body {
  margin: 0;
  font-family: 'Playpen Sans', sans-serif;
  background-color: #000;
  color: #fff;
}

header {
  background-color: #111;
  border-bottom: 1px solid #333;
  padding: 10px 10%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 20px;
  color: #fff;
}

.logo img {
  height: 24px;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 20px;
}

nav ul li {
  position: relative;
}

nav a {
  text-decoration: none;
  color: #fff;
  font-weight: 500;
  transition: color 0.2s;
}

nav a:hover {
  color: #4864e6;
}

/* Submenu Fix */
.submenu {
  display: none;
  position: absolute;
  top: 100%;
  /* tránh khoảng hở */
  left: 0;
  background: #111;
  border: 1px solid #333;
  padding: 10px;
  border-radius: 4px;
  z-index: 999;
  min-width: 160px;
}

.dropdown:hover>.submenu,
.submenu:hover {
  display: block;
}

main {
  padding: 40px 20px;
  margin: auto;
}

h1 {
  font-size: 24px;
  margin-bottom: 20px;
}

label {
  display: block;
  margin-top: 20px;
  margin-bottom: 8px;
  font-weight: 500;
}

.convert-bar {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 20px;
  margin-bottom: 20px;
}

.select-version {
  flex-grow: 1;
}

select,
button {
  font-size: 16px;
  padding: 10px;
  border-radius: 6px;
  box-sizing: border-box;
  border: 1px solid #333;
  background-color: #111;
  color: #fff;
}

button {
  background-color: #4864e6;
  color: white;
  cursor: pointer;
  border: none;
  font-weight: 600;
  transition: background 0.2s;
}

button:hover {
  background-color: #3547b3;
}

.copy-button {
  margin-top: 10px;
  padding: 8px 12px;
  font-size: 14px;
  background-color: #222;
  border: 1px solid #555;
  border-radius: 4px;
  color: white;
  cursor: pointer;
  transition: background 0.2s;
}

.copy-button:hover {
  background-color: #333;
}

.xml-columns {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  width: 100%;
}

.column {
  flex: 1 1 48%;
  display: flex;
  flex-direction: column;
}

.CodeMirror {
  height: 50vh !important;
  width: 100%;
  background-color: #111;
  color: white;
  font-family: monospace;
  font-size: 14px;
  border: 1px solid #333;
  border-radius: 6px;
}

.typewriter {
  font-size: 2.5rem;
  font-weight: 600;
  border-right: 2px solid #fff;
  white-space: nowrap;
  overflow: hidden;
  width: fit-content;
  padding-right: 5px;
}