px 25px;background:var(--primary);color:#fff;border:none;border-radius:8px;font-weight:600;cursor:pointer;transition:.2s}.calc-btn:hover{background:var(--primary-light);transform:scale(1.05)}.result-panel{background:var(--white);padding:15px;border-radius:8px;margin-top:15px;display:none;font-weight:700;color:var(--primary);border-left:4px solid var(--primary);text-align:left;overflow-wrap:break-word}.box-ncert{background:#f3e5f5;border-left:5px solid var(--primary);padding:1.5rem;border-radius:0 12px 12px 0;margin:1.5rem 0;color:#333}body.dark-mode .box-ncert{background:#2c0b36;color:#e0e0e0}.box-formula{background:#fffde7;border:2px solid var(--warning);padding:1.5rem;border-radius:12px;margin:1.5rem 0;text-align:center;overflow-x:auto;color:#333}body.dark-mode .box-formula{background:#332b00;color:#e0e0e0}.box-pyq{background:#e3f2fd;border-left:5px solid var(--info);padding:1.5rem;margin:1rem 0;border-radius:8px;color:#333}body.dark-mode .box-pyq{background:#0d2538;color:#e0e0e0}.box-mistake{background:#ffebee;border:1px solid var(--danger);color:var(--danger);padding:1rem;border-radius:8px;margin-top:10px}body.dark-mode .box-mistake{background:#360a0a}.box-tip{background:#e8f5e9;border-left:5px solid var(--success);padding:1rem;border-radius:8px;margin-top:10px;color:#333}body.dark-mode .box-tip{background:#0a260e;color:#e0e0e0}.table-responsive{width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch;margin:1rem 0;border-radius:8px}table{width:100%;border-collapse:collapse;min-width:600px}th,td{padding:12px;border:1px solid var(--border-color);text-align:center;vertical-align:middle}th{background:var(--primary);color:#fff;white-space:nowrap}@media(max-width:768px){.table-responsive{overflow-x:visible;border:none}table{min-width:100%;display:block}thead{display:none}tbody,tr,td{display:block}tr{margin-bottom:1.5rem;border:1px solid #e0e0e0;border-radius:12px;background:var(--card-bg);box-shadow:0 4px 6px #0000000d;padding:0;overflow:hidden}td{border:none;border-bottom:1px solid #f0f0f0;position:relative;padding:12px 12px 12px 50%;text-align:right;display:flex;justify-content:flex-end;align-items:center;min-height:40px}td:last-child{border-bottom:none}td:before{content:attr(data-label);position:absolute;left:15px;top:50%;transform:translateY(-50%);width:45%;text-align:left;font-weight:700;color:var(--primary);font-size:.9rem}}.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem}.grid-2>*,.grid-3>*{min-width:0}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem}.step-container{margin-bottom:1rem;border-left:2px solid var(--border-color);padding-left:1rem;transition:background .2s}.step-container:hover{background-color:var(--primary-fade);cursor:pointer}.mark-badge{float:right;background:var(--primary);color:#fff;padding:2px 8px;border-radius:4px;font-size:.8rem;font-weight:700}.quiz-option{display:block;width:100%;text-align:left;background:var(--card-bg);padding:15px;margin:10px 0;border-radius:10px;cursor:pointer;border:1px solid var(--border-color);transition:all .2s;color:var(--text-main);font-family:inherit;font-size:1rem}.quiz-option:hover{background:var(--primary-fade);border-color:var(--primary)}.quiz-option.correct{background:var(--success);color:#fff;border-color:var(--success)}.quiz-option.wrong{background:var(--danger);color:#fff;border-color:var(--danger)}footer{background:var(--footer-bg);color:#ddd;padding:4rem 0 2rem;margin-top:4rem}.footer-grid{max-width:var(--container-width);margin:0 auto;padding:0 1.5rem;display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:2rem}.footer-col h3{color:#fff;margin-bottom:1.5rem;font-size:1.2rem}.footer-col ul{list-style:none}.footer-col li{margin-bottom:.8rem}.footer-col a{color:#aaa;font-size:.9rem}.footer-col a:hover{color:var(--primary-light)}.footer-bottom{text-align:center;border-top:1px solid #333;margin-top:3rem;padding-top:1.5rem;font-size:.85rem;color:#666}mjx-container[display=true]{font-size:105%!important;white-space:normal!important;overflow-x:auto!important;overflow-y:hidden!important;max-width:100%}mjx-container:not([display=true]){overflow:visible!important}body.dark-mode mjx-container{color:#e0e0e0!important}@media(max-width:768px){.header-content{flex-direction:column;gap:1rem}nav ul{gap:10px;flex-wrap:wrap;justify-content:center}main{padding:0 1rem;gap:1.5rem}.sj-card{padding:1.5rem}.grid-2,.grid-3,.footer-grid{grid-template-columns:1fr}.page-title h1{font-size:1.8rem}.step-container{padding-left:.5rem}.footer-col{text-align:center}.mark-badge{float:none;display:inline-block;margin-left:10px}}@keyframes fadeInUp{0%{opacity:0;transform:translateY(28px)}to{opacity:1;transform:translateY(0)}}@keyframes shake{0%,to{transform:translate(0)}20%{transform:translate(-6px)}40%{transform:translate(6px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}@keyframes popIn{0%{transform:scale(.82);opacity:0}70%{transform:scale(1.06);opacity:1}to{transform:scale(1);opacity:1}}.reveal{opacity:1!important;transform:none!important;transition:none!important}.reveal.active{opacity:1!important;transform:none!important}.shake{animation:shake .45s ease-in-out}.pop{animation:popIn .4s cubic-bezier(.175,.885,.32,1.275)}.sj-card{transition:transform .25s ease,box-shadow .25s ease,background .3s}.sj-card:hover{transform:translateY(-3px);box-shadow:0 12px 40px #7b1fa221}.accordion-body{max-height:0;opacity:0;overflow:hidden;transition:max-height .35s ease-out,opacity .3s ease-out,padding .3s ease;padding:0 15px;border-top:1px solid var(--border-color)}.accordion-body.open{max-height:1200px;opacity:1;padding:15px}