/* 书林智友 · 对话页（学生、教师预演、课堂大屏共用） */
.chat-page { min-height: 100vh; display: flex; flex-direction: column; position: relative; isolation: isolate; }
.chat-page::before { content: ""; position: fixed; inset: -20px; z-index: -2; background: var(--bg) center / cover; filter: blur(6px) saturate(.9); }
.chat-page::after { content: ""; position: fixed; inset: 0; z-index: -1; background: linear-gradient(180deg, rgba(246, 238, 223, .72), rgba(246, 238, 223, .9) 40%, rgba(246, 238, 223, .96)); }

.chat-head { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; gap: 10px; padding: calc(8px + env(safe-area-inset-top)) 10px 8px; background: rgba(255, 250, 240, .8); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); border-bottom: 1px solid var(--line); }
.chat-who { flex: 1; min-width: 0; line-height: 1.25; }
.chat-who b { font-size: 18px; display: block; }
.chat-who small { font-size: 12px; color: var(--ink-3); }

.chat-scroll { flex: 1; overflow-y: auto; padding: 8px 14px 190px; max-width: 760px; width: 100%; margin: 0 auto; }
.chat-intro { text-align: center; padding: 22px 0 12px; }
.chat-intro .avatar { margin: 0 auto 10px; animation: float 5s ease-in-out infinite; }
.chat-intro h2 { font-size: 28px; letter-spacing: .1em; }
.chat-intro p { color: var(--ink-3); font-size: 14px; margin-bottom: 8px; }

.msg { display: flex; align-items: flex-start; gap: 9px; margin: 14px 0; animation: pageIn .35s var(--ease) both; }
.msg.user { flex-direction: row-reverse; }
.msg-bubble { max-width: min(78%, 560px); padding: 11px 15px; border-radius: 4px 18px 18px 18px; background: #fffaf0; border: 1px solid var(--line); box-shadow: 0 3px 12px rgba(74, 52, 30, .08); font-size: 16px; line-height: 1.7; word-break: break-word; }
.msg.user .msg-bubble { border-radius: 18px 4px 18px 18px; background: linear-gradient(135deg, var(--cinnabar-2), var(--cinnabar)); color: #fff; border: none; }
.msg-bubble p { margin: 2px 0; }
.msg-tools { display: flex; align-items: center; justify-content: space-between; margin-top: 6px; }
.msg-tools .ai-tag { margin-left: 0; }
.speak { color: var(--ink-3); display: grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; }
.speak:hover { background: var(--paper-2); color: var(--cinnabar); }
.speak .ic { width: 18px; height: 18px; }
.retry { margin-top: 8px; padding: 6px 14px; font-size: 13px; }

.chat-dock { position: fixed; left: 0; right: 0; bottom: 0; z-index: 20; padding: 8px 12px calc(10px + env(safe-area-inset-bottom)); background: linear-gradient(180deg, transparent, rgba(246, 238, 223, .96) 22%); }
.chat-chips, .chat-input { max-width: 760px; margin: 0 auto; }
.chat-chips .chip { background: rgba(255, 250, 240, .95); }
.chat-input { display: flex; align-items: flex-end; gap: 8px; background: #fffaf0; border: 1.5px solid var(--paper-3); border-radius: 26px; padding: 6px 6px 6px 16px; box-shadow: var(--shadow); transition: border-color .2s; }
.chat-input:focus-within { border-color: var(--gold); }
.chat-input textarea { flex: 1; border: none; outline: none; resize: none; background: transparent; padding: 8px 0; max-height: 120px; font-size: 16px; line-height: 1.5; }
.send { width: 44px; height: 44px; border-radius: 50%; display: grid; place-items: center; color: #fff; background: linear-gradient(135deg, var(--cinnabar-2), var(--cinnabar)); flex-shrink: 0; transition: transform .2s; }
.send:active { transform: scale(.9); }