:root{
  --bg:#f2f4f3; --panel:#ffffff; --ink:#11212d; --muted:#53636e; --line:#d5dcdc;
  --accent:#0b6e6e; --accent-ink:#ffffff; --free-bg:#fff1cc; --free-ink:#7a4b00; --danger:#b3261e;
  --ok-bg:#dff3ea; --err-bg:#fde3e1;
}
@media (prefers-color-scheme:dark){
  :root{--bg:#0f1a21; --panel:#16252e; --ink:#e8eef0; --muted:#9fb0b8; --line:#2a3d48;
    --accent:#4cc3bd; --accent-ink:#06201f; --free-bg:#3a2e0d; --free-ink:#f3cf7a; --danger:#ff8a80;
    --ok-bg:#12372c; --err-bg:#43201d;}
}
*{box-sizing:border-box}
html{font-size:17px}
body{margin:0;background:var(--bg);color:var(--ink);font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;line-height:1.6}
a{color:var(--accent)}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:3px solid var(--accent);outline-offset:2px}
h1,h2{line-height:1.2;letter-spacing:-.02em}
h1{font-size:2rem;margin:.4em 0 .3em}
h2{font-size:1.25rem;margin:2em 0 .6em}
.top{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap;padding:.9rem clamp(1rem,4vw,3rem);border-bottom:1px solid var(--line);background:var(--panel)}
.brand{font-weight:800;font-size:1.15rem;letter-spacing:-.02em;color:var(--ink);text-decoration:none}
.top nav{display:flex;align-items:center;gap:1.1rem;flex-wrap:wrap}
.top nav a{color:var(--ink);text-decoration:none}
.top nav a:hover{color:var(--accent)}
.wrap{max-width:62rem;margin:0 auto;padding:1.5rem clamp(1rem,4vw,2rem) 4rem}
.foot{padding:2rem;text-align:center;color:var(--muted);font-size:.85rem}
.lead{color:var(--muted);max-width:42rem}
.crumb{margin:0}
.subnav{display:flex;gap:1.2rem;padding-bottom:.6rem;border-bottom:1px solid var(--line);margin-bottom:1rem}
.btn{display:inline-block;background:var(--accent);color:var(--accent-ink)!important;border:0;border-radius:6px;padding:.6rem 1.1rem;font:inherit;font-weight:600;text-decoration:none;cursor:pointer}
.btn.small{padding:.3rem .8rem;font-size:.9rem}
.btn.ghost{background:transparent;color:var(--accent)!important;box-shadow:inset 0 0 0 2px var(--accent)}
button.link{background:none;border:0;padding:0;font:inherit;color:var(--accent);cursor:pointer;text-decoration:underline}
button.link.danger{color:var(--danger)}
form.inline{display:inline;margin:0}
.flash{padding:.7rem 1rem;border-radius:6px;background:var(--ok-bg);margin:1rem 0}
.flash.err{background:var(--err-bg)}
.empty{color:var(--muted);padding:2rem 0}

.rows{list-style:none;margin:1.5rem 0;padding:0;border-top:1px solid var(--line)}
.rows li{display:flex;justify-content:space-between;gap:1.5rem;align-items:flex-start;padding:1.1rem 0;border-bottom:1px solid var(--line)}
.rows .title{font-size:1.2rem;font-weight:700;color:var(--ink);text-decoration:none}
.rows .title:hover{color:var(--accent);text-decoration:underline}
.rows p{margin:.25rem 0;color:var(--muted)}
.rows small{color:var(--muted)}
.price{white-space:nowrap;font-weight:700;font-variant-numeric:tabular-nums}
.price.free{background:var(--free-bg);color:var(--free-ink);padding:.15rem .6rem;border-radius:99px;font-size:.9rem}

.buy{border-left:4px solid var(--accent);background:var(--panel);padding:.8rem 1.2rem;margin:1.5rem 0}
.buy strong{font-size:1.4rem}
.lessons{margin:0;padding-left:1.4rem}
.lessons li{padding:.35rem 0}
.lessons li.current>a{font-weight:700;color:var(--ink)}
.locked{color:var(--muted)}
.tag{font-size:.78rem;font-style:normal;background:var(--free-bg);color:var(--free-ink);padding:.05rem .5rem;border-radius:99px;margin-left:.4rem}
.tag.lock{background:var(--line);color:var(--muted)}
.files{padding-left:1.2rem}
.files small{color:var(--muted);margin-left:.4rem}

.player-layout{display:grid;grid-template-columns:minmax(0,1fr) 18rem;gap:2.5rem;align-items:start}
.video{position:relative;aspect-ratio:16/9;background:#000;border-radius:8px;overflow:hidden;margin-bottom:1rem}
.video iframe{position:absolute;inset:0;width:100%;height:100%;border:0}
@media (max-width:52rem){.player-layout{grid-template-columns:1fr}}

.form{display:grid;gap:1rem;max-width:36rem}
.form.narrow{max-width:24rem}
.form label{display:grid;gap:.3rem;font-weight:600}
.form label.check{display:flex;gap:.5rem;align-items:center;font-weight:400}
input,select,textarea{font:inherit;color:var(--ink);background:var(--panel);border:1px solid var(--line);border-radius:6px;padding:.55rem .7rem;width:100%}
input[type=checkbox]{width:auto}
.note{color:var(--muted);font-size:.9rem}

.stats{display:flex;flex-wrap:wrap;gap:2rem;margin:1.5rem 0}
.stats div{min-width:6rem}.stats dt{color:var(--muted);font-size:.9rem}.stats dd{margin:0;font-size:2rem;font-weight:800;font-variant-numeric:tabular-nums}
.table{width:100%;border-collapse:collapse;font-size:.95rem;display:block;overflow-x:auto}
.table th,.table td{text-align:left;padding:.55rem .8rem .55rem 0;border-bottom:1px solid var(--line);vertical-align:middle}
.table th{color:var(--muted);font-weight:600}
.actions{display:flex;gap:1rem;align-items:center}
.actions form{margin:0}
@media (prefers-reduced-motion:no-preference){a,.btn{transition:color .15s,background-color .15s}}