:root {
  --bg: #f6f4ef; --card: #fff; --ink: #23201c; --muted: #8a8378;
  --accent: #e2571f; --accent-d: #c4471a; --line: #e5e0d8; --ok:#2f8f4e; --warn:#c88a12;
}
* { box-sizing: border-box; }
body {
  margin: 0; font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg); color: var(--ink);
}
.hidden { display: none !important; }
.muted { color: var(--muted); }
.spacer { flex: 1; }
button, .btn {
  font: inherit; border: none; border-radius: 8px; padding: .55rem 1rem;
  background: var(--accent); color: #fff; cursor: pointer; text-decoration: none;
}
button:hover, .btn:hover { background: var(--accent-d); }
button.ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); }
button.ghost:hover { background: #efe9e0; }
input[type=email], input[type=text] {
  font: inherit; padding: .6rem .8rem; border: 1px solid var(--line);
  border-radius: 8px; width: 100%;
}

/* Login */
.center { min-height: 100vh; display: grid; place-items: center; }
.card {
  background: var(--card); padding: 2rem; border-radius: 14px; width: min(92vw, 420px);
  box-shadow: 0 10px 40px rgba(0,0,0,.07);
}
.card h1 { margin: 0 0 .3rem; }
.card form { display: flex; flex-direction: column; gap: .7rem; margin-top: 1rem; }
.msg { min-height: 1.2em; margin: .8rem 0 0; }
.msg.ok { color: var(--ok); } .msg.err { color: var(--accent-d); }

/* App layout */
header {
  display: flex; align-items: center; gap: .7rem; padding: .7rem 1.2rem;
  background: var(--card); border-bottom: 1px solid var(--line);
}
header h1 { font-size: 1.15rem; margin: 0; }
main { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; padding: 1rem; }
@media (max-width: 900px) { main { grid-template-columns: 1fr; } }
.col { display: flex; flex-direction: column; gap: 1rem; min-width: 0; }

/* Drop zone */
.drop {
  background: var(--card); border: 2px dashed var(--line); border-radius: 12px;
  padding: 1.2rem; text-align: center; transition: border-color .15s, background .15s;
}
.drop.hot { border-color: var(--accent); background: #fbf1ea; }
.drop input[type=file] { display: none; }
.doclist { list-style: none; padding: 0; margin: .8rem 0 0; text-align: left; }
.doclist li { padding: .3rem .5rem; border-radius: 6px; background: #f0ebe3; margin-bottom: .3rem; font-size: .9rem; }

/* Chat */
.chat { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 1rem; }
.chatlog { max-height: 46vh; overflow-y: auto; display: flex; flex-direction: column; gap: .5rem; margin-bottom: .7rem; }
.bubble { padding: .5rem .8rem; border-radius: 10px; max-width: 85%; white-space: pre-wrap; }
.bubble.user { align-self: flex-end; background: var(--accent); color: #fff; }
.bubble.bot { align-self: flex-start; background: #f0ebe3; }
.bubble.learn { align-self: flex-start; background: #eaf5ec; border: 1px solid #cfe9d5; }
.chat form { display: flex; gap: .5rem; }
.hint { font-size: .8rem; margin: .5rem 0 0; }
code { background: #efe9e0; padding: .1rem .35rem; border-radius: 5px; }

/* Preview + fields */
.toolbar { display: flex; align-items: center; gap: .7rem; }
.preview { display: flex; flex-direction: column; gap: .6rem; max-height: 74vh; overflow-y: auto; }
.preview img { width: 100%; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.fields { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: .6rem 1rem; }
.fields summary { cursor: pointer; font-weight: 600; }
.frow { display: flex; justify-content: space-between; gap: 1rem; padding: .3rem 0; border-bottom: 1px solid var(--line); font-size: .9rem; }
.frow .lbl { color: var(--muted); }
.frow .src { font-size: .75rem; }
.frow.low .val { color: var(--warn); }

/* Spinner */
.spinner { position: fixed; inset: 0; display: grid; place-items: center; gap: 1rem;
  grid-auto-flow: row; background: rgba(246,244,239,.7); z-index: 50; }
.spinner div { width: 40px; height: 40px; border: 4px solid var(--line);
  border-top-color: var(--accent); border-radius: 50%; animation: spin 1s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }