/* Minimal clean UI for AI C Learner */
:root{
  --bg:#f6f8fa;--card:#fff;--accent:#2b7cff;--muted:#6b7280;--maxw:980px;
}
*{box-sizing:border-box}
body{font-family:Inter, ui-sans-serif, system-ui, -apple-system, 'Helvetica Neue', Arial; background:var(--bg); color:#111; margin:0}
.container{max-width:var(--maxw);margin:24px auto;padding:0 16px}
.site-header{background:linear-gradient(90deg,#fff 0,#f8fbff 100%);border-bottom:1px solid #e6eef8}
.site-header .container{display:flex;align-items:center;justify-content:space-between;padding:12px 16px}
.brand a{font-weight:700;color:var(--accent);text-decoration:none;font-size:20px}
.main-nav a{margin-left:14px;color:#334155;text-decoration:none}
.nav-toggle{display:none;background:none;border:0;font-size:20px}
main.container{padding-top:28px}
.card{background:var(--card);border-radius:10px;padding:18px;box-shadow:0 6px 18px rgba(22,33,62,0.06);margin-bottom:16px}
h1{margin-top:0}
.form-row{margin-bottom:12px}
input[type=text],input[type=password],textarea{width:100%;padding:10px;border-radius:8px;border:1px solid #dbe7ff;background:#fff}
button{background:var(--accent);color:#fff;padding:10px 14px;border-radius:8px;border:0;cursor:pointer}
button.secondary{background:#f3f4f6;color:#111}
pre{background:#0f1724;color:#e6f0ff;padding:12px;border-radius:8px;overflow:auto}
.site-footer{padding:16px 0;color:var(--muted);text-align:center;margin-top:24px}
@media(max-width:700px){
  .main-nav{display:none}
  .nav-toggle{display:block}
}