* {
  box-sizing: border-box;
  font-family: Inter, Arial, sans-serif;
}

body {
  margin: 0;
  background: linear-gradient(135deg, #020617, #020617);
  color: #e5e7eb;
}

header {
  background: rgba(2, 6, 23, 0.9);
  backdrop-filter: blur(10px);
  padding: 20px;
  font-size: 26px;
  font-weight: bold;
  text-align: center;
  color: #38bdf8;
  border-bottom: 1px solid #1e293b;
}

.tabs {
  display: flex;
  background: #020617;
}

.tab {
  flex: 1;
  padding: 14px;
  text-align: center;
  cursor: pointer;
  font-weight: 600;
  color: #94a3b8;
  border-bottom: 2px solid transparent;
  transition: 0.3s;
}

.tab:hover {
  color: white;
}

.tab.active {
  border-bottom: 2px solid #38bdf8;
  color: #38bdf8;
}

.container {
  max-width: 1000px;
  margin: auto;
  padding: 25px;
}

.card {
  background: rgba(15, 23, 42, 0.9);
  border: 1px solid #1e293b;
  border-radius: 14px;
  padding: 22px;
  margin-bottom: 20px;
  box-shadow: 0 0 40px rgba(56, 189, 248, 0.06);
}

h3 {
  margin-top: 0;
  color: #7dd3fc;
}

input, button {
  width: 100%;
  margin-top: 12px;
  padding: 12px;
  border-radius: 8px;
  border: none;
  font-size: 15px;
}

input {
  background: #020617;
  color: white;
  border: 1px solid #1e293b;
}

button {
  background: linear-gradient(135deg, #38bdf8, #0ea5e9);
  color: black;
  font-weight: bold;
  cursor: pointer;
  transition: 0.2s;
}

button:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(56, 189, 248, 0.25);
}

pre {
  background: black;
  padding: 12px;
  border-radius: 8px;
  overflow-x: auto;
  margin-top: 12px;
}

.status-badge {
  display: inline-block;
  margin-top: 10px;
  padding: 6px 14px;
  border-radius: 999px;
  font-weight: bold;
}

.status-pending {
  background: #facc15;
  color: black;
}

.status-paid {
  background: #22c55e;
  color: black;
}

.card {
  background: linear-gradient(135deg, #111, #222);
  padding: 15px;
  border-radius: 12px;
  color: #fff;
  font-weight: bold;
  min-width: 180px;
  text-align: center;
  box-shadow: 0 8px 20px rgba(0,0,0,0.4);
}