:root{--background-color:#f9fafb;--card-background-color:#ffffff;--border-color:#e5e7eb;--primary-text-color:#111827;--secondary-text-color:#6b7280;--accent-color:#6366f1;--accent-color-hover:#4f46e5;--star-color:#f59e0b}body{background-color:var(--background-color);color:var(--primary-text-color)}.library-wrapper{padding:1rem 0}.library-container{width:90%;max-width:1200px;margin:0 auto}.library-header{text-align:center;padding:2rem 0}.library-header h1{font-size:2.5rem;font-weight:700;color:var(--primary-text-color)}.library-header p{font-size:1.125rem;color:var(--secondary-text-color);margin-top:.5rem}.filters-section{padding:1rem 0;margin-bottom:2rem}.search-wrapper{position:relative;max-width:600px;margin:0 auto}.search-input{width:100%;padding:.75rem 1rem .75rem 2.5rem;background-color:var(--card-background-color);border:1px solid var(--border-color);border-radius:.5rem;color:var(--primary-text-color);font-size:1rem}.search-input::placeholder{color:var(--secondary-text-color)}.search-icon{position:absolute;left:1rem;top:50%;transform:translateY(-50%);color:var(--secondary-text-color)}.lecture-grid{display:grid;grid-template-columns:1fr;gap:1.5rem}.lecture-card{background-color:var(--card-background-color);border-radius:.5rem;overflow:hidden;text-decoration:none;display:flex;flex-direction:column;transition:transform .2s,box-shadow .2s;border:1px solid var(--border-color)}.lecture-card:hover{transform:translateY(-5px);box-shadow:0 10px 15px -3px rgba(0,0,0,7%),0 4px 6px -2px rgba(0,0,0,4%)}.card-image{width:100%;aspect-ratio:16/9;background-color:#e5e7eb}.card-image img{width:100%;height:100%;object-fit:cover}.card-content{padding:1rem;display:flex;flex-direction:column;flex-grow:1}.card-title{font-size:1.25rem;font-weight:600;margin-bottom:.5rem;color:var(--primary-text-color)}.card-lecturer{display:flex;align-items:center;gap:.5rem;margin-bottom:1rem;color:var(--secondary-text-color)}.lecturer-avatar-mini{width:24px;height:24px;border-radius:50%;object-fit:cover}.card-meta{display:flex;justify-content:space-between;color:var(--secondary-text-color);font-size:.875rem;margin-top:auto;padding-top:1rem}.card-meta .rating .fa-star{color:var(--star-color)}.empty-state,.results-counter{text-align:center;padding:2rem 1rem}.empty-state{background-color:var(--card-background-color);border-radius:.5rem;border:1px solid var(--border-color)}.lecturer-hero{padding:3rem 0;background-color:var(--card-background-color);border-bottom:1px solid var(--border-color);margin-bottom:3rem}.lecturer-hero-content{display:flex;flex-direction:column;align-items:center;text-align:center;gap:1.5rem}.lecturer-hero-avatar{width:128px;height:128px;border-radius:50%;overflow:hidden;flex-shrink:0}.lecturer-hero-avatar img{width:100%;height:100%;object-fit:cover}.lecturer-hero-info h1{font-size:2.25rem;font-weight:700}.lecturer-bio{margin-top:1rem;font-size:1.125rem;line-height:1.6;color:var(--secondary-text-color);max-width:65ch}.lecturer-website-link{display:inline-block;margin-top:1.5rem;color:var(--accent-color);text-decoration:none;font-weight:500}.lecturer-website-link:hover{color:var(--accent-color-hover)}.lecture-feed{display:flex;flex-direction:column;gap:3rem;max-width:960px;margin:0 auto}.feed-item{background-color:var(--card-background-color);border-radius:.5rem;border:1px solid var(--border-color);overflow:hidden;text-decoration:none;color:var(--primary-text-color);transition:box-shadow .2s}.feed-item:hover{box-shadow:0 10px 15px -3px rgba(0,0,0,7%),0 4px 6px -2px rgba(0,0,0,4%)}.feed-item-image{width:100%;aspect-ratio:16/9;background-color:#e5e7eb}.feed-item-image img{width:100%;height:100%;object-fit:cover}.feed-item-content{padding:1.5rem}.feed-item-meta{font-size:.875rem;color:var(--secondary-text-color);margin-bottom:.5rem}.feed-item-meta .rating{margin-left:1rem}.feed-item-title{font-size:1.75rem;font-weight:600;margin-bottom:.75rem}.feed-item-description{color:var(--secondary-text-color);margin-bottom:1rem}.feed-item-action{font-weight:500;color:var(--accent-color)}@media(min-width:768px){.lecturer-hero-content{flex-direction:row;text-align:left;gap:3rem}}@media(min-width:640px){.lecture-grid{grid-template-columns:repeat(2,1fr)}}@media(min-width:1024px){.lecture-grid{grid-template-columns:repeat(3,1fr)}}@media(min-width:1280px){.lecture-grid{grid-template-columns:repeat(4,1fr)}}