:root {
  --bg: #f4f6f9;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --text-muted: #64748b;
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
  --accent-soft: #eff4ff;
  --good: #059669;
  --good-soft: #ecfdf5;
  --bad: #dc2626;
  --bad-soft: #fef2f2;
  --radius: 10px;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.5;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 14px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -0.01em;
}

.brand .mark {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), #06b6d4);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 13px;
}

.brand .sub {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 13px;
}

.user-chip {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  color: var(--text-muted);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  font-family: var(--sans);
}

.btn:hover { background: var(--bg); text-decoration: none; }

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

.btn-primary:hover { background: var(--accent-dark); }

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 36px 24px 80px;
}

.container-narrow {
  max-width: 420px;
  margin: 80px auto;
  padding: 0 24px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 20px;
}

.card h2 {
  margin-top: 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.card h2 .accent { color: var(--accent); }

.login-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

.login-card h1 {
  font-size: 19px;
  margin: 0 0 4px;
}

.login-card p.tag {
  color: var(--text-muted);
  font-size: 13px;
  margin: 0 0 24px;
}

label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-muted);
}

input[type="text"], input[type="password"], input[type="search"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  font-family: var(--sans);
  margin-bottom: 16px;
  background: var(--bg);
  color: var(--text);
}

input:focus {
  outline: none;
  border-color: var(--accent);
  background: var(--surface);
}

.error-box {
  background: var(--bad-soft);
  color: var(--bad);
  border: 1px solid #fecaca;
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 13.5px;
  margin-bottom: 16px;
}

.search-row {
  display: flex;
  gap: 10px;
  margin-bottom: 24px;
}

.search-row input { margin-bottom: 0; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

th {
  text-align: left;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text-muted);
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
}

td {
  padding: 10px 10px;
  border-bottom: 1px solid var(--border);
}

tr:last-child td { border-bottom: none; }

.mono { font-family: var(--mono); font-size: 13.5px; }

.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
}

.badge-active { background: var(--accent-soft); color: var(--accent-dark); }
.badge-completed { background: var(--good-soft); color: var(--good); }
.badge-aborted { background: var(--bad-soft); color: var(--bad); }
.badge-pass { background: var(--good-soft); color: var(--good); }
.badge-neutral { background: #f1f5f9; color: var(--text-muted); }

.student-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 20px;
}

.student-header h1 {
  margin: 0 0 4px;
  font-size: 22px;
}

.student-header .regnum {
  font-family: var(--mono);
  color: var(--text-muted);
  font-size: 14px;
}

.meta-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.meta-grid .item .k {
  font-size: 11.5px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text-muted);
  margin-bottom: 3px;
}

.meta-grid .item .v { font-size: 14px; }

.balance-tile {
  text-align: right;
}

.balance-tile .amount {
  font-family: var(--mono);
  font-size: 28px;
  font-weight: 700;
}

.balance-tile .label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.amount-credit { color: var(--good); }
.amount-owing { color: var(--bad); }

details {
  border-top: 1px solid var(--border);
  padding: 10px 0 4px;
}

details:first-of-type { border-top: none; }

summary {
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

summary::-webkit-details-marker { display: none; }

summary::before {
  content: "▸";
  color: var(--accent);
  font-size: 11px;
  transition: transform 0.15s ease;
}

details[open] summary::before { transform: rotate(90deg); }

.empty-state {
  color: var(--text-muted);
  font-size: 14px;
  padding: 24px 0;
  text-align: center;
}

.note {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 8px;
}

.section-title {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  margin: 28px 0 10px;
  font-weight: 600;
}

.back-link { font-size: 13.5px; margin-bottom: 18px; display: inline-block; }