:root {
  --bg: #f6f7f9; --panel: #ffffff; --text: #1d2330; --muted: #5f6878; --line: #e2e5ea;
  --accent: #1f6feb; --accent-text: #ffffff; --user: #e8f0fe; --warn-bg: #fff4e5; --warn: #8a4b00;
  --ok: #1a7f37; --code: #f2f4f7;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171c; --panel: #1c2027; --text: #e6e9ee; --muted: #9aa3b2; --line: #2d333d;
    --accent: #4c8dff; --accent-text: #0b1020; --user: #23304a; --warn-bg: #3a2a12; --warn: #ffc069;
    --ok: #5cc27a; --code: #232831;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body { background: var(--bg); color: var(--text); font: 15px/1.7 -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif; }
button { font: inherit; cursor: pointer; }
.btn-primary { background: var(--accent); color: var(--accent-text); border: 0; border-radius: 8px; padding: 8px 16px; font-weight: 600; }
.btn-primary:disabled { opacity: .5; cursor: default; }
.btn-link { background: none; border: 0; color: var(--muted); padding: 4px 8px; }

/* login */
.login-body { display: flex; align-items: center; justify-content: center; padding: 16px; }
.login-card { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 28px; width: 100%; max-width: 380px; }
.login-card h1 { font-size: 20px; margin: 0 0 8px; }
.login-sub { color: var(--muted); font-size: 13px; margin: 0 0 8px; }
.login-msg { color: #d1242f; font-size: 14px; min-height: 1em; margin: 0 0 8px; }
.login-card label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 12px; }
.login-card input { display: block; width: 100%; margin-top: 4px; padding: 10px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); color: var(--text); font-size: 16px; }
.login-card button { width: 100%; margin-top: 8px; padding: 10px; }

/* layout */
.layout { display: flex; height: 100%; }
.side { width: 260px; flex: none; background: var(--panel); border-right: 1px solid var(--line); padding: 16px; display: flex; flex-direction: column; gap: 8px; }
.side h2 { font-size: 12px; color: var(--muted); margin: 12px 0 0; font-weight: 600; }
.conv-list { list-style: none; margin: 0; padding: 0; overflow-y: auto; flex: 1; }
.conv-list button { display: block; width: 100%; text-align: left; background: none; border: 0; border-radius: 6px; padding: 6px 8px; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; font-size: 14px; }
.conv-list button.active, .conv-list button:hover { background: var(--bg); }
.logout { margin: 0; }
.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.top { display: flex; align-items: center; gap: 8px; padding: 10px 16px; border-bottom: 1px solid var(--line); background: var(--panel); }
.top .title { font-weight: 700; }
.top .who { margin-left: auto; color: var(--muted); font-size: 13px; }
.menu { display: none; font-size: 20px; }
.alerts { background: var(--warn-bg); color: var(--warn); padding: 8px 16px; font-size: 13px; }
.chat { flex: 1; overflow-y: auto; padding: 16px; }
.welcome { max-width: 760px; margin: 24px auto; color: var(--muted); }
.welcome b { color: var(--text); }
.ex-title { margin-bottom: 4px; }
.examples { list-style: none; padding: 0; margin: 0 0 16px; display: flex; flex-wrap: wrap; gap: 8px; }
.examples button { background: var(--panel); border: 1px solid var(--line); color: var(--text); border-radius: 16px; padding: 4px 12px; font-size: 13px; }
.note { font-size: 12px; }
.msg { max-width: 760px; margin: 0 auto 16px; }
.msg.user .bubble { background: var(--user); border-radius: 12px; padding: 10px 14px; white-space: pre-wrap; margin-left: auto; width: fit-content; max-width: 90%; }
.msg.ai .bubble { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 12px 16px; overflow-wrap: anywhere; }
.msg.ai .bubble p { margin: 0 0 8px; }
.msg.ai .bubble ul { margin: 0 0 8px; padding-left: 20px; }
.msg.ai .bubble h3 { font-size: 14px; margin: 12px 0 4px; }
.msg.ai .bubble a { color: var(--accent); }
.msg.ai .bubble code { background: var(--code); padding: 0 4px; border-radius: 4px; }
.progress { font-size: 12px; color: var(--muted); margin: 0 0 6px; }
.progress span { display: inline-block; margin-right: 10px; }
.progress .spin::before { content: "⏳ "; }
.sources { margin-top: 10px; font-size: 12px; color: var(--muted); border-top: 1px dashed var(--line); padding-top: 6px; }
.sources summary { cursor: pointer; }
.sources li { overflow-wrap: anywhere; }
.err { color: #d1242f; }
.draft { border: 1px solid var(--accent); border-radius: 10px; padding: 12px; margin-top: 10px; font-size: 14px; }
.draft h4 { margin: 0 0 6px; font-size: 14px; }
.draft pre { white-space: pre-wrap; background: var(--code); padding: 8px; border-radius: 6px; font: inherit; font-size: 13px; max-height: 320px; overflow-y: auto; }
.draft .checks { font-size: 13px; }
.draft .checks.bad { color: var(--warn); }
.draft .saved { color: var(--ok); font-weight: 600; }
.ask { display: flex; gap: 8px; padding: 12px 16px; border-top: 1px solid var(--line); background: var(--panel); max-width: 100%; }
.ask textarea { flex: 1; resize: vertical; min-height: 44px; max-height: 40vh; padding: 10px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); color: var(--text); font: inherit; font-size: 16px; }
@media (max-width: 760px) {
  .side { position: fixed; z-index: 10; left: 0; top: 0; bottom: 0; transform: translateX(-100%); transition: transform .2s; }
  .side.open { transform: none; box-shadow: 0 0 24px rgba(0,0,0,.25); }
  .menu { display: inline-block; }
  .chat { padding: 12px 16px; }
  .top .who { display: none; }
}