:root {
  --bg:#0b1e33; --panel:#0f2a47; --card:#123356; --muted:#a8bdcf;
  --accent:#1ea7fd; --grid:#1a3d66; --event:#3c78d8; --danger:#ff5a5a;
  --ok:#3fb950; --text:#e8f3ff;
  --hour-h:60px; --col-w:1fr;
  --radius:16px;
  --shadow:0 8px 24px rgba(0,0,0,.25);
  font-family: Heebo, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
}
* { box-sizing:border-box }
html,body { height:100%; background:var(--bg); color:var(--text); margin:0 }
a { color:var(--accent); text-decoration:none }
a:hover { text-decoration:underline }
.hidden { display:none !important }

.topbar {
  display:flex; align-items:center; justify-content:space-between;
  padding:12px 16px; background:#071727; border-bottom:1px solid #102742;
  position:sticky; top:0; z-index:10;
}
.topbar .brand { font-weight:800; letter-spacing:.5px }
.topbar .actions a { margin-inline:8px; white-space:nowrap }

.layout {
  display:grid; grid-template-columns:280px 1fr; gap:16px;
  padding:16px; height:calc(100% - 56px);
}
.sidebar {
  background:var(--panel); border:1px solid #143257; border-radius:var(--radius);
  padding:12px; overflow:auto; box-shadow:var(--shadow);
}
.course-item {
  background:var(--card); border:1px solid #1d4674; border-radius:12px;
  padding:10px 12px; margin-bottom:10px; cursor:pointer; user-select:none; line-height:1.3;
}
.course-item small { color:var(--muted) }
.course-item.active { outline:2px solid var(--ok) }
.course-item .del { color:#ffd166; margin-inline-start:6px }

.calendar {
  display:grid;
  grid-template-rows:40px repeat(12, var(--hour-h));
  position:relative;
  background:var(--panel);
  border:1px solid #143257;
  border-radius:var(--radius);
  min-width:980px;
  box-shadow:var(--shadow);
}

.day-layer {
  position:absolute !important;
  top:40px; left:0;
  width:100%;
  height:calc(var(--hour-h) * 12);
  pointer-events:none;
}
.day-layer .event {
  pointer-events:auto;
  position:absolute;
}

.calendar .head { display:contents }
.calendar .dayhead {
  display:flex; align-items:center; justify-content:center;
  border-left:1px solid #143257; background:#0c2745; font-weight:600;
}
.calendar .timecell {
  display:flex; align-items:center; justify-content:center;
  border-top:1px solid #123154; color:var(--muted); font-size:12px; background:#0a2340;
}
.calendar .cell {
  position:relative; border-left:1px solid #143257; border-top:1px solid #113257;
}
.calendar .event {
  position:absolute; left:6px; right:6px;
  border-radius:10px; padding:6px 8px;
  background:var(--event); color:#fff; box-shadow:0 4px 14px rgba(0,0,0,.3);
  font-size:12px; line-height:1.2; overflow:hidden;
}
.event .link { display:block; color:#fff; text-decoration:underline }
.event .meta { opacity:.9 }

.event .remove {
  position:absolute;
  top:6px; inset-inline-end:8px;
  width:22px; height:22px; line-height:22px; text-align:center;
  background:rgba(255,255,255,0.15);
  border:none; border-radius:50%;
  color:#fff; cursor:pointer; font-weight:800; font-size:14px;
  padding:0; display:flex; align-items:center; justify-content:center;
  z-index:5;
  box-shadow:0 1px 3px rgba(0,0,0,0.3);
  transition:background 0.15s ease, transform 0.15s ease;
}
.event .remove:hover { background:rgba(255,255,255,0.3); transform:scale(1.1); }

.alert {
  color:#fff; background:var(--danger);
  border-radius:8px; padding:8px; margin:8px 0;
}

/* Off-grid bar */
.offgrid {
  grid-column:1 / -1;
  display:flex; flex-wrap:wrap; align-items:flex-start;
  gap:14px; padding:16px 18px; margin-bottom:20px;
  background:var(--panel); border:1px solid #143257; border-radius:20px;
  box-shadow:var(--shadow); transition:all 0.25s ease-in-out;
}

.offgrid .event-card {
  background:var(--event);
  color:#fff; border-radius:14px;
  padding:10px 14px 12px;
  width:300px;
  box-shadow:0 4px 14px rgba(0,0,0,0.3);
  position:relative;
  display:flex; flex-direction:column; justify-content:space-between;
  line-height:1.3; font-size:13px;
  transition:transform 0.2s ease, box-shadow 0.2s ease;
  overflow:visible;
}
.offgrid .event-card:hover {
  transform:translateY(-2px);
  box-shadow:0 6px 18px rgba(0,0,0,0.4);
}

.offgrid .event-card .remove {
  position:absolute;
  top:6px; inset-inline-end:8px;
  width:22px; height:22px; line-height:22px;
  text-align:center; background:rgba(255,255,255,0.08);
  border:none; border-radius:50%;
  color:#fff; cursor:pointer; font-weight:800; font-size:14px;
  padding:0; display:flex; align-items:center; justify-content:center;
  transition:background 0.15s ease;
  z-index:5; pointer-events:auto;
}
.offgrid .event-card .remove:hover { background:rgba(255,255,255,0.2); }

.offgrid .event-card .meta { opacity:0.95; font-size:12.5px; }
.offgrid .event-card .link {
  color:#fff; text-decoration:underline; margin-top:4px; display:inline-block;
}
.offgrid .event-card .meta-line { margin-top:2px; }

/* Chip style */
.chip {
  flex:0 0 auto;
  display:inline-flex; align-items:center;
  background:#2a4e7d; color:#eaf3ff;
  border-radius:999px; padding:8px 14px;
  font-size:13px; font-weight:500;
  box-shadow:0 2px 6px rgba(0,0,0,0.2);
  white-space:nowrap; line-height:1.4;
  transition:background 0.2s ease;
}
.chip:hover { background:#3a6bab; }
.chip button {
  margin-inline-start:10px; background:transparent; border:none; color:#fff;
  font-weight:800; cursor:pointer; font-size:14px; line-height:1;
  transition:opacity 0.2s ease;
}
.chip button:hover { opacity:0.6; }
.chip .x { margin-inline-start:8px; background:transparent; border:none; color:#fff; cursor:pointer; font-weight:800; }