/*
  Claude Chat —— 极简单色聊天界面。system 字体、无外部资源、无内联样式。
*/
:root {
  --bg: #f4f3f0;
  --panel: #ffffff;
  --panel-soft: #faf9f7;
  --text: #1c1c1e;
  --muted: #6e6e73;
  --line: #e4e2dd;
  --line-strong: #d3d0ca;
  --accent: #1c1c1e;
  --accent-text: #ffffff;
  --danger: #b3261e;
  --ok: #2e7d32;
  --bubble-user: #1c1c1e;
  --bubble-user-text: #f7f7f5;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 8px 24px rgba(0, 0, 0, 0.04);
  --radius: 16px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0b0c;
    --panel: #151517;
    --panel-soft: #1b1b1e;
    --text: #f2f2f0;
    --muted: #9a9a9f;
    --line: #2a2a2d;
    --line-strong: #3a3a3e;
    --accent: #f2f2f0;
    --accent-text: #111112;
    --danger: #ff8a80;
    --ok: #7bd88f;
    --bubble-user: #f2f2f0;
    --bubble-user-text: #111112;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
  }
}

* { box-sizing: border-box; }

/* 关键：隐藏必须压过 .login{display:grid} / .chat{display:flex}，否则登录页和聊天页会同时渲染 */
[hidden] { display: none !important; }

html, body {
  height: 100%;
  margin: 0;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

#app { min-height: 100%; }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ───────── 登录 ───────── */
.login {
  min-height: 100vh;   /* 老 Safari 回退 */
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.login-card {
  width: min(380px, 100%);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 32px 28px 26px;
  box-shadow: var(--shadow);
  font-style: normal;
}

.login-card h1 {
  margin: 0 0 4px;
  font-size: 26px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.login-card .sub {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 13px;
}

.field { display: block; margin-bottom: 14px; }
.field span {
  display: block;
  margin-bottom: 6px;
  color: var(--muted);
  font-size: 12px;
}

input[type="password"], textarea, select {
  font: inherit;
  color: inherit;
  background: var(--panel-soft);
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

input[type="password"] {
  width: 100%;
  padding: 11px 12px;
  letter-spacing: 0.02em;
}

input[type="password"]:focus, textarea:focus, select:focus {
  border-color: var(--text);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--text) 10%, transparent);
}

button {
  font: inherit;
  cursor: pointer;
  border-radius: 10px;
  border: 1px solid transparent;
  transition: opacity 0.15s ease, background-color 0.15s ease, border-color 0.15s ease;
}

button:disabled { opacity: 0.5; cursor: default; }

.primary {
  background: var(--accent);
  color: var(--accent-text);
  padding: 11px 16px;
  border: none;
  font-weight: 500;
}

.primary:hover:not(:disabled) { opacity: 0.88; }

#loginBtn { width: 100%; }

.error {
  margin: 14px 0 0;
  color: var(--danger);
  font-size: 13px;
}

/* ───────── 聊天 ───────── */
.chat {
  display: flex;
  flex-direction: column;
  height: 100vh;       /* 老 Safari 回退 */
  height: 100dvh;
  max-width: 820px;
  margin: 0 auto;
}

.bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  position: sticky;
  top: 0;
  z-index: 2;
}

.bar-left, .bar-right { display: flex; align-items: center; gap: 8px; }

.brand {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--line-strong);
  display: inline-block;
  transition: background-color 0.2s ease;
}

.dot.ok { background: var(--ok); }
.dot.bad { background: var(--danger); }

select {
  padding: 6px 8px;
  font-size: 13px;
  border-radius: 8px;
  color: var(--muted);
}

.ghost {
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--line);
  padding: 6px 11px;
  font-size: 13px;
}

.ghost:hover:not(:disabled) {
  color: var(--text);
  border-color: var(--line-strong);
}

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 26px 18px 14px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  overscroll-behavior: contain;
}

.empty {
  margin: auto;
  text-align: center;
  color: var(--muted);
  padding: 24px;
}

.empty p { margin: 0 0 6px; }
.empty-sub { font-size: 12.5px; opacity: 0.85; max-width: 34ch; margin: 0 auto !important; }

.msg {
  display: flex;
  flex-direction: column;
  max-width: 100%;
  animation: rise 0.18s ease-out;
}

@keyframes rise {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
  .msg { animation: none; }
}

.msg.user { align-items: flex-end; }

.msg .bubble {
  max-width: 78%;
  border-radius: var(--radius);
  padding: 10px 14px;
}

.msg.user .bubble {
  background: var(--bubble-user);
  color: var(--bubble-user-text);
  border-bottom-right-radius: 6px;
}

.msg.assistant .bubble {
  max-width: 100%;
  padding: 0 2px;
  border-radius: 0;
}

.msg .body {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.msg.assistant .body { font-size: 15.5px; }

.msg.assistant.streaming .body::after {
  content: "▍";
  color: var(--muted);
  animation: blink 1s steps(2, start) infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

.msg .meta {
  margin-top: 6px;
  color: var(--muted);
  font-size: 11.5px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

.msg .err {
  margin-top: 6px;
  color: var(--danger);
  font-size: 13px;
}

/* ───────── 输入 ───────── */
.composer {
  position: sticky;
  bottom: 0;
  padding: 10px 16px max(12px, env(safe-area-inset-bottom));
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-top: 1px solid var(--line);
}

.composer-form {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  background: var(--panel);
  border: 1px solid var(--line-strong);
  border-radius: 16px;
  padding: 8px 8px 8px 14px;
  box-shadow: var(--shadow);
}

textarea {
  flex: 1;
  resize: none;
  border: none;
  background: transparent;
  padding: 6px 0;
  max-height: 180px;
  box-shadow: none !important;
  line-height: 1.5;
}

.composer-actions { display: flex; gap: 6px; padding-bottom: 2px; }

.send { padding: 8px 16px; border-radius: 10px; }

.stop {
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--line-strong);
  padding: 8px 14px;
}

.stop:hover { color: var(--text); }

.hint {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 7px 4px 0;
  color: var(--muted);
  font-size: 11.5px;
}

.cost { font-variant-numeric: tabular-nums; }

@media (max-width: 520px) {
  /* iOS Safari 在字号 <16px 时会自动放大页面，这里强制 16px */
  input[type="password"], textarea, select { font-size: 16px; }
  .bar { padding: 10px 12px; }
  .messages { padding: 18px 12px 10px; }
  .composer { padding-left: 12px; padding-right: 12px; }
  .msg .bubble { max-width: 88%; }
  .brand { font-size: 14px; }
  .ghost { padding: 6px 9px; }
}

/* 404 页 */
.home-link {
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px;
  font-size: 14px;
}
.home-link:hover { border-color: var(--text); }

/* 构建标记（排查缓存问题用，改资源时跟着 index.html 里的 ?v= 一起改） */
.build {
  margin: 16px 2px 0;
  text-align: right;
  font-size: 10.5px;
  color: var(--muted);
  opacity: 0.65;
  letter-spacing: 0.02em;
}