/* =====================================================================
   Smart Timetable Generator — LMS-Matched CSS Theme
   LMS Design System: Primary #4f46e5/#7c3aed, Font: Plus Jakarta Sans
   ===================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

:root {
  --bg:     #f8fafc;         /* LMS background */
  --card:   #ffffff;         /* LMS card white */
  --ink:    #0f172a;         /* LMS dark text */
  --muted:  #64748b;         /* LMS muted text */
  --pri:    #7c3aed;         /* LMS primary violet */
  --pri2:   #4f46e5;         /* LMS primary indigo */
  --pri-hover: #6d28d9;      /* LMS hover */
  --pri-light: #f3e8ff;      /* LMS purple tint */
  --pri-border:#ddd6fe;      /* LMS purple border */
  --ok:     #059669;         /* Success green */
  --bad:    #be123c;         /* Danger red */
  --line:   #e2e8f0;         /* LMS border */
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: 'Plus Jakarta Sans', 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.5;
}

/* ── Header ── */
header {
  background: linear-gradient(135deg, var(--pri), var(--pri2));
  color: #fff;
  padding: 20px 32px;
  box-shadow: 0 10px 25px -5px rgba(124, 58, 237, 0.35);
}
header h1 { margin: 0; font-size: 22px; font-weight: 800; letter-spacing: -0.02em; }
header p  { margin: 4px 0 0; opacity: 0.88; font-size: 13px; font-weight: 500; }

/* ── Main Layout ── */
main { max-width: 1100px; margin: 28px auto; padding: 0 20px; }

/* ── Cards — LMS rounded white ── */
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 22px 26px;
  margin-bottom: 20px;
  box-shadow: 0 4px 14px -2px rgba(15, 23, 42, 0.04);
}
.card h2 {
  margin: 0 0 14px;
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
}

/* ── Form Labels ── */
label {
  font-size: 13px;
  color: var(--muted);
  font-weight: 600;
  display: block;
  margin-bottom: 4px;
}

/* ── Inputs — LMS style ── */
input, select, textarea {
  padding: 9px 12px;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  font: inherit;
  background: #fff;
  color: var(--ink);
  transition: border-color 0.2s ease;
  font-size: 13px;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--pri);
}
input[type=text], textarea { width: 100%; }

/* ── Buttons — LMS primary purple ── */
button {
  padding: 10px 18px;
  border: none;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--pri), var(--pri2));
  color: #fff;
  font: inherit;
  font-weight: 700;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 4px 12px rgba(124, 58, 237, 0.25);
}
button:hover { background: linear-gradient(135deg, var(--pri-hover), var(--pri)); transform: translateY(-1px); }
button:active { transform: translateY(0); }

button.sec {
  background: var(--card);
  color: var(--pri);
  border: 1.5px solid var(--pri-border);
  box-shadow: none;
}
button.sec:hover { background: var(--pri-light); }

button.del {
  background: #fff;
  color: var(--bad);
  border: 1px solid #fecdd3;
  padding: 5px 10px;
  border-radius: 8px;
  box-shadow: none;
}
button.del:hover { background: #fff1f2; }

button:disabled { opacity: 0.5; cursor: wait; box-shadow: none; }

/* ── Layout Row ── */
.row { display: flex; gap: 14px; flex-wrap: wrap; align-items: flex-end; }
.row > div { flex: 1; min-width: 140px; }

/* ── Table ── */
table { border-collapse: collapse; width: 100%; font-size: 13px; }
th, td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; }
th {
  background: #f8fafc;
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ── Messages ── */
.msg { padding: 12px 16px; border-radius: 12px; margin: 12px 0; font-size: 13px; font-weight: 600; }
.msg.err { background: #fff1f2; color: var(--bad); border: 1px solid #fecdd3; }
.msg.ok  { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }

/* ── Timetable Result Tabs — LMS purple ── */
.tabs { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 14px; }
.tabs button {
  background: var(--card);
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: none;
  padding: 8px 16px;
  border-radius: 10px;
  font-size: 13px;
}
.tabs button.on {
  background: linear-gradient(135deg, var(--pri), var(--pri2));
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 10px rgba(124, 58, 237, 0.3);
}

/* ── Result Grid ── */
.grid td {
  text-align: center;
  min-width: 110px;
  height: 58px;
  font-size: 13px;
  vertical-align: middle;
}
.grid td small { display: block; color: var(--muted); font-size: 11px; }

/* ── Utility ── */
.muted { color: var(--muted); font-size: 13px; }
.right { text-align: right; }