.os-body { background: #eef3f8; min-height: 100vh; }
.os-top {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 20px;
  background: #0a2f5c;
  color: #fff;
}
.os-top a { color: #fff; }
.os-main { max-width: 560px; margin: 0 auto; padding: 28px 16px 48px; }
.os-main h1 { margin: 0 0 8px; }
.os-main > p { color: #4b5b6c; }
.os-form {
  display: grid;
  gap: 12px;
  background: #fff;
  padding: 20px;
  border-radius: 16px;
  margin-top: 16px;
}
.os-form label { display: grid; gap: 6px; font-weight: 700; font-size: 14px; }
.os-form input, .os-form select, .os-form textarea {
  font: inherit;
  border: 1px solid #d5dee8;
  border-radius: 10px;
  padding: 10px 12px;
}
.os-form button {
  background: #0b63ce;
  color: #fff;
  border: 0;
  border-radius: 10px;
  padding: 12px;
  font-weight: 800;
  cursor: pointer;
}
.os-err { color: #be123c; }
.os-ok { color: #157347; }