:root{
  --bg:#0b1020; --bg2:#111836; --card:#151d3b; --card2:#1a2347;
  --line:#263056; --text:#e8ecf8; --muted:#93a0c4;
  --blue:#4f8cff; --blue2:#6ea8ff; --green:#2dd4a7; --amber:#f5a623; --red:#ff5d6c;
  --radius:18px; --shadow:0 12px 40px rgba(0,0,0,.35);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Inter',system-ui,-apple-system,sans-serif;
  background:
    radial-gradient(1000px 500px at 80% -10%, rgba(79,140,255,.22), transparent 60%),
    radial-gradient(800px 400px at 0% 10%, rgba(45,212,167,.12), transparent 55%),
    var(--bg);
  color:var(--text); min-height:100vh; line-height:1.6;
}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}
header{padding:26px 0 10px;display:flex;align-items:center;gap:14px;justify-content:space-between;flex-wrap:wrap}
.logo{display:flex;align-items:center;gap:12px;font-weight:800;font-size:1.25rem}
.logo .badge{
  width:42px;height:42px;border-radius:12px;display:grid;place-items:center;
  background:linear-gradient(135deg,var(--blue),#7c5cff);font-size:22px;box-shadow:0 6px 20px rgba(79,140,255,.4);
}
.logo small{display:block;font-size:.72rem;color:var(--muted);font-weight:500;margin-top:2px}
nav a{color:var(--muted);text-decoration:none;font-size:.9rem;margin-left:18px;transition:.2s}
nav a:hover{color:#fff}

.hero{text-align:center;padding:52px 0 34px}
.hero .kicker{
  display:inline-block;background:rgba(79,140,255,.12);border:1px solid rgba(79,140,255,.35);
  color:var(--blue2);font-size:.8rem;font-weight:600;padding:6px 14px;border-radius:999px;letter-spacing:.3px;margin-bottom:18px;
}
.hero h1{font-size:clamp(1.9rem,5vw,3.2rem);font-weight:800;letter-spacing:-1px;line-height:1.15;margin-bottom:14px}
.hero h1 span{background:linear-gradient(90deg,var(--blue2),#7c5cff);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.hero p{color:var(--muted);max-width:640px;margin:0 auto;font-size:1.02rem}

.tabs{display:flex;justify-content:center;gap:10px;margin:30px auto 22px;background:var(--card);border:1px solid var(--line);padding:6px;border-radius:14px;width:fit-content}
.tab{
  border:0;background:transparent;color:var(--muted);font:inherit;font-weight:600;font-size:.92rem;
  padding:10px 26px;border-radius:10px;cursor:pointer;transition:.2s;display:flex;align-items:center;gap:8px;
}
.tab.active{background:linear-gradient(135deg,var(--blue),#7c5cff);color:#fff;box-shadow:0 6px 18px rgba(79,140,255,.35)}
.tab:hover:not(.active){color:#fff}

.dropzone{
  border:2px dashed var(--line);border-radius:var(--radius);background:var(--card);
  padding:70px 30px;text-align:center;cursor:pointer;transition:.25s;position:relative;overflow:hidden;
}
.dropzone:hover,.dropzone.over{border-color:var(--blue);background:var(--card2);transform:translateY(-2px);box-shadow:var(--shadow)}
.dz-icon{font-size:52px;margin-bottom:14px;filter:drop-shadow(0 6px 16px rgba(79,140,255,.35))}
.dropzone h3{font-size:1.15rem;margin-bottom:6px}
.dropzone p{color:var(--muted);font-size:.9rem}
.dropzone .formats{display:inline-block;margin-top:14px;font-size:.75rem;background:rgba(255,255,255,.05);border:1px solid var(--line);padding:5px 14px;border-radius:999px;color:var(--muted)}
.dropzone input[type=file]{position:absolute;inset:0;opacity:0;cursor:pointer}

.preview-card{display:none;margin-top:20px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:18px;align-items:center;gap:16px;flex-wrap:wrap}
.preview-card.show{display:flex}
.preview-card img,.preview-card video{max-width:150px;max-height:110px;border-radius:10px;object-fit:cover;background:#000}
.preview-info{flex:1;min-width:200px}
.preview-info b{display:block;margin-bottom:2px;word-break:break-all}
.preview-info span{color:var(--muted);font-size:.85rem}
.preview-info .progress{height:6px;background:rgba(255,255,255,.08);border-radius:99px;margin-top:12px;overflow:hidden}
.preview-info .progress i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--blue),#7c5cff);border-radius:99px;transition:width .3s}
.preview-info .progtext{font-size:.75rem;color:var(--muted);margin-top:6px}

.result{margin-top:26px}
.verdict-card{
  border-radius:var(--radius);padding:26px;background:var(--card);border:1px solid var(--line);
  display:flex;gap:22px;align-items:center;flex-wrap:wrap;margin-bottom:22px;
}
.verdict-badge{width:86px;height:86px;border-radius:50%;display:grid;place-items:center;flex-shrink:0}
.verdict-badge svg{width:44px;height:44px}
.verdict-badge.human{background:rgba(45,212,167,.14);border:3px solid var(--green);color:var(--green)}
.verdict-badge.ai{background:rgba(255,93,108,.14);border:3px solid var(--red);color:var(--red)}
.verdict-badge.mix{background:rgba(245,166,35,.14);border:3px solid var(--amber);color:var(--amber)}
.verdict-body{flex:1;min-width:240px}
.verdict-body h2{font-size:1.4rem;margin-bottom:4px}
.verdict-body p{color:var(--muted);font-size:.9rem}

.meter{display:flex;flex-direction:column;align-items:center;flex-shrink:0}
.meter .ring{position:relative;width:100px;height:100px;border-radius:50%;background:conic-gradient(var(--blue) calc(var(--p)*1%),rgba(255,255,255,.08) 0);display:grid;place-items:center}
.meter .ring::before{content:'';position:absolute;inset:9px;background:var(--card);border-radius:50%}
.meter .ring b{position:relative;font-size:1.4rem;font-weight:800}
.meter label{font-size:.72rem;color:var(--muted);margin-top:6px}

.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:14px;margin-bottom:22px}
.gauge{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px}
.gauge .top{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px}
.gauge .top b{font-size:.88rem;font-weight:600}
.gauge .top em{font-style:normal;font-size:.8rem;font-weight:700}
.gauge .bar{height:7px;background:rgba(255,255,255,.07);border-radius:99px;overflow:hidden}
.gauge .bar i{display:block;height:100%;border-radius:99px;transition:width .8s ease}
.gauge small{display:block;margin-top:8px;color:var(--muted);font-size:.72rem}

.panel{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;margin-bottom:18px}
.panel h3{font-size:.95rem;font-weight:700;margin-bottom:14px;display:flex;align-items:center;gap:8px;color:var(--blue2)}
.panel h3 .n{width:22px;height:22px;border-radius:7px;background:rgba(79,140,255,.15);display:grid;place-items:center;font-size:.75rem}
table{width:100%;border-collapse:collapse;font-size:.85rem}
th,td{text-align:left;padding:8px 10px;border-bottom:1px solid rgba(255,255,255,.05);vertical-align:top;word-break:break-word}
th{color:var(--muted);font-weight:600;width:38%}
tr:last-child td,tr:last-child th{border-bottom:0}
.chip{display:inline-block;background:rgba(79,140,255,.12);border:1px solid rgba(79,140,255,.3);color:var(--blue2);font-size:.72rem;padding:3px 10px;border-radius:99px;margin:3px 3px 0 0}
.chip.red{background:rgba(255,93,108,.12);border-color:rgba(255,93,108,.35);color:var(--red)}
.chip.green{background:rgba(45,212,167,.12);border-color:rgba(45,212,167,.35);color:var(--green)}
.chip.amber{background:rgba(245,166,35,.12);border-color:rgba(245,166,35,.35);color:var(--amber)}
.alert{border-radius:12px;padding:12px 15px;font-size:.85rem;margin-bottom:16px;border:1px solid}
.alert.info{background:rgba(79,140,255,.08);border-color:rgba(79,140,255,.3);color:var(--blue2)}
.alert.warn{background:rgba(245,166,35,.08);border-color:rgba(245,166,35,.35);color:var(--amber)}
.err{border-radius:12px;padding:14px 16px;font-size:.9rem;margin-top:18px;background:rgba(255,93,108,.1);border:1px solid rgba(255,93,108,.35);color:var(--red)}
.buttons{display:flex;gap:10px;margin-top:16px;flex-wrap:wrap}
.btn{
  border:0;cursor:pointer;font:inherit;font-weight:700;font-size:.9rem;padding:12px 22px;border-radius:12px;transition:.2s;
}
.btn.primary{background:linear-gradient(135deg,var(--blue),#7c5cff);color:#fff;box-shadow:0 6px 18px rgba(79,140,255,.3)}
.btn.primary:hover{transform:translateY(-2px);box-shadow:0 10px 24px rgba(79,140,255,.45)}
.btn.ghost{background:transparent;border:1px solid var(--line);color:var(--text)}
.btn.ghost:hover{border-color:var(--blue2);color:var(--blue2)}

.rules{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px;margin:40px 0}
.rule{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:18px}
.rule .ico{font-size:26px;margin-bottom:8px}
.rule b{font-size:.92rem;display:block;margin-bottom:4px}
.rule p{font-size:.8rem;color:var(--muted)}

footer{border-top:1px solid var(--line);padding:26px 0 40px;margin-top:30px;text-align:center;color:var(--muted);font-size:.8rem}
footer a{color:var(--blue2);text-decoration:none}
.spin{display:inline-block;animation:sp 1s linear infinite}
@keyframes sp{to{transform:rotate(360deg)}}
@media(max-width:640px){
  .hero{padding:36px 0 26px}
  .tabs{width:100%}
  .tab{flex:1;padding:10px 8px;justify-content:center}
  .dropzone{padding:50px 18px}
  .verdict-card{gap:14px}
}