body {
  background: #000; /* full black */
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  color: #fff;
}

/* Form */
.osg-serial-form {
  background: #111;
  border-radius: 12px;
  margin: 80px auto;
  text-align: center;
  box-shadow: 0 4px 20px rgba(0,0,0,0.6);
  position: fixed;
  top: 50%;
  left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    padding: 20px;
}
.osg-serial-form h2 {
  font-weight: 500;
  margin-bottom: 20px;
}
.osg-input {
  width: 96%;
  max-width: 100%;
  padding: 12px;
  margin-bottom: 20px;
  border-radius: 8px;
  border: none;
  background: #222;
  color: #fff;
}
.osg-btn {
  width: 100%;
  padding: 12px;
  background: #0071e3;
  border: none;
  border-radius: 8px;
  color: #fff;
  font-size: 16px;
  cursor: pointer;
  transition: background .3s;
}
.osg-btn:hover {
  background: #005bb5;
}

/* Popup */
.osg-popup {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.8);
  justify-content: center;
  align-items: center;
  z-index: 9999;
}
.osg-popup-content {
  background: #000000;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.9);
}
.osg-close {
  float: right;
  font-size: 22px;
  cursor: pointer;
  color: #aaa;
}
.osg-close:hover {
  color: #fff;
}
/* ====== Apple Style Result Popup ====== */
.osg-apple-style {
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  background: #1c1c1e;
  color: #fff;
  padding: 25px;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,.8);
}

.osg-apple-style .osg-header {
  display: flex;
  align-items: center;
  gap: 15px;
  margin-bottom: 20px;
}

.osg-apple-style .osg-thumb {
  width: 80px;
  height: auto;
  border-radius: 6px;
}

.osg-apple-style .osg-name {
  font-size: 20px;
  font-weight: 600;
  margin: 0 0 5px 0;
  color: #fff;
}

.osg-apple-style p {
  margin: 4px 0;
  font-size: 15px;
  color: #d1d1d6;
}

.osg-apple-style .osg-desc {
  margin: 15px 0;
  font-size: 14px;
  line-height: 1.6;
  color: #e5e5e7;
}

.osg-apple-style .osg-warranty-box {
  background: #2c2c2e;
  padding: 15px;
  border-radius: 10px;
  margin-top: 20px;
}

.osg-apple-style .osg-warranty-box h3 {
  font-size: 16px;
  margin: 0 0 10px 0;
  color: #fff;
}

.osg-apple-style .osg-warranty-box p {
  font-size: 14px;
  margin: 4px 0;
  color: #d1d1d6;
}

.osg-apple-style .osg-warranty-box hr {
  border: none;
  border-top: 1px solid #3a3a3c;
  margin: 10px 0;
}

.osg-apple-style .osg-warranty-box ul {
  padding-left: 20px;
  margin: 8px 0;
}

.osg-apple-style .osg-warranty-box li {
  margin: 5px 0;
  font-size: 14px;
  color: #d1d1d6;
}

.osg-apple-style a {
  color: #0a84ff;
  text-decoration: none;
  font-size: 14px;
}
.osg-input,
.osg-btn {
  display: block;
  width: 100%;
  box-sizing: border-box;
  margin: 0 0 10px;
}
@media (max-width: 768px) {
  .osg-serial-form{
      width: 77%;}}
.osg-input {
  font-size: 16px !important;  /* fix zoom trên iOS */
  line-height: 1.4;
  padding: 10px 12px;
}
.osg-extra-info {
  margin-top: 15px;
  font-size: 14px;
  color: #ddd;
}

.osg-cert-buttons {
  display: flex;
  gap: 10px;
  margin: 10px 0 15px;
}

.osg-cert-btn {
  background: #007bff;
  color: #fff !important;
  padding: 8px 14px;
  border-radius: 6px;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: background 0.3s ease;
}

.osg-cert-btn:hover {
  background: #0056b3;
}