:root {
  --ink: #15231c;
  --ink-2: #1e3228;
  --panel: #f3efe6;
  --paper: #faf7f0;
  --line: rgba(21, 35, 28, 0.12);
  --muted: #5c6b63;
  --accent: #c45c26;
  --accent-deep: #9a4012;
  --user-bubble: #e7efe9;
  --assist-bubble: #ffffff;
  --shadow: 0 18px 50px rgba(21, 35, 28, 0.12);
  --radius: 18px;
  --font-brand: "Fraunces", Georgia, serif;
  --font-ui: "Manrope", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  font-family: var(--font-ui);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(196, 92, 38, 0.14), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(30, 50, 40, 0.1), transparent 50%),
    linear-gradient(180deg, #ebe4d6 0%, var(--paper) 45%, #e8efe9 100%);
}

.app {
  display: grid;
  grid-template-columns: 280px 1fr;
  height: 100%;
  max-width: 1600px;
  margin: 0 auto;
}

.sidebar {
  display: flex;
  flex-direction: column;
  background: linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  color: #e8efe9;
  padding: 1rem 0.85rem;
  border-right: 1px solid rgba(255,255,255,0.06);
}

.sidebar-top { padding: 0.25rem 0.35rem 0.85rem; display: grid; gap: 0.75rem; }

.sidebar-brand {
  display: block;
  text-decoration: none;
  border-radius: 14px;
  overflow: hidden;
  background: #fff;
  padding: 0.55rem;
  border: 1px solid rgba(255,255,255,0.12);
}

.logo {
  display: block;
  width: auto;
  height: auto;
  object-fit: contain;
}
.logo-sidebar {
  width: 100%;
  max-height: 7.5rem;
  margin: 0 auto;
}
.logo-top {
  width: 2rem;
  height: 2rem;
  border-radius: 8px;
  background: #fff;
  padding: 0.12rem;
  border: 1px solid var(--line);
}
.logo-hero {
  width: min(280px, 72vw);
  height: auto;
  margin: 0 auto;
  filter: drop-shadow(0 18px 40px rgba(21, 35, 28, 0.12));
}

.topbar-brand {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  min-width: 0;
}

.btn-new {
  width: 100%;
  border: 1px solid rgba(255,255,255,0.18);
  background: rgba(255,255,255,0.06);
  color: inherit;
  border-radius: 12px;
  padding: 0.75rem 0.9rem;
  font: 600 0.95rem var(--font-ui);
  cursor: pointer;
  text-align: left;
  transition: background 0.15s ease, border-color 0.15s ease;
}
.btn-new:hover { background: rgba(255,255,255,0.12); border-color: rgba(255,255,255,0.3); }
.btn-new .plus { margin-right: 0.45rem; color: var(--accent); }

.chat-list {
  flex: 1;
  overflow: auto;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 0 0.25rem;
}

.chat-item {
  border: 0;
  background: transparent;
  color: #d5e0d8;
  text-align: left;
  padding: 0.7rem 0.75rem;
  border-radius: 10px;
  cursor: pointer;
  font: 500 0.88rem/1.3 var(--font-ui);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.chat-item:hover, .chat-item.active { background: rgba(255,255,255,0.1); color: #fff; }

.sidebar-foot {
  padding: 1rem 0.6rem 0.4rem;
  border-top: 1px solid rgba(255,255,255,0.08);
  margin-top: 0.5rem;
}
.brand-sub { margin: 0 0 0.7rem; color: #9aada2; font-size: 0.78rem; }
.linkish {
  background: none;
  border: 0;
  color: #cfe0d5;
  cursor: pointer;
  padding: 0;
  font: 600 0.85rem var(--font-ui);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.main {
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-width: 0;
  background: transparent;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.85rem 1.25rem;
}
.topbar-title {
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: 1.15rem;
}
.topbar-spacer { flex: 1; }
.icon-btn {
  border: 1px solid var(--line);
  background: rgba(255,255,255,0.55);
  border-radius: 10px;
  width: 2.2rem;
  height: 2.2rem;
  cursor: pointer;
}
.mobile-only { display: none; }

.stage {
  overflow: auto;
  padding: 0 1.25rem 1rem;
}

.welcome {
  min-height: min(62vh, 560px);
  display: grid;
  place-content: center;
  text-align: center;
  gap: 0.85rem;
  padding: 2rem 1rem;
}
.welcome-lead {
  margin: 0 auto;
  max-width: 28rem;
  color: var(--muted);
  font-size: 1.05rem;
}
.suggestions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  justify-content: center;
  margin-top: 0.75rem;
}
.suggestions button {
  border: 1px solid var(--line);
  background: rgba(255,255,255,0.65);
  backdrop-filter: blur(6px);
  border-radius: 999px;
  padding: 0.65rem 0.95rem;
  font: 500 0.88rem var(--font-ui);
  cursor: pointer;
  color: var(--ink);
}
.suggestions button:hover { border-color: var(--accent); color: var(--accent-deep); }

.messages {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 0.5rem 0 1.5rem;
}

.msg {
  display: grid;
  gap: 0.35rem;
  animation: rise 0.28s ease;
}
@keyframes rise {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}
.msg .role {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  padding-left: 0.35rem;
}
.msg .bubble {
  padding: 0.95rem 1.05rem;
  border-radius: var(--radius);
  line-height: 1.55;
  white-space: pre-wrap;
  word-break: break-word;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
}
.msg.user .bubble { background: var(--user-bubble); }
.msg.assistant .bubble { background: var(--assist-bubble); }
.msg .tools {
  display: flex;
  gap: 0.5rem;
  padding-left: 0.25rem;
}
.msg .tools button {
  border: 0;
  background: transparent;
  color: var(--muted);
  font: 600 0.78rem var(--font-ui);
  cursor: pointer;
}
.msg .tools button:hover { color: var(--accent-deep); }

.msg.pending .bubble {
  color: var(--muted);
  font-style: italic;
}

.composer-wrap {
  padding: 0.5rem 1.25rem 1rem;
}
.composer {
  max-width: 820px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.55rem;
  align-items: end;
  background: rgba(255,255,255,0.82);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 0.55rem 0.55rem 0.55rem 1rem;
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
}
.composer textarea {
  border: 0;
  resize: none;
  outline: none;
  background: transparent;
  font: 500 1rem/1.45 var(--font-ui);
  max-height: 180px;
  width: 100%;
  color: var(--ink);
}
.btn-send {
  width: 2.5rem;
  height: 2.5rem;
  border: 0;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
}
.btn-send:disabled { opacity: 0.45; cursor: default; }
.btn-send:not(:disabled):hover { background: var(--accent-deep); }

.disclaimer {
  max-width: 820px;
  margin: 0.55rem auto 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.75rem;
}

dialog {
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  box-shadow: var(--shadow);
  width: min(420px, calc(100vw - 2rem));
}
dialog::backdrop { background: rgba(21, 35, 28, 0.45); }
.settings { display: grid; gap: 0.75rem; padding: 1.25rem; }
.settings h2 { margin: 0; font-family: var(--font-brand); }
.settings label { display: grid; gap: 0.3rem; font-size: 0.88rem; font-weight: 600; }
.settings input {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.6rem 0.7rem;
  font: 500 0.95rem var(--font-ui);
  background: #fff;
}
.settings-actions { display: flex; gap: 0.5rem; }
.btn-primary, .btn-ghost {
  border-radius: 10px;
  padding: 0.6rem 0.9rem;
  font: 600 0.9rem var(--font-ui);
  cursor: pointer;
}
.btn-primary { border: 0; background: var(--accent); color: #fff; }
.btn-ghost { border: 1px solid var(--line); background: transparent; }
.settings-hint { margin: 0; color: var(--muted); font-size: 0.8rem; }

@media (max-width: 860px) {
  .app { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    width: min(84vw, 300px);
    z-index: 20;
    transform: translateX(-105%);
    transition: transform 0.2s ease;
  }
  .sidebar.open { transform: none; }
  .mobile-only { display: inline-flex; align-items: center; justify-content: center; }
}