:root {
  --bg: #0a0e17; --card: rgba(255,255,255,0.045); --ink: #eef1f8; --muted: #8b93a7;
  --line: rgba(255,255,255,0.09); --accent: #8b7bff; --accent-soft: rgba(139,123,255,0.14);
  --green: #2ee6a6; --green-soft: rgba(46,230,166,0.14);
  --red: #ff5c7a; --red-soft: rgba(255,92,122,0.14);
  --gray: #6b7280; --gray-soft: rgba(255,255,255,0.06);
  --accent2: #22d3ee;
  --radius: 16px;
  --shadow: 0 1px 0 rgba(255,255,255,0.04) inset, 0 10px 30px rgba(0,0,0,0.35);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg); color: var(--ink); min-height: 100vh; -webkit-font-smoothing: antialiased;
  background:
    radial-gradient(circle at 12% 0%, rgba(139,123,255,0.16), transparent 42%),
    radial-gradient(circle at 88% 18%, rgba(34,211,238,0.12), transparent 40%),
    var(--bg);
  background-attachment: fixed;
}
h1 { font-family: 'Space Grotesk', 'Inter', sans-serif; font-size: 26px; margin-bottom: 8px; }
button { font-family: inherit; cursor: pointer; }
input { font-family: inherit; }
a { color: var(--accent); }

.bk-wrap { max-width: 900px; margin: 0 auto; padding: 0 24px; }

/* ---------- Header ---------- */
.bk-header {
  padding: 20px 0; border-bottom: 1px solid var(--line);
  background: rgba(10,14,23,0.72); backdrop-filter: blur(14px);
}
.bk-logo { height: 40px; width: auto; display: block; }
.bk-admin-topbar { display: flex; align-items: center; justify-content: space-between; }
.bk-logout-link { font-size: 14px; color: var(--muted); text-decoration: none; }
.bk-logout-link:hover { color: var(--ink); }

/* ---------- Intro ---------- */
.bk-intro { padding: 40px 0 24px; }
.bk-intro p { color: var(--muted); font-size: 15px; margin-top: 6px; }

/* ---------- Vorteile ---------- */
.bk-benefits {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-bottom: 32px;
}
.bk-benefit {
  display: flex; align-items: center; gap: 12px; padding: 16px;
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
}
.bk-benefit-icon {
  width: 38px; height: 38px; border-radius: 10px; background: var(--accent-soft); color: var(--accent);
  display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.bk-benefit-title { font-size: 13px; font-weight: 700; }
.bk-benefit-sub { font-size: 12px; color: var(--muted); margin-top: 1px; }

/* ---------- Footer ---------- */
.bk-footer { border-top: 1px solid var(--line); padding: 40px 0 48px; margin-top: 16px; }
.bk-footer-inner { text-align: center; }
.bk-footer-logo { height: 28px; margin: 0 auto 14px; display: block; opacity: 0.85; }
.bk-footer-text { color: var(--muted); font-size: 13px; margin-bottom: 12px; }
.bk-footer-links { font-size: 13px; }
.bk-footer-links a { color: var(--muted); text-decoration: none; }
.bk-footer-links a:hover { color: var(--accent); }
.bk-footer-dot { color: var(--line); margin: 0 8px; }

/* ---------- Tabs ---------- */
.bk-tabs { display: flex; gap: 8px; margin-bottom: 20px; }
.bk-tab {
  padding: 10px 18px; border-radius: 10px; border: 1px solid var(--line);
  background: rgba(255,255,255,0.03); color: var(--muted); font-size: 14px; font-weight: 600;
}
.bk-tab.active { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }

/* ---------- Wochenraster ---------- */
.bk-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; padding-bottom: 60px; }
.bk-day {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden;
}
.bk-day-head { padding: 14px; text-align: center; border-bottom: 1px solid var(--line); }
.bk-day-name { font-size: 12px; font-weight: 700; text-transform: uppercase; color: var(--muted); letter-spacing: 0.05em; }
.bk-day-date { font-size: 16px; font-weight: 700; margin-top: 2px; }
.bk-slots { display: flex; flex-direction: column; gap: 6px; padding: 10px; }
.bk-slot {
  padding: 10px 8px; border-radius: 8px; border: 1.5px solid var(--line);
  background: rgba(255,255,255,0.03); color: var(--ink); font-size: 13px; font-weight: 600;
  transition: all 0.15s;
}
.bk-slot:not(.disabled):hover { border-color: var(--accent); background: var(--accent-soft); color: var(--accent); }
.bk-slot.disabled { opacity: 0.4; cursor: default; text-decoration: line-through; }

/* ---------- Modal ---------- */
.bk-modal-overlay {
  position: fixed; inset: 0; background: rgba(5,7,14,0.7); display: none;
  align-items: center; justify-content: center; padding: 20px; z-index: 100;
}
.bk-modal-overlay.open { display: flex; }
.bk-modal {
  background: #10162a; border: 1px solid var(--line); border-radius: 18px;
  width: 100%; max-width: 440px; box-shadow: 0 30px 80px rgba(0,0,0,0.6);
}
.bk-modal-head {
  padding: 20px 24px; border-bottom: 1px solid var(--line);
  display: flex; align-items: center; justify-content: space-between;
}
.bk-modal-head h3 { font-size: 17px; }
.bk-modal-close {
  width: 30px; height: 30px; border-radius: 8px; background: var(--gray-soft);
  color: var(--muted); border: 1px solid var(--line); font-size: 18px;
}
.bk-modal-close:hover { color: var(--ink); background: rgba(255,255,255,0.1); }
.bk-modal-body { padding: 22px 24px; }
.bk-selected-slot { font-size: 14px; font-weight: 600; color: var(--accent); margin-bottom: 16px; }

/* ---------- Formularfelder ---------- */
.bk-field { margin-bottom: 14px; text-align: left; }
.bk-field label { display: block; font-size: 13px; font-weight: 500; color: var(--muted); margin-bottom: 6px; }
.bk-field input {
  width: 100%; padding: 12px 14px; border: 1.5px solid var(--line); border-radius: 10px;
  font-size: 15px; background: rgba(255,255,255,0.03); color: var(--ink);
}
.bk-field input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(139,123,255,0.18); }
.bk-hp { position: absolute; left: -9999px; top: -9999px; }

.bk-submit {
  width: 100%; padding: 13px 20px; border-radius: 10px; font-size: 15px; font-weight: 600;
  background: linear-gradient(135deg, var(--accent), #a78bfa); color: #fff; border: none;
  box-shadow: 0 4px 20px rgba(139,123,255,0.35);
}
.bk-submit:hover { filter: brightness(1.1); }
.bk-submit:disabled { opacity: 0.6; }

.bk-error { color: var(--red); font-size: 13px; margin-bottom: 12px; }
.bk-success p { color: var(--ink); font-size: 15px; line-height: 1.6; margin-bottom: 18px; }
.bk-success-inline { color: var(--green); font-size: 14px; margin-bottom: 16px; }

/* ---------- Admin-Login ---------- */
.bk-login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center; padding: 24px; }
.bk-login-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 20px;
  box-shadow: var(--shadow); padding: 44px 40px; width: 100%; max-width: 380px; text-align: center;
}
.bk-login-logo { height: 60px; margin: 0 auto 20px; display: block; }
.bk-login-sub { color: var(--muted); font-size: 14px; margin-bottom: 24px; }
.bk-login-card form { text-align: left; margin-top: 20px; }

/* ---------- Admin-Tabelle ---------- */
.bk-table { width: 100%; border-collapse: collapse; margin-top: 20px; font-size: 13px; }
.bk-table th {
  text-align: left; padding: 10px 12px; font-size: 11px; text-transform: uppercase;
  letter-spacing: 0.05em; color: var(--muted); border-bottom: 1px solid var(--line);
}
.bk-table td { padding: 12px; border-bottom: 1px solid var(--line); }
.bk-table tr.bk-row-past { opacity: 0.45; }
.bk-empty { color: var(--muted); margin-top: 24px; }
.bk-btn-delete {
  padding: 7px 12px; border-radius: 7px; font-size: 12px; font-weight: 600;
  background: var(--red-soft); color: var(--red); border: 1px solid rgba(255,92,122,0.3);
}
.bk-btn-delete:hover { background: rgba(255,92,122,0.22); }

/* ---------- Responsive ---------- */
@media (max-width: 800px) {
  .bk-grid { grid-template-columns: repeat(2, 1fr); }
  .bk-benefits { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .bk-grid { grid-template-columns: 1fr; }
  .bk-benefits { grid-template-columns: 1fr; }
  .bk-table { display: block; overflow-x: auto; }
}