:root {
  --bg-1: #1f3b73;
  --bg-2: #7b56f0;
  --bg-3: #4ac7ff;
  --text: #f6f8ff;
  --muted: #d5defb;
  --glass: rgba(255, 255, 255, 0.16);
  --glass-stroke: rgba(255, 255, 255, 0.38);
  --assistant-bubble: rgba(255, 255, 255, 0.2);
  --user-bubble: rgba(81, 130, 255, 0.45);
  --shadow: 0 20px 40px rgba(20, 32, 68, 0.4);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "SF Pro Text", "Segoe UI", Tahoma, sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 10% 20%, var(--bg-3), transparent 36%),
    radial-gradient(circle at 90% 10%, #8c65ff, transparent 44%),
    linear-gradient(145deg, var(--bg-1), #2f2e84 52%, #0f173a);
  display: grid;
  place-items: center;
  padding: 1.2rem;
}

.app-shell {
  width: min(920px, 100%);
}

.chat-card {
  border-radius: 34px;
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.18), rgba(255, 255, 255, 0.06));
  border: 1px solid rgba(255, 255, 255, 0.25);
  box-shadow: var(--shadow);
  backdrop-filter: blur(22px) saturate(170%);
  -webkit-backdrop-filter: blur(22px) saturate(170%);
  padding: 1rem;
  max-height: 86vh;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.glass {
  background: var(--glass);
  border: 1px solid var(--glass-stroke);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.35);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
}

.chat-header {
  border-radius: 24px;
  padding: 0.9rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.chat-header h1 {
  margin: 0;
  font-size: 1.2rem;
}

.chat-header p {
  margin: 0.2rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.orb {
  width: 16px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, #d7f6ff, #56b3ff);
  box-shadow: 0 0 18px #8bd6ff;
}

.chat-window {
  min-height: 52vh;
  overflow-y: auto;
  padding: 0.3rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  scroll-behavior: smooth;
}

.message {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  max-width: min(86%, 620px);
}

.message-role {
  font-size: 0.75rem;
  color: var(--muted);
  margin-inline: 0.55rem;
}

.message-bubble {
  border-radius: 20px;
  padding: 0.8rem 0.95rem;
  line-height: 1.65;
  white-space: pre-wrap;
  border: 1px solid rgba(255, 255, 255, 0.3);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.message.assistant {
  align-self: flex-start;
}

.message.assistant .message-bubble {
  background: var(--assistant-bubble);
}

.message.user {
  align-self: flex-end;
}

.message.user .message-bubble {
  background: var(--user-bubble);
}

.chat-form {
  border-radius: 22px;
  padding: 0.55rem;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.5rem;
  align-items: end;
}

textarea {
  width: 100%;
  resize: none;
  border: 0;
  color: var(--text);
  background: transparent;
  font: inherit;
  line-height: 1.4;
  min-height: 44px;
  max-height: 160px;
  padding: 0.45rem 0.5rem;
}

textarea::placeholder {
  color: rgba(240, 246, 255, 0.7);
}

textarea:focus,
button:focus-visible {
  outline: 2px solid #bde4ff;
  outline-offset: 2px;
}

button {
  border: 0;
  border-radius: 14px;
  padding: 0.7rem 1rem;
  color: #eef6ff;
  font-weight: 600;
  background: linear-gradient(145deg, #57b5ff, #5e84ff);
  cursor: pointer;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
}

@media (max-width: 600px) {
  .chat-card {
    border-radius: 24px;
    max-height: 92vh;
  }

  .message {
    max-width: 96%;
  }
}