:root{--bg:#0a0b0f;--surface:#12141c;--surface2:#1a1d28;--border:#2a2d3a;--text:#e8e6e3;--text-dim:#8b8d97;--accent:#ff6b35;--accent2:#00d4aa;--accent3:#6c63ff;--accent4:#ff4081;--obsolete:#ff4444;--legacy:#ff9800;--current:#4caf50;--cutting:#00bcd4;--future:#9c27b0;--lossless:#64b5f6}
*{margin:0;padding:0;box-sizing:border-box}
body{background:var(--bg);color:var(--text);font-family:'DM Sans',sans-serif;line-height:1.6;overflow-x:hidden}
.hero{min-height:55vh;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;padding:4rem 2rem;position:relative;overflow:hidden}
.hero::before{content:'';position:absolute;inset:0;background:radial-gradient(ellipse 800px 400px at 30% 50%,rgba(255,107,53,.08),transparent),radial-gradient(ellipse 600px 400px at 70% 40%,rgba(108,99,255,.06),transparent),radial-gradient(ellipse 500px 300px at 50% 80%,rgba(0,212,170,.05),transparent);pointer-events:none}
.hero-label{font-family:'JetBrains Mono',monospace;font-size:.75rem;letter-spacing:.2em;text-transform:uppercase;color:var(--accent);margin-bottom:1.5rem;opacity:0;animation:fadeUp .8s ease forwards .2s}
.hero h1{font-family:'Instrument Serif',serif;font-size:clamp(2.8rem,7vw,5.5rem);font-weight:400;line-height:1.1;letter-spacing:-.02em;max-width:800px;opacity:0;animation:fadeUp .8s ease forwards .4s}
.hero h1 em{font-style:italic;color:var(--accent)}
.hero-sub{font-size:1.1rem;color:var(--text-dim);max-width:600px;margin-top:1.5rem;opacity:0;animation:fadeUp .8s ease forwards .6s}
@keyframes fadeUp{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}
.nav-bar{position:sticky;top:0;z-index:100;background:rgba(10,11,15,.85);backdrop-filter:blur(20px);border-bottom:1px solid var(--border);padding:0 2rem}
.nav-inner{max-width:1200px;margin:0 auto;display:flex;overflow-x:auto;scrollbar-width:none}.nav-inner::-webkit-scrollbar{display:none}
.nav-tab{padding:1rem 1.5rem;font-family:'JetBrains Mono',monospace;font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;color:var(--text-dim);cursor:pointer;white-space:nowrap;border:none;border-bottom:2px solid transparent;background:none;transition:all .3s ease}
.nav-tab:hover{color:var(--text)}.nav-tab.active{color:var(--accent);border-bottom-color:var(--accent)}
.section{max-width:1200px;margin:0 auto;padding:4rem 2rem;display:none}.section.active{display:block}
.section-title{font-family:'Instrument Serif',serif;font-size:2.5rem;margin-bottom:.5rem}
.section-desc{color:var(--text-dim);margin-bottom:3rem;max-width:700px}
.badge{display:inline-flex;align-items:center;gap:.35rem;padding:.25rem .7rem;border-radius:100px;font-family:'JetBrains Mono',monospace;font-size:.65rem;letter-spacing:.05em;text-transform:uppercase;font-weight:600}
.badge::before{content:'';width:6px;height:6px;border-radius:50%}
.badge-obsolete{background:rgba(255,68,68,.12);color:var(--obsolete)}.badge-obsolete::before{background:var(--obsolete)}
.badge-legacy{background:rgba(255,152,0,.12);color:var(--legacy)}.badge-legacy::before{background:var(--legacy)}
.badge-current{background:rgba(76,175,80,.12);color:var(--current)}.badge-current::before{background:var(--current)}
.badge-cutting{background:rgba(0,188,212,.12);color:var(--cutting)}.badge-cutting::before{background:var(--cutting)}
.badge-future{background:rgba(156,39,176,.12);color:var(--future)}.badge-future::before{background:var(--future)}
.badge-lossless{background:rgba(100,181,246,.12);color:var(--lossless)}.badge-lossless::before{background:var(--lossless)}
.legend{display:flex;flex-wrap:wrap;gap:.6rem;margin-bottom:2rem;padding:1rem 1.25rem;background:var(--surface);border-radius:10px;border:1px solid var(--border)}
.legend-btn{display:inline-flex;align-items:center;gap:.4rem;padding:.4rem .9rem;border-radius:100px;font-family:'JetBrains Mono',monospace;font-size:.68rem;letter-spacing:.05em;text-transform:uppercase;font-weight:600;cursor:pointer;border:1.5px solid transparent;transition:all .25s ease;user-select:none;background:none}
.legend-btn::before{content:'';width:7px;height:7px;border-radius:50%;flex-shrink:0}
.legend-btn:hover{filter:brightness(1.2)}
.legend-btn[data-s="obsolete"]{background:rgba(255,68,68,.12);color:var(--obsolete)}.legend-btn[data-s="obsolete"]::before{background:var(--obsolete)}
.legend-btn[data-s="legacy"]{background:rgba(255,152,0,.12);color:var(--legacy)}.legend-btn[data-s="legacy"]::before{background:var(--legacy)}
.legend-btn[data-s="current"]{background:rgba(76,175,80,.12);color:var(--current)}.legend-btn[data-s="current"]::before{background:var(--current)}
.legend-btn[data-s="cutting"]{background:rgba(0,188,212,.12);color:var(--cutting)}.legend-btn[data-s="cutting"]::before{background:var(--cutting)}
.legend-btn[data-s="future"]{background:rgba(156,39,176,.12);color:var(--future)}.legend-btn[data-s="future"]::before{background:var(--future)}
.legend-btn[data-s="lossless"]{background:rgba(100,181,246,.12);color:var(--lossless)}.legend-btn[data-s="lossless"]::before{background:var(--lossless)}
.legend-btn.off{opacity:.28;border-color:rgba(255,255,255,.06);filter:saturate(.15)}
.legend-hint{font-family:'JetBrains Mono',monospace;font-size:.58rem;color:var(--text-dim);opacity:.45;align-self:center;margin-left:.5rem}
.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(340px,1fr));gap:1.25rem}
.codec-card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:1.5rem;transition:all .35s ease;position:relative;overflow:hidden}
.codec-card:hover{border-color:var(--accent);transform:translateY(-2px);box-shadow:0 8px 32px rgba(255,107,53,.08)}
.codec-card::after{content:'';position:absolute;top:0;left:0;right:0;height:3px}
.codec-card[data-s="obsolete"]::after{background:var(--obsolete)}.codec-card[data-s="legacy"]::after{background:var(--legacy)}.codec-card[data-s="current"]::after{background:var(--current)}.codec-card[data-s="cutting"]::after{background:var(--cutting)}.codec-card[data-s="future"]::after{background:var(--future)}.codec-card[data-s="lossless"]::after{background:var(--lossless)}
.codec-card.hidden-card{display:none}
.card-top{display:flex;justify-content:space-between;align-items:flex-start;margin-bottom:.75rem;flex-wrap:wrap;gap:.4rem}
.card-name{font-family:'JetBrains Mono',monospace;font-weight:700;font-size:1.15rem}
.card-aka{font-size:.8rem;color:var(--text-dim);margin-bottom:.75rem}
.card-desc{font-size:.88rem;color:var(--text-dim);line-height:1.7;margin-bottom:1rem}
.card-stats{display:grid;grid-template-columns:1fr 1fr;gap:.5rem}
.stat{padding:.5rem .75rem;background:var(--surface2);border-radius:8px}
.stat-label{font-family:'JetBrains Mono',monospace;font-size:.6rem;letter-spacing:.1em;text-transform:uppercase;color:var(--text-dim);margin-bottom:.15rem}
.stat-value{font-weight:600;font-size:.85rem}
.compat-bar{height:6px;background:var(--surface2);border-radius:3px;overflow:hidden;margin-top:.4rem}
.compat-fill{height:100%;border-radius:3px;transition:width 1s ease}.compat-fill.high{background:var(--current)}.compat-fill.med{background:var(--legacy)}.compat-fill.low{background:var(--obsolete)}
.use-case-grid{display:grid;gap:1.5rem}
.use-case{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:2rem;transition:all .3s ease}.use-case:hover{border-color:var(--accent2)}
.uc-header{display:flex;align-items:center;gap:1rem;margin-bottom:1.25rem}
.uc-icon{width:48px;height:48px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:1.5rem;flex-shrink:0}
.uc-title{font-family:'Instrument Serif',serif;font-size:1.5rem}.uc-subtitle{font-size:.8rem;color:var(--text-dim)}
.rec-row{display:grid;grid-template-columns:1fr 1fr 1fr;gap:.75rem;margin-top:1rem}
.rec-row-4{display:grid;grid-template-columns:1fr 1fr 1fr 1fr;gap:.75rem;margin-top:1rem}
@media(max-width:900px){.rec-row{grid-template-columns:1fr}.rec-row-4{grid-template-columns:1fr 1fr}}
@media(max-width:640px){.rec-row-4{grid-template-columns:1fr}}
.rec-box{padding:1rem;background:var(--surface2);border-radius:10px;border-left:3px solid var(--accent2)}.rec-box.audio{border-left-color:var(--accent3)}.rec-box.tip{border-left-color:var(--accent)}
.rec-label{font-family:'JetBrains Mono',monospace;font-size:.6rem;letter-spacing:.12em;text-transform:uppercase;color:var(--text-dim);margin-bottom:.3rem}
.rec-codec{font-family:'JetBrains Mono',monospace;font-weight:700;font-size:1rem;color:var(--accent2)}.rec-codec.audio-val{color:var(--accent3)}.rec-codec.tip-val{color:var(--accent)}
.rec-note{font-size:.78rem;color:var(--text-dim);margin-top:.25rem;line-height:1.6}
.callout{margin-top:1.25rem;padding:1.25rem;background:rgba(255,107,53,.06);border:1px solid rgba(255,107,53,.15);border-radius:10px}
.callout-title{font-family:'JetBrains Mono',monospace;font-size:.7rem;letter-spacing:.1em;text-transform:uppercase;color:var(--accent);margin-bottom:.5rem}
.callout p{font-size:.85rem;color:var(--text-dim);line-height:1.7;margin-bottom:.5rem}.callout p:last-child{margin-bottom:0}
.callout code{font-family:'JetBrains Mono',monospace;font-size:.78rem;background:rgba(255,255,255,.06);padding:.1em .4em;border-radius:4px;color:var(--accent2)}
.callout ul{margin:.5rem 0 .5rem 1.25rem;font-size:.85rem;color:var(--text-dim);line-height:1.8}.callout li{margin-bottom:.35rem}
.callout strong{color:var(--text);font-weight:600}
.slider-wrap{margin-bottom:2rem;padding:1.25rem;background:var(--surface);border:1px solid var(--border);border-radius:10px}
.slider-label{font-family:'JetBrains Mono',monospace;font-size:.7rem;letter-spacing:.08em;text-transform:uppercase;color:var(--text-dim);margin-bottom:.6rem;display:flex;justify-content:space-between;align-items:center}
.slider-val{color:var(--accent);font-weight:700;font-size:.85rem}
.compat-slider{-webkit-appearance:none;appearance:none;width:100%;height:6px;background:var(--surface2);border-radius:3px;outline:none;cursor:pointer}
.compat-slider::-webkit-slider-thumb{-webkit-appearance:none;appearance:none;width:20px;height:20px;border-radius:50%;background:var(--accent);cursor:pointer;border:2px solid var(--bg);box-shadow:0 2px 8px rgba(255,107,53,.3)}
.compat-slider::-moz-range-thumb{width:20px;height:20px;border-radius:50%;background:var(--accent);cursor:pointer;border:2px solid var(--bg);box-shadow:0 2px 8px rgba(255,107,53,.3)}
.compat-card-wrap{transition:opacity .3s ease}
.compat-card-wrap.compat-hidden{display:none}
.toggle-all-btn{padding:.4rem .9rem;border-radius:100px;font-family:'JetBrains Mono',monospace;font-size:.65rem;letter-spacing:.05em;text-transform:uppercase;font-weight:600;cursor:pointer;border:1.5px solid var(--border);background:var(--surface2);color:var(--text-dim);transition:all .25s ease;margin-left:auto}
.toggle-all-btn:hover{border-color:var(--accent);color:var(--text)}
.timeline{position:relative;padding-left:3rem}
.timeline::before{content:'';position:absolute;left:12px;top:0;bottom:0;width:2px;background:linear-gradient(to bottom,var(--accent),var(--accent3),var(--accent2),var(--future))}
.tl-era{margin-bottom:3rem;position:relative}
.tl-era-label{font-family:'JetBrains Mono',monospace;font-size:.7rem;letter-spacing:.15em;text-transform:uppercase;color:var(--accent);margin-bottom:1rem;padding:.3rem .8rem;background:rgba(255,107,53,.1);border-radius:4px;display:inline-block}
.tl-item{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:1.25rem 1.5rem;margin-bottom:1rem;position:relative;transition:all .3s ease;cursor:pointer}
.tl-item:hover{border-color:var(--accent);transform:translateX(4px)}
.tl-item::before{content:'';position:absolute;left:-2.55rem;top:1.5rem;width:10px;height:10px;border-radius:50%;background:var(--accent);border:2px solid var(--bg)}
.tl-header{display:flex;align-items:center;flex-wrap:wrap;gap:.5rem;margin-bottom:.5rem}
.tl-name{font-family:'JetBrains Mono',monospace;font-weight:700;font-size:1rem}
.tl-year{font-family:'JetBrains Mono',monospace;font-size:.75rem;color:var(--text-dim)}
.tl-body{font-size:.9rem;color:var(--text-dim);line-height:1.7;display:none}
.tl-item.expanded .tl-body{display:block;margin-top:.75rem}
.tl-item .expand-hint{font-family:'JetBrains Mono',monospace;font-size:.65rem;color:var(--text-dim);opacity:.5;margin-top:.3rem}
.tl-item.expanded .expand-hint{display:none}
.type-tag{font-family:'JetBrains Mono',monospace;font-size:.6rem;letter-spacing:.08em;text-transform:uppercase;padding:.15rem .5rem;border-radius:4px;background:rgba(108,99,255,.15);color:var(--accent3)}
.type-tag.audio-tag{background:rgba(255,64,129,.15);color:var(--accent4)}
.filter-bar{display:flex;flex-wrap:wrap;gap:.5rem;margin-bottom:2rem}
.filter-pill{padding:.4rem 1rem;border-radius:100px;font-family:'JetBrains Mono',monospace;font-size:.7rem;letter-spacing:.05em;cursor:pointer;border:1px solid var(--border);background:transparent;color:var(--text-dim);transition:all .2s ease}
.filter-pill:hover{border-color:var(--text-dim);color:var(--text)}.filter-pill.active{background:var(--accent);border-color:var(--accent);color:#000}
.subsection-title{font-family:'Instrument Serif',serif;font-size:1.5rem;margin:0 0 1.25rem}
.footnote{font-size:.8rem;color:var(--text-dim);margin-top:3rem;padding-top:2rem;border-top:1px solid var(--border);font-style:italic}
@media(max-width:768px){.card-grid{grid-template-columns:1fr}.card-stats{grid-template-columns:1fr}.hero h1{font-size:2.2rem}.section{padding:2rem 1rem}}