/* Shared styles for /lessons/<slug>/ landing pages and the /lessons/ hub. Static, server-rendered content: no JS is required to read these pages. */
:root{color-scheme:light;--paper:#f3efe6;--paper2:#fffdf7;--ink:#17212b;--navy:#16344c;--navy2:#0f2b41;--blue:#2463eb;--yellow:#f3c84b;--line:#d8d0c2;--muted:#56626d;--green:#1c7a53;--greenbg:#e3f4ec}
*{box-sizing:border-box}
body{margin:0;background:var(--paper);color:var(--ink);font:15px/1.6 Inter,system-ui,-apple-system,"Segoe UI",Arial,sans-serif}
a{color:var(--blue)}
a:focus-visible,button:focus-visible{outline:3px solid var(--blue);outline-offset:2px}
.top{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;padding:12px 22px;background:var(--navy);color:#fff}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none}
.logo{width:38px;height:38px;border-radius:9px;background:var(--navy2);box-shadow:3px 3px 0 var(--yellow);display:grid;place-items:center;font:900 13px Inter,system-ui}
.brand b{display:block;font-size:14px}.brand small{display:block;font-size:11px;color:#c3d6e6}
.nav a{color:#fff;text-decoration:none;font-size:13px;font-weight:700;border:1px solid #4d7391;border-radius:8px;padding:7px 11px;margin-left:8px}
.wrap{max-width:900px;margin:0 auto;padding:26px 18px 56px}
.kicker{font:700 11px "JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.kicker a{color:var(--muted);text-decoration:underline}
h1{font:800 clamp(28px,4.4vw,44px)/1.1 Inter,system-ui;margin:8px 0 10px;color:var(--navy)}
.lead{max-width:68ch;color:#33414d;font-size:16px}
.unit-chip{display:inline-block;margin:14px 0 2px;padding:4px 12px;border-radius:99px;font-size:12px;font-weight:800;color:#fff}
.buttons{display:flex;gap:10px;flex-wrap:wrap;margin:22px 0 6px}
.btn{display:inline-flex;align-items:center;gap:7px;border:1px solid var(--navy);background:#fff;color:var(--navy);border-radius:9px;padding:11px 15px;font-size:14px;font-weight:800;text-decoration:none;box-shadow:2px 2px 0 #d7cebf}
.btn.primary{background:var(--navy);color:#fff;box-shadow:2px 2px 0 var(--yellow)}
.btn.free{background:var(--greenbg);color:var(--green);border-color:var(--green)}
section.block{margin:30px 0}
section.block h2{font:800 20px Inter,system-ui;color:var(--navy);margin:0 0 8px}
.gallery{display:flex;gap:10px;flex-wrap:wrap;margin:14px 0}
.gallery img{width:160px;height:120px;object-fit:cover;border:1px solid var(--line);border-radius:8px;background:#fff}
table{width:100%;border-collapse:collapse;background:var(--paper2);border:1px solid var(--line);border-radius:10px;overflow:hidden;font-size:14px}
th,td{text-align:left;vertical-align:top;padding:9px 12px;border-bottom:1px solid var(--line)}
th{background:#e9e3d4;font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:#3d4a55}
td.code{font:700 13px "JetBrains Mono",ui-monospace,monospace;white-space:nowrap;width:1%}
.other-lessons{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:8px;margin-top:10px}
.other-lessons a{display:block;border:1px solid var(--line);background:var(--paper2);border-radius:8px;padding:9px 11px;text-decoration:none;color:var(--navy);font-size:13px;font-weight:700}
.other-lessons a:hover{border-color:var(--navy)}
.other-lessons a.current{background:var(--navy);color:#fff;border-color:var(--navy)}
.small{font-size:12px;color:var(--muted);margin-top:30px;max-width:72ch}
.hub-list{list-style:none;margin:0;padding:0;display:grid;gap:10px}
.hub-unit{margin:26px 0 10px;font:800 13px "JetBrains Mono",ui-monospace,monospace;letter-spacing:.08em;text-transform:uppercase;color:var(--navy)}
.hub-card{display:block;border:1px solid var(--line);background:var(--paper2);border-radius:10px;padding:13px 15px;text-decoration:none;color:var(--ink)}
.hub-card b{display:block;color:var(--navy);font-size:15px;margin-bottom:3px}
.hub-card span{font-size:13px;color:var(--muted)}
@media (max-width:640px){.wrap{padding:18px 16px 48px}.gallery img{width:130px;height:98px}}

.skip{position:absolute;left:-9999px;top:8px;z-index:100;background:var(--yellow);color:var(--ink);padding:9px 14px;border-radius:8px;font-weight:800;text-decoration:none}
.skip:focus{left:8px}
.res-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:10px;margin:10px 0}
.res-card{display:block;border:1px solid var(--line);background:var(--paper2);border-radius:10px;padding:12px 14px;text-decoration:none;color:var(--ink)}
.res-card b{display:block;color:var(--navy);font-size:14px;margin-bottom:3px}
.res-card span{display:block;font-size:13px;color:#33414d}
.res-card.free{background:var(--greenbg);border-color:var(--green)}
.res-card:hover{border-color:var(--navy)}
.prevnext{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;margin:26px 0}
.prevnext a{flex:1 1 220px;border:1px solid var(--line);background:var(--paper2);border-radius:10px;padding:11px 14px;text-decoration:none;color:var(--navy);font-weight:800}
.prevnext small{display:block;font:700 11px "JetBrains Mono",ui-monospace,monospace;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
.prevnext .next{text-align:right}
@media(max-width:600px){.top{padding:10px 14px}.nav{display:flex;flex-wrap:wrap;gap:6px}.nav a{margin-left:0}}