.site-header{padding:3rem 2rem 2rem;max-width:1200px;margin:0 auto;display:flex;align-items:flex-end;justify-content:space-between;gap:1rem;flex-wrap:wrap}.site-header h1{font-size:clamp(1.75rem,4vw,2.5rem);font-weight:700;letter-spacing:-.02em;line-height:1.1;background:linear-gradient(135deg,var(--color-text-primary) 40%,var(--color-text-muted));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.site-header p{color:var(--color-text-muted);font-size:.9rem;margin-top:.35rem}.presentation-count{color:var(--color-text-muted);font-size:.85rem;white-space:nowrap;padding-bottom:.25rem}#btn-help{font-size:.85rem;font-weight:600;font-family:var(--font-sans)}#kbd-hint{position:fixed;bottom:4rem;right:1rem;z-index:200}#bottom-bar{position:fixed;bottom:0;left:0;right:0;z-index:100;display:flex;align-items:center;justify-content:flex-end;padding:.6rem 1rem;gap:.5rem;background:#09090bd9;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-top:1px solid var(--color-border)}html.theme-light #bottom-bar{background:#fafafae6}@media(prefers-color-scheme:light){html.theme-system #bottom-bar{background:#fafafae6}}.presentation-count span{color:var(--color-accent);font-weight:600}main{max-width:1200px;margin:0 auto;padding:0 2rem 6rem}.presentations-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:1.25rem}.empty-state{grid-column:1 / -1;text-align:center;padding:4rem 2rem;color:var(--color-text-muted)}.empty-state p{margin-top:.5rem;font-size:.9rem;font-family:var(--font-mono)}.card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-lg);overflow:hidden;display:flex;flex-direction:column;color:inherit;text-decoration:none;cursor:pointer;transition:transform var(--transition-base),box-shadow var(--transition-base),border-color var(--transition-base)}.card:hover{transform:translateY(-2px);box-shadow:var(--shadow-card-hover);border-color:#6366f14d;color:inherit}.card-thumbnail{position:relative;width:100%;aspect-ratio:16 / 9;background:var(--color-border-subtle);overflow:hidden}.card-thumbnail iframe{width:200%;height:200%;transform:scale(.5);transform-origin:top left;pointer-events:none;border:none;opacity:0;transition:opacity var(--transition-slow)}.card-thumbnail iframe.loaded{opacity:1}.card-thumbnail-overlay{position:absolute;top:0;right:0;bottom:0;left:0;background:linear-gradient(to bottom,transparent 60%,rgba(0,0,0,.3))}.card-body{padding:1.25rem;flex:1;display:flex;flex-direction:column;gap:.75rem}.card-title{font-size:1.1rem;font-weight:600;letter-spacing:-.01em;line-height:1.3;color:var(--color-text-primary)}.card-description{font-size:.875rem;color:var(--color-text-muted);line-height:1.5;flex:1;display:-webkit-box;-webkit-line-clamp:2;line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.card-meta{display:flex;align-items:center;gap:.75rem;font-size:.8rem;color:var(--color-text-muted);flex-wrap:wrap}.card-meta-item{display:flex;align-items:center;gap:.3rem}.card-meta-item svg{flex-shrink:0;opacity:.7}.card-author-link{cursor:pointer;transition:color var(--transition-fast)}.card-author-link:hover{color:var(--color-accent)}.card-tags{display:flex;flex-wrap:wrap;gap:.4rem}.tag{display:inline-flex;align-items:center;padding:.2rem .6rem;border-radius:var(--radius-pill);font-size:.75rem;font-weight:500;background:var(--color-tag-bg);border:1px solid var(--color-tag-border);color:var(--color-accent-hover)}.card-footer{padding:0 1.25rem 1.25rem;display:flex;align-items:center;justify-content:space-between;gap:.75rem}.slide-count{font-size:.8rem;color:var(--color-text-muted);font-family:var(--font-mono)}