:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #1a1d23;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --accent: #4f46e5;
  --accent-contrast: #ffffff;
  --radius: 12px;

  --c-vorlesung: #3b82f6;
  --c-aufgabe: #f59e0b;
  --c-termin: #10b981;
  --c-klausur: #ef4444;
  --c-vorkurs: #06b6d4;
  --c-note: #8b5cf6;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --surface: #1c1f26;
    --text: #eef0f3;
    --text-muted: #9aa2b1;
    --border: #2b2f38;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* Login */
.login-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.login-card {
  width: 100%;
  max-width: 360px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.login-card h1 {
  margin: 0 0 4px;
  font-size: 1.5rem;
}

.subtitle {
  margin: 0 0 12px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.login-card label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.login-card input {
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 1rem;
}

.login-card button {
  margin-top: 16px;
  padding: 11px;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: var(--accent-contrast);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
}

.login-card button:hover { opacity: 0.92; }

.error {
  background: #fee2e2;
  color: #991b1b;
  padding: 8px 10px;
  border-radius: 8px;
  font-size: 0.85rem;
  margin: 0;
}

/* Dashboard */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.brand {
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: -0.01em;
}

.logout {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
}

.logout:hover { color: var(--text); }

.tabs {
  display: flex;
  gap: 6px;
  padding: 14px 24px 0;
  overflow-x: auto;
}

.tab {
  white-space: nowrap;
  padding: 8px 14px;
  border-radius: 999px;
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.88rem;
  border: 1px solid transparent;
}

.tab:hover { color: var(--text); }

.tab.active {
  background: var(--accent);
  color: var(--accent-contrast);
}

.content {
  padding: 20px 24px 48px;
  max-width: 960px;
  margin: 0 auto;
}

.empty {
  color: var(--text-muted);
  text-align: center;
  margin-top: 60px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
  margin-top: 16px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 4px solid var(--c-termin);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.card-vorlesung { border-left-color: var(--c-vorlesung); }
.card-aufgabe { border-left-color: var(--c-aufgabe); }
.card-termin { border-left-color: var(--c-termin); }
.card-klausur { border-left-color: var(--c-klausur); }
.card-vorkurs { border-left-color: var(--c-vorkurs); }
.card-note { border-left-color: var(--c-note); }

.card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.badge {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  padding: 3px 8px;
  border-radius: 999px;
  color: #fff;
}

.badge-vorlesung { background: var(--c-vorlesung); }
.badge-aufgabe { background: var(--c-aufgabe); }
.badge-termin { background: var(--c-termin); }
.badge-klausur { background: var(--c-klausur); }
.badge-vorkurs { background: var(--c-vorkurs); }
.badge-note { background: var(--c-note); }

.due {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.card-title {
  margin: 2px 0 0;
  font-size: 1.02rem;
  line-height: 1.35;
}

.course, .detail, .grade {
  margin: 0;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.grade {
  color: var(--c-note);
  font-weight: 600;
}

.detail {
  white-space: pre-line;
  max-height: 4.5em;
  overflow: hidden;
}

.card-link {
  margin-top: 6px;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 600;
}

.card-link:hover { text-decoration: underline; }