body {
  font-family: Arial, sans-serif;
  background: #f9f9f9;
  color: #222;
  margin: 0;
  padding: 0;
}

header {
  background: #4a90e2;
  color: #fff;
  padding: 1em 0;
  text-align: center;
}

nav {
  margin-top: 0.5em;
}

nav a, nav button {
  color: #fff;
  text-decoration: none;
  margin: 0 1em;
  background: none;
  border: none;
  font-size: 1em;
  cursor: pointer;
}

main {
  max-width: 600px;
  margin: 2em auto;
  background: #fff;
  padding: 2em;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

section {
  margin-bottom: 2em;
}

form label {
  display: block;
  margin-top: 1em;
}

form input, form select, form button {
  width: 100%;
  padding: 0.5em;
  margin-top: 0.5em;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box;
}

form button {
  background: #4a90e2;
  color: #fff;
  border: none;
  margin-top: 1em;
  cursor: pointer;
  font-weight: bold;
}

form button:hover {
  background: #357ab8;
}

#transaction-list {
  list-style: none;
  padding: 0;
}

#transaction-list li {
  padding: 0.75em 1em;
  border-bottom: 1px solid #eee;
  display: flex;
  justify-content: space-between;
  align-items: center;
  word-break: break-word;
}

#transaction-list li:last-child {
  border-bottom: none;
}

footer {
  text-align: center;
  padding: 1em 0;
  background: #f1f1f1;
  color: #888;
  position: fixed;
  width: 100%;
  bottom: 0;
}

/* Responsive */
@media (max-width: 700px) {
  main {
    padding: 1em;
  }
  h1, h2 {
    font-size: 1.2em;
  }
  #transaction-list li {
    flex-direction: column;
    align-items: flex-start;
    padding: 0.75em 0.5em;
  }
  form input, form select, form button {
    font-size: 1em;
  }
}