*{margin:0;padding:0;box-sizing:border-box}
:root{
  --bg:#E7E5E0;      
  --card:#D1C0AA;    
  --accent:#4C2621;  
  --title:#29211A;   
  --text:#29211A;
  --muted:#8D806E;
  --hover:#4C2621;
  --shadow:rgba(41,33,26,.25)
}
body{font-family:'Crimson Text','Georgia',serif;background:var(--bg);color:var(--text);line-height:1.8;min-height:100vh;display:flex;flex-direction:column}
.container{flex:1;max-width:1440px;margin:0 auto;padding:40px 20px}
h1,h2,h3,h4{font-family:'Playfair Display','Georgia',serif;font-weight:700;letter-spacing:-0.4px;color:var(--title)}
h1{font-size:2rem;text-align:center;text-shadow:0 2px 6px rgba(0,0,0,.1);margin-bottom:1.6rem}
h2{font-size:2rem}
.course-selection{padding:80px 20px 60px}
#course-list{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:28px;max-width:1200px;margin:50px auto 0}
.course-card{background:var(--card);border:2px solid var(--accent);border-radius:16px;padding:36px 28px;box-shadow:0 10px 25px var(--shadow);transition:all .4s ease;cursor:pointer;position:relative;overflow:hidden}
.course-card::before{content:'';position:absolute;top:0;left:0;right:0;height:4px;background:var(--accent);transform:scaleX(0);transform-origin:left;transition:transform .5s ease}
.course-card:hover::before{transform:scaleX(1)}
.course-card:hover{transform:translateY(-8px);border-color:var(--accent);box-shadow:0 18px 40px rgba(76,38,33,.3)}
.course-card h3{font-size:1.4rem;margin-bottom:12px;font-style:italic;color:var(--title)}
.course-card p{font-size:1.05rem;background:var(--bg);padding:12px 14px;border-radius:10px;border:1px solid var(--accent)}
.back-btn{background:transparent;color:var(--title);border:2px solid var(--title);padding:12px 24px;border-radius:50px;cursor:pointer;font-weight:600;font-size:1rem;transition:all .4s;display:inline-flex;align-items:center;gap:10px;margin-bottom:20px}
.back-btn:hover{background:var(--accent);color:var(--bg);box-shadow:0 0 20px rgba(76,38,33,.4)}
.layout{display:grid;grid-template-columns:800px 360px;gap:36px;margin-top:24px;min-height:75vh;align-items:start}
.main-content{width:800px;background:var(--card);border-radius:16px;border:1px solid var(--accent);box-shadow:0 12px 30px var(--shadow);padding:44px;display:flex;flex-direction:column;gap:24px}
.sidebar{width:360px;background:var(--card);border-radius:16px;border:1px solid var(--accent);box-shadow:0 12px 30px var(--shadow);overflow-y:auto;max-height:calc(100vh - 200px);padding:0}
#course-title{margin-bottom:0;color:var(--title)}
#content-area{flex:none}
.content-item{margin-bottom:36px}
.content-item h4{font-size:1.55rem;margin:22px 0 14px;position:relative;padding-left:20px;color:var(--title)}
.content-item h4::before{content:'';position:absolute;left:0;top:50%;width:8px;height:8px;background:var(--accent);border-radius:50%;transform:translateY(-50%)}
.content-item p{font-size:1.15rem;background:var(--bg);padding:10px 12px;border-radius:8px;border:1px solid var(--accent)}
.content-item img{max-width:100%;border-radius:10px;margin:24px 0;border:3px solid var(--accent);box-shadow:0 10px 25px var(--shadow)}
.content-item a{color:var(--accent);text-decoration:none;border-bottom:1px dashed var(--accent)}
.content-item a:hover{color:var(--title)}
.pdf-embed{width:100%;height:720px;border:none;border-radius:12px;box-shadow:0 12px 35px var(--shadow);border:1px solid var(--accent)}
.accordion-item{border-bottom:1px solid var(--accent)}
.accordion-header{background:var(--card);color:var(--text);padding:20px 26px;cursor:pointer;font-weight:600;display:flex;justify-content:space-between;align-items:center;transition:background .4s;font-family:'Playfair Display',serif;font-size:1.15rem}
.accordion-header:hover{background:var(--hover);color:var(--bg)}
.accordion-header i{transition:transform .5s ease;color:var(--accent)}
.accordion-content{background:var(--card);max-height:0;overflow:hidden;transition:max-height .6s cubic-bezier(.4,0,.2,1)}
.accordion-content.active{max-height:5000px}
.lecture-item{padding:16px 26px;cursor:pointer;transition:all .3s;font-size:1.05rem;border-bottom:1px solid var(--accent);background:var(--card);color:var(--text)}
.lecture-item:hover{background:var(--hover);padding-left:32px;color:var(--bg)}
.lecture-item.active{color:var(--bg)!important;font-weight:800;background:var(--accent)!important;border-left:4px solid var(--bg)!important}
.sidebar::-webkit-scrollbar{width:6px}
.sidebar::-webkit-scrollbar-thumb{background:var(--muted);border-radius:3px}
.modal{position:fixed;inset:0;background:rgba(41,33,26,.95);backdrop-filter:blur(12px);display:flex;align-items:center;justify-content:center;z-index:1000}
.modal-content{background:var(--card);padding:44px;border-radius:18px;width:90%;max-width:440px;text-align:center;border:2px solid var(--accent);box-shadow:0 25px 60px rgba(76,38,33,.4)}
.modal-content h3{color:var(--title);font-size:2rem;margin-bottom:24px}
#passcode-input{width:100%;padding:18px;margin:18px 0;border:2px solid var(--accent);border-radius:12px;background:var(--bg);color:var(--text);font-size:1.15rem}
#passcode-input:focus{border-color:var(--accent);box-shadow:0 0 0 5px rgba(76,38,33,.2)}
.modal-actions{display:flex;gap:14px;margin-top:28px}
.modal-actions button{flex:1;padding:16px;border:none;border-radius:12px;cursor:pointer;font-weight:600;font-size:1.05rem;background:var(--bg);color:var(--accent);border:2px solid var(--accent)}
.modal-actions button:hover{background:var(--accent);color:var(--bg)}
.error{color:#B80000;margin-top:16px;font-weight:500;font-style:italic}
.hidden{display:none!important}
.site-footer{background:var(--title);border-top:2px solid var(--accent);padding:28px 0;margin-top:100px;color:var(--bg)}
.footer-inner{max-width:1440px;margin:0 auto;text-align:center;display:flex;align-items:center;justify-content:center;gap:22px;flex-wrap:wrap}
.footer-item{color:var(--bg);font-size:1rem}
.footer-item i{margin-right:8px;color:var(--bg)}
.footer-item a{color:var(--bg);text-decoration:none}
.footer-item a:hover{color:var(--accent)}
.footer-separator{color:var(--accent);font-weight:300}
@keyframes fadeIn{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
@media (max-width:992px){.layout{grid-template-columns:1fr}.main-content,.sidebar{width:100%;max-width:none}.sidebar{order:-1;max-height:none}}