*, *::before, *::after {
  box-sizing: border-box;
}

body {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  background: #0f172a;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  padding: 20px;
}

.prompt-container {
  width: 100%;
  max-width: 600px;
  position: relative;
}

.glow-wrapper {
  position: relative;
  border-radius: 20px;
  padding: 2px;
  background: linear-gradient(90deg, #3b82f6, #8b5cf6, #ec4899, #3b82f6);
  background-size: 300% 300%;
  animation: gradientGlow 4s ease infinite;
  z-index: 1;
}

.glow-wrapper::before {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: 24px;
  background: inherit;
  filter: blur(12px);
  opacity: 0.6;
  z-index: -1;
  animation: gradientGlow 4s ease infinite;
}

@keyframes gradientGlow {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

.input-box {
  background: #1e293b;
  border-radius: 18px;
  display: flex;
  flex-direction: column;
  padding: 12px;
}

#prompt-area {
  background: transparent;
  border: none;
  color: #f8fafc;
  resize: none;
  outline: none;
  font-family: inherit;
  font-size: 1rem;
  padding: 8px;
  line-height: 1.5;
  min-height: 44px;
  max-height: 200px;
  overflow-y: auto;
}

#prompt-area::placeholder {
  color: #64748b;
}

.actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 8px;
  border-top: 1px solid #334155;
  margin-top: 4px;
}

.attach-btn, 
.submit-btn {
  background: transparent;
  border: none;
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 50%;
  width: 36px;
  height: 36px;
  transition: background 0.2s;
}

.attach-btn {
  color: #94a3b8;
}

.attach-btn:hover {
  background: #334155;
  color: #f8fafc;
}

.submit-btn {
  background: #3b82f6;
  color: #ffffff;
}

.submit-btn:hover {
  background: #2563eb;
}

const textarea = document.getElementById("prompt-area");

textarea.addEventListener("input", function() {
  this.style.height = "auto";
  this.style.height = this.scrollHeight + "px";
});