:root{
  /* Default = dark; body.light switches to light */
  --bg:#0b1220; --card:#0f172a; --text:#e5e7eb; --muted:#9aa3b2;
  --accent:#22d3ee; --accent-2:#34d399; --progress-bg:#1f2937;
  --border:#1f2a3a; --link:#38bdf8; --shadow:0 10px 30px rgba(34,211,238,.15);
}
body.light{
  --bg:#f8fafc; --card:#ffffff; --text:#0f172a; --muted:#475569;
  --accent:#06b6d4; --accent-2:#22c55e; --progress-bg:#e2e8f0;
  --border:#e5e7eb; --link:#0ea5e9; --shadow:0 10px 30px rgba(34,197,94,.15);
}

*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,Apple Color Emoji,Segoe UI Emoji;background:var(--bg);color:var(--text);line-height:1.6;}
a{color:var(--link);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:1100px;margin:0 auto;padding:16px}

/* Header */
.site-header{position:sticky;top:0;z-index:20;background:rgba(11,18,32,.7);backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}
.nav{display:flex;gap:14px;align-items:center;justify-content:space-between;flex-wrap:wrap}
.brand{font-weight:800;font-size:18px;color:inherit;text-decoration:none;white-space:nowrap}
.nav-links a{margin:0 8px;color:var(--muted)}
.btn{padding:10px 14px;border-radius:10px;font-weight:700}
.btn.primary{background:linear-gradient(135deg,var(--accent),var(--accent-2));color:#fff;box-shadow:var(--shadow)}

.hero{padding:56px 16px 32px}
.grid{display:grid;grid-template-columns:1.2fr .8fr;gap:32px}
.card{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:18px}
.h1{font-size:clamp(28px,4vw,40px);margin:0 0 10px}
.lead{color:var(--muted);font-size:18px}
.cta{display:flex;gap:12px;margin-top:18px;flex-wrap:wrap}
.badges{display:flex;gap:10px;margin-top:10px;flex-wrap:wrap}
.badge{border:1px solid var(--border);padding:6px 10px;border-radius:999px;background:#0d1526}
.list{padding-left:18px}
.section{padding:12px 16px 40px}
.footer{color:var(--muted);font-size:13px;border-top:1px solid var(--border);padding:24px 0;margin-top:24px}
.footer a{color:var(--muted)}

/* Course-specific */
.sub{color:var(--muted);margin:0 0 12px}
.toolbar{display:flex;flex-direction:column;gap:12px;margin:8px 0 14px}
.control-row{display:flex;gap:12px;align-items:center}
.week-row{display:grid;grid-template-columns:140px 1fr 140px;align-items:center;gap:12px}
.week-title{text-align:center;font-size:15px;color:var(--muted)}
input[type=text]{padding:10px 12px;border:1px solid var(--border);border-radius:10px;background:var(--card);color:var(--text);min-width:220px;width:100%}
.toggle{cursor:pointer;border:1px solid var(--border);background:var(--card);color:var(--text);padding:10px 12px;border-radius:12px;box-shadow:0 4px 18px rgba(56,189,248,.18)}
.toggle.nowrap{white-space:nowrap}
.btn{cursor:pointer;border:none;padding:12px 16px;border-radius:12px;font-weight:600;background:linear-gradient(135deg,var(--accent),var(--accent-2));color:#fff;box-shadow:var(--shadow);width:100%}
.btn:disabled{opacity:.5;cursor:not-allowed}

.progress{width:100%;height:12px;background:var(--progress-bg);border-radius:999px;overflow:hidden;border:1px solid var(--border)}
.bar{height:100%;width:0%;background:linear-gradient(90deg,var(--accent),var(--accent-2));transition:width .25s ease}
.statusline{display:flex;justify-content:space-between;color:var(--muted);font-size:14px;margin-top:4px}
.day{border-top:1px dashed var(--border);padding-top:12px;margin-top:12px}
.day:first-child{border-top:none;padding-top:0;margin-top:0}
.day h3{margin:0 0 8px;font-size:18px}
.items{display:grid;grid-template-columns:1fr;gap:8px}
.item{display:flex;gap:10px;align-items:flex-start;background:color-mix(in srgb, var(--card) 92%, var(--accent) 8%);padding:10px 12px;border:1px solid var(--border);border-radius:12px}
.item input{margin-top:3px}
.muted{color:var(--muted)}
.badge{display:inline-block;font-size:11px;padding:3px 8px;border-radius:999px;margin-left:8px;border:1px solid var(--border)}
.badge.must{background:color-mix(in srgb, var(--accent) 18%, var(--card) 82%);border-color:color-mix(in srgb, var(--accent) 45%, var(--border) 55%);font-weight:700}
.badge.high{background:color-mix(in srgb, var(--accent-2) 12%, var(--card) 88%);border-color:color-mix(in srgb, var(--accent-2) 40%, var(--border) 60%)}
.badge.nice{background:color-mix(in srgb, #f59e0b 12%, var(--card) 88%);border-color:color-mix(in srgb, #f59e0b 40%, var(--border) 60%)}
.focus{margin:6px 0 12px;color:var(--muted);font-size:14px}
.legend{background:var(--card);border:1px solid var(--border);border-radius:12px;margin:8px 0 12px;padding:10px 12px}
.legend summary{display:flex;align-items:center;gap:8px;cursor:pointer;list-style:none}
.legend summary::-webkit-details-marker{display:none}
.legend-body{margin-top:6px;color:var(--muted);font-size:14px}

/* ---- Slim, pill-like legend (desktop + mobile) ---- */
.legend.legend--compact{
  padding:6px 10px;
  margin:8px 0 10px;
  border-radius:10px;
  background:var(--card);
  border:1px solid var(--border);
}
.legend.legend--compact summary{
  display:flex; align-items:center; gap:8px;
  cursor:pointer; list-style:none;
  font-size:13px; color:var(--muted);
  padding:0; /* no extra height */
}
.legend.legend--compact summary::-webkit-details-marker{ display:none; }
.legend-chip{
  background:color-mix(in srgb, var(--card) 88%, var(--accent) 12%);
  border:1px solid var(--border);
  padding:2px 8px;
  border-radius:999px;
  color:var(--text);
  font-weight:600;
  font-size:12px;
}
.legend-dot{ opacity:.5; }
.legend-hint{ margin-left:auto; font-size:12px; opacity:.7; }

/* Keep body tiny and out of the way; collapsed by default */
.legend.legend--compact .legend-body{
  margin-top:6px;
  color:var(--muted);
  font-size:13px;
}

/* Must-Know toggle labels */
.must-toggle{display:flex;align-items:center;justify-content:center;gap:8px;padding:8px 10px}
.must-toggle input{margin:0}
.must-toggle .label-text{display:inline-flex;align-items:center}
.text-mobile{display:none}
.text-desktop{display:inline}

/* Mobile */
.mobile-only{display:none !important}
@media (max-width:860px){.grid{grid-template-columns:1fr}}
@media (max-width:640px){
  .sub{display:none}
  .toolbar{gap:8px}
  .control-row{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.4fr) minmax(0,1fr);gap:8px}
  .toggle{padding:8px 10px}
  .toggle.nowrap{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

  .week-row{display:none !important}
  .desktop-only{display:none !important}
  .mobile-only{display:block !important}

  .mbar{display:grid;grid-template-columns:1fr;align-items:center;gap:8px;background:var(--card);border:1px solid var(--border);border-radius:12px;padding:6px 8px;margin:6px 0 8px}
  .mbar-title{font-size:13px;font-weight:600;text-align:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:var(--muted)}

  /* Hide legend entirely on phones */
  #legendBox{ 
    padding:4px 8px !important;
    margin:6px 0 8px !important;
  }
  .legend.legend--compact summary{ font-size:12px; gap:6px; }
  .legend-chip{ font-size:11px; padding:2px 6px; }
  .legend-hint{ display:none; }         /* remove “Legend” word on phones */
  .legend.legend--compact .legend-body{ display:none !important; } /* never expands */
}


  .statusline{font-size:12px}
  .bottom-nav{position:sticky;bottom:0;z-index:9;background:var(--bg);border-top:1px solid var(--border);padding:8px 12px;display:flex;gap:10px;backdrop-filter:blur(8px)}
  .bottom-nav .btn{flex:1}

  /* Must-Know label – short on mobile */
  .text-desktop{display:none}
  .text-mobile{display:inline}
}