/* ═══════════════════════════════════════════════════════════════════════════
   高科隨聊 — 設計語言：復古無線電 × 現代極簡
   色調：深夜螢幕綠 + 暗底 + 細線條
   字體：Space Mono（等寬，無線電感）+ Noto Sans TC（中文可讀性）
═══════════════════════════════════════════════════════════════════════════ */

/* ── CSS 變數 ──────────────────────────────────────────────────────────────── */
:root {
  --bg:          #0a0e0f;   /* 近黑底 */
  --bg-2:        #111618;   /* 卡片底 */
  --bg-3:        #181e20;   /* 輸入框底 */
  --green:       #00e5a0;   /* 主色：螢光綠 */
  --green-dim:   #00e5a033; /* 綠色 20% 透明 */
  --green-soft:  #00c98a;   /* 稍暗的綠，hover */
  --text:        #cdd9d6;   /* 主文字 */
  --text-dim:    #5a706a;   /* 次要文字 */
  --border:      #1e2c28;   /* 邊框 */
  --self-bubble: #0f2420;   /* 自己的訊息氣泡底色 */
  --partner-bubble: #181e20;

  --font-mono: "Space Mono", "Courier New", monospace;
  --font-ui:   "Noto Sans TC", sans-serif;

  --radius:  8px;
  --radius-lg: 16px;
  --transition: 0.25s ease;
}

/* ── Reset & Base ──────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow: hidden; /* 整個 app 不滾動，各畫面自己管 */
}

/* ── 畫面切換 ──────────────────────────────────────────────────────────────── */
.screen {
  position: fixed;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
}

.screen.active {
  opacity: 1;
  pointer-events: all;
}

/* ══════════════════════════════════════════════════════════════════════════════
   登入畫面
══════════════════════════════════════════════════════════════════════════════ */
.login-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
  width: 100%;
  max-width: 360px;
  padding: 0 24px;
}

/* 品牌 LOGO */
.brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

/* 三條訊號線動畫（像無線電強度指示器） */
.brand__signal {
  display: flex;
  align-items: flex-end;
  gap: 4px;
  height: 28px;
  margin-bottom: 8px;
}

.brand__signal span {
  display: block;
  width: 4px;
  background: var(--green);
  border-radius: 2px;
  animation: signal-pulse 1.4s ease-in-out infinite;
}

.brand__signal span:nth-child(1) { height: 10px; animation-delay: 0s; }
.brand__signal span:nth-child(2) { height: 20px; animation-delay: 0.2s; }
.brand__signal span:nth-child(3) { height: 14px; animation-delay: 0.4s; }

@keyframes signal-pulse {
  0%, 100% { opacity: 0.3; transform: scaleY(0.6); }
  50%       { opacity: 1;   transform: scaleY(1); }
}

.brand__name {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  color: var(--green);
  letter-spacing: 2px;
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 4px;
  color: var(--text-dim);
}

.login-desc {
  text-align: center;
  color: var(--text-dim);
  font-size: 14px;
  line-height: 2;
}

/* Google 登入按鈕 */
.btn--google {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 24px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 14px;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
  width: 100%;
  justify-content: center;
}

.btn--google:hover {
  border-color: var(--green);
  background: var(--green-dim);
}

.login-note {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 1px;
}

/* ══════════════════════════════════════════════════════════════════════════════
   搜尋畫面：聲納動畫
══════════════════════════════════════════════════════════════════════════════ */
.search-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
}

/* 聲納容器 */
.sonar {
  position: relative;
  width: 120px;
  height: 120px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* 中心點 */
.sonar__core {
  position: relative;
  width: 16px;
  height: 16px;
  background: var(--green);
  border-radius: 50%;
  z-index: 1;
  box-shadow: 0 0 12px var(--green);
}

/* 呼吸燈：中心點本身也脈動 */
.sonar__core::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  background: var(--green);
  opacity: 0.4;
  animation: core-breathe 2s ease-in-out infinite;
}

@keyframes core-breathe {
  0%, 100% { transform: scale(1); opacity: 0.4; }
  50%       { transform: scale(1.5); opacity: 0; }
}

/* 擴散的圓環 */
.sonar__ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid var(--green);
  animation: sonar-expand 2.4s ease-out infinite;
  opacity: 0;
}

.sonar__ring--1 { width: 40px;  height: 40px;  animation-delay: 0s; }
.sonar__ring--2 { width: 80px;  height: 80px;  animation-delay: 0.8s; }
.sonar__ring--3 { width: 120px; height: 120px; animation-delay: 1.6s; }

@keyframes sonar-expand {
  0%   { transform: scale(0.3); opacity: 0.8; }
  100% { transform: scale(1);   opacity: 0; }
}

/* 連接動畫：聲納變快、變亮 */
#screen-searching.connecting .sonar__ring {
  animation-duration: 0.6s;
  border-color: var(--green);
  border-width: 2px;
}

#screen-searching.connecting .sonar__core {
  background: var(--green);
  box-shadow: 0 0 24px var(--green), 0 0 48px var(--green-dim);
}

.search-status {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--green);
  letter-spacing: 1px;
}

/* 閃爍的游標效果 */
.search-status::after {
  content: "_";
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

.search-hint {
  font-size: 13px;
  color: var(--text-dim);
}

/* ══════════════════════════════════════════════════════════════════════════════
   對話畫面
══════════════════════════════════════════════════════════════════════════════ */
#screen-chatting {
  justify-content: flex-start;
}

/* Header */
.chat-header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.chat-header__signal {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chat-header__label {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-dim);
  letter-spacing: 1px;
}

.chat-header__actions {
  display: flex;
  gap: 8px;
}

/* 即時連線指示燈 */
.signal-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-dim);
}

.signal-dot--live {
  background: var(--green);
  box-shadow: 0 0 6px var(--green);
  animation: dot-pulse 2s ease-in-out infinite;
}

@keyframes dot-pulse {
  0%, 100% { box-shadow: 0 0 4px var(--green); }
  50%       { box-shadow: 0 0 10px var(--green); }
}

/* 訊息列表 */
.chat-messages {
  flex: 1;
  width: 100%;
  max-width: 680px;
  align-self: center;
  overflow-y: auto;
  padding: 20px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  scroll-behavior: smooth;
}

/* scrollbar 美化 */
.chat-messages::-webkit-scrollbar { width: 4px; }
.chat-messages::-webkit-scrollbar-track { background: transparent; }
.chat-messages::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

/* 訊息氣泡 */
.msg {
  display: flex;
  animation: msg-in 0.2s ease-out;
}

@keyframes msg-in {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}

.msg--self { justify-content: flex-end; }
.msg--partner { justify-content: flex-start; }

.msg__bubble {
  max-width: 72%;
  padding: 10px 14px;
  border-radius: var(--radius-lg);
  font-size: 14px;
  line-height: 1.6;
  word-break: break-word;
  white-space: pre-wrap;
}

.msg--self .msg__bubble {
  background: var(--self-bubble);
  border: 1px solid #1a3d30;
  color: var(--green);
  border-bottom-right-radius: 4px;
}

.msg--partner .msg__bubble {
  background: var(--partner-bubble);
  border: 1px solid var(--border);
  color: var(--text);
  border-bottom-left-radius: 4px;
}

/* 輸入框區域 */
.chat-input-wrap {
  width: 100%;
  max-width: 680px;
  align-self: center;
  display: flex;
  gap: 8px;
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  background: var(--bg);
}

.chat-input {
  flex: 1;
  background: var(--bg-3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 14px;
  padding: 10px 14px;
  resize: none;
  outline: none;
  transition: border-color var(--transition);
  max-height: 120px;
  overflow-y: auto;
  line-height: 1.5;
}

.chat-input:focus {
  border-color: var(--green);
}

.chat-input::placeholder {
  color: var(--text-dim);
}

/* 送出按鈕 */
.btn-send {
  width: 42px;
  height: 42px;
  flex-shrink: 0;
  background: var(--green-dim);
  border: 1px solid var(--green);
  border-radius: var(--radius);
  color: var(--green);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), box-shadow var(--transition);
  align-self: flex-end;
}

.btn-send:hover {
  background: var(--green);
  color: var(--bg);
  box-shadow: 0 0 12px var(--green-dim);
}

/* ── 共用按鈕 ──────────────────────────────────────────────────────────────── */
.btn-ghost {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 1px;
  padding: 6px 12px;
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition);
}

.btn-ghost:hover {
  border-color: var(--text-dim);
  color: var(--text);
}

.btn-ghost--corner {
  position: absolute;
  top: 20px;
  right: 20px;
}

/* ── Toast 通知 ────────────────────────────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(16px);
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 20px;
  font-size: 13px;
  color: var(--text-dim);
  opacity: 0;
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
  white-space: nowrap;
  z-index: 999;
}

.toast--show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ── 背景細節：細格線（很淡的網格，強化無線電感） ────────────────────────── */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 40px 40px;
  opacity: 0.3;
  pointer-events: none;
  z-index: 0;
}

.screen { z-index: 1; }

/* ── 響應式 ────────────────────────────────────────────────────────────────── */
@media (max-width: 480px) {
  .brand__name { font-size: 22px; }
  .msg__bubble { max-width: 88%; }
  .chat-messages { padding: 16px 12px; }
}

/* ── 無障礙：使用者偏好減少動畫 ───────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .brand__signal span,
  .sonar__ring,
  .sonar__core::after,
  .search-status::after,
  .signal-dot--live,
  .msg { animation: none; }
}

/* ── 打字提示 ──────────────────────────────────────────────────────────────── */
.typing-indicator {
  min-height: 20px;
  padding: 0 16px 4px;
  font-size: 12px;
  color: var(--text-dim);
  font-style: italic;
  max-width: 680px;
  width: 100%;
  align-self: center;
}

/* ── 手機版調整 ────────────────────────────────────────────────────────────── */
@media (max-width: 480px) {
  .chat-header { padding: 10px 14px; }
  .chat-header__label { font-size: 11px; }
  .btn-ghost { padding: 5px 10px; font-size: 10px; }
  .chat-input-wrap { padding: 10px 12px; }
  .chat-input { font-size: 16px; } /* 防止 iOS 自動縮放 */
  .msg__bubble { max-width: 88%; font-size: 15px; }
  .sonar { width: 100px; height: 100px; }
  .sonar__ring--3 { width: 100px; height: 100px; }
}