:root {
  --bg-top: #f4fbff;
  --bg-bottom: #ecfff2;
  --ink: #1c2b33;
  --muted: #58717d;
  --panel: #ffffff;
  --line: #d7e8ef;
  --brand: #00696b;
  --brand-2: #0d8f55;
  --user: #d8f7e9;
  --bot: #eff7ff;
  --shadow: 0 10px 30px rgba(15, 45, 59, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--ink);
  background: linear-gradient(160deg, var(--bg-top), var(--bg-bottom));
  min-height: 100vh;
}

.shell {
  width: min(960px, 94vw);
  margin: 28px auto;
  display: grid;
  gap: 16px;
}

.hero,
.examples,
.chat {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
}

.hero {
  padding: 20px;
}

.hero h1 {
  margin: 0 0 8px;
  font-size: clamp(1.4rem, 2.3vw, 2rem);
}

.hero p {
  margin: 0;
  color: var(--muted);
  line-height: 1.5;
}

.examples {
  padding: 14px;
}

#faq-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.example-chip {
  border: 1px solid var(--line);
  background: #f8fdff;
  color: #204154;
  border-radius: 999px;
  padding: 8px 12px;
  cursor: pointer;
}

.example-chip:hover {
  border-color: #9ac2d2;
  background: #f2fbff;
}

.chat {
  padding: 14px;
  display: grid;
  gap: 12px;
}

.messages {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px;
  min-height: 360px;
  max-height: 58vh;
  overflow: auto;
  background: #fcfeff;
}

.message {
  max-width: 86%;
  margin: 8px 0;
  padding: 10px 12px;
  border-radius: 10px;
  line-height: 1.45;
}

.message-text {
  margin: 0;
  white-space: pre-wrap;
}

.message.user {
  margin-left: auto;
  background: var(--user);
  border: 1px solid #b5e8cd;
}

.message.bot {
  margin-right: auto;
  background: var(--bot);
  border: 1px solid #c8e0f7;
}

.source-label {
  margin-top: 8px;
  font-size: 0.82rem;
  color: #315a78;
  font-weight: 600;
}

.source-links {
  margin-top: 6px;
  display: grid;
  gap: 4px;
}

.source-links a {
  color: #0d4e8a;
  text-decoration: none;
  overflow-wrap: anywhere;
  font-size: 0.84rem;
}

.source-links a:hover {
  text-decoration: underline;
}

.composer {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
}

.composer input {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px;
  font: inherit;
}

.composer button {
  border: 0;
  border-radius: 10px;
  padding: 0 16px;
  background: linear-gradient(120deg, var(--brand), var(--brand-2));
  color: #fff;
  font-weight: 600;
  cursor: pointer;
}

.composer button:hover {
  filter: brightness(1.05);
}

@media (max-width: 680px) {
  .shell {
    width: min(960px, 96vw);
    margin: 12px auto;
  }

  .messages {
    min-height: 320px;
    max-height: 52vh;
  }

  .message {
    max-width: 95%;
  }
}