html {
  overflow: hidden;
}
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  background: #000;
  color: #f0f0f0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  min-height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 16px 40px;
  text-align: center;
}
body.page-join {
  padding-top: 60px;
}
#nav.hidden {
  display: none;
}
#nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(0,0,0,0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  padding: 12px 20px;
  display: flex;
  justify-content: center;
  gap: 40px;
  z-index: 10;
  border-bottom: 1px solid #222;
}
#nav button {
  background: none;
  border: none;
  color: #ccc;
  font-size: 1.05rem;
  font-weight: 500;
  cursor: pointer;
  padding: 8px 16px;
  transition: all 0.2s;
}
#nav button:hover,
#nav button.active {
  color: #fff;
  font-weight: 600;
}
#nav button.active {
  border-bottom: 2px solid #0c3;
}
main {
  margin-top: 90px;
  max-width: 520px;
  width: 100%;
}
body.page-join main {
  margin-top: 0;
}
h1 {
  font-size: clamp(2.6rem, 8vw, 4.8rem);
  letter-spacing: -1px;
  margin-bottom: 1rem;
  color: #fff;
}
.tag {
  font-size: clamp(1.05rem, 3.5vw, 1.3rem);
  color: #aaa;
  line-height: 1.5;
  margin-bottom: 2.5rem;
}
#join {
  width: 100%;
  max-width: 600px;
  opacity: 0;
  transform: translateY(15px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  border: 1px solid #fff;
  padding: 10px;
  background: rgba(0,0,0,0.8);
  border-radius: 8px;
}
#join.visible {
  opacity: 1;
  transform: translateY(0);
}
form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
label {
  font-size: 1.1rem;
  font-weight: 500;
  color: #ddd;
  text-align: left;
  margin-bottom: 0.4rem;
}
input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  padding: 10px 12px;
  background: #111;
  color: #fff;
  border: 1px solid #333;
  border-radius: 8px;
  font-size: 1.05rem;
  transition: all 0.2s;
}
input:focus,
textarea:focus {
  outline: none;
  border-color: #0c3;
  box-shadow: 0 0 0 3px rgba(12, 195, 51, 0.15);
}
textarea {
  min-height: 110px;
  resize: vertical;
}
.checkbox-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px 20px;
  text-align: left;
  margin: 0.5rem 0 1rem;
}
.checkbox-group label {
  display: flex;
  align-items: center;
  font-size: 1rem;
  color: #ccc;
  cursor: pointer;
  user-select: none;
}
.note {
  font-size: 0.9rem;
  color: #777;
  text-align: left;
  margin-top: -0.6rem;
}
button[type="submit"] {
  margin-top: 1.5rem;
  padding: 16px 60px;
  font-size: 1.15rem;
  font-weight: 600;
  background: linear-gradient(145deg, #0c3, #096);
  color: #000;
  border: none;
  border-radius: 50px;
  cursor: pointer;
  transition: all 0.25s;
  box-shadow: 0 4px 15px rgba(12, 195, 51, 0.25);
}
button[type="submit"]:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(12, 195, 51, 0.4);
}
#message {
  margin-top: 1.2rem;
  font-size: 1.1rem;
  font-weight: 500;
  min-height: 1.6em;
  transition: opacity 0.4s;
}
.success { color: #0c3; }
.error { color: #ff4d4d; }
@media (max-width: 500px) {
  #nav { gap: 24px; padding: 12px 16px; }
  #nav button { font-size: 1rem; padding: 6px 12px; }
  main { margin-top: 80px; }
}