/* =========================================================
   THEME VARIABLES
========================================================= */
:root {
  --bg-app:          #f0f2f5;
  --bg-header:       #ffffff;
  --bg-bubble-out:   #dcf8c6;
  --bg-bubble-in:    #ffffff;
  --bg-input:        #ffffff;
  --bg-quote:        #f8f9fa;
  --border-subtle:   #e4e6eb;
  --text-main:       #111b21;
  --text-sub:        #667781;
  --text-time:       #8696a0;
  --accent:          #007af5;
  --accent-hover:    #0064c7;
  --danger:          #ea3943;
  --shadow-sm:       0 1px 3px rgba(0,0,0,0.08);
  --shadow-md:       0 4px 12px rgba(0,0,0,0.12);
  --radius-bubble:   12px;
  --radius-sm:       8px;
  --font-sans:       -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  
  /* Markdown & Code styling variables */
  --bg-code:         rgba(0, 0, 0, 0.05);
  --text-code:       #e01e5a;
}

[data-theme="dark"] {
  --bg-app:          #111111;
  --bg-header:       #1a1a1a;
  --bg-bubble-out:   #005c4b;
  --bg-bubble-in:    #2d2d2d;
  --bg-input:        #2a2a2a;
  --bg-quote:        #262626;
  --border-subtle:   #3a3a3a;
  --text-main:       #e4e6eb;
  --text-sub:        #a0a0a0;
  --text-time:       #8c8c8c;
  --shadow-sm:       0 1px 3px rgba(0,0,0,0.4);
  --shadow-md:       0 4px 12px rgba(0,0,0,0.5);
  
  /* Markdown dark theme adjustments */
  --bg-code:         rgba(255, 255, 255, 0.1);
  --text-code:       #ff7b9f;
}

/* =========================================================
   RESET & BASE
========================================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  overflow: hidden;
  font-family: var(--font-sans);
  background: var(--bg-app);
  color: var(--text-main);
  transition: background-color 0.3s, color 0.3s;
}

.hidden { display: none !important; }

/* =========================================================
   LOGIN SCREEN
========================================================= */
#login {
  position: fixed; inset: 0;
  display: flex; align-items: center; justify-content: center;
  padding: 20px;
  background: var(--bg-app);
  overflow-y: auto;
}

.login-card {
  background: var(--bg-header);
  border-radius: 16px;
  padding: 32px 24px;
  width: 100%; max-width: 420px;
  box-shadow: var(--shadow-md);
  margin: auto;
}

.login-card h1 { text-align: center; margin-bottom: 24px; color: var(--accent); }

.form-group { margin-bottom: 14px; }
.form-group label { display: block; font-size: 0.8rem; font-weight: 600; color: var(--text-sub); margin-bottom: 4px; }

.form-input {
  width: 100%; padding: 12px 14px;
  background: var(--bg-app); color: var(--text-main);
  border: 1.5px solid var(--border-subtle); border-radius: 10px;
  font-size: 0.95rem; outline: none; transition: border-color 0.2s;
}
.form-input:focus { border-color: var(--accent); }

.btn-primary {
  width: 100%; padding: 13px;
  background: var(--accent); color: #fff;
  border: none; border-radius: 10px; font-weight: 600; cursor: pointer;
  margin-top: 8px; font-size: 1rem;
}
.btn-primary:hover { background: var(--accent-hover); }

/* PWA Install Button */
.btn-outline-pwa {
  width: 100%; padding: 10px;
  background: transparent; color: var(--accent);
  border: 1.5px solid var(--accent); border-radius: 10px; font-weight: 600; cursor: pointer;
  margin-top: 12px; font-size: 0.88rem; transition: background 0.2s, color 0.2s;
}
.btn-outline-pwa:hover { background: var(--accent); color: #fff; }

.login-note {
  margin-top: 16px; font-size: 0.75rem; color: var(--text-sub);
  line-height: 1.5; text-align: center;
}

/* =========================================================
   CHAT LAYOUT
========================================================= */
#chat {
  position: fixed; inset: 0;
  display: flex; flex-direction: column;
}

/* Header */
.chat-header {
  flex-shrink: 0; display: flex; align-items: center; gap: 8px;
  padding: 12px 16px; background: var(--bg-header);
  border-bottom: 1px solid var(--border-subtle); z-index: 10;
  box-shadow: var(--shadow-sm);
}
.header-title { flex: 1; font-weight: 600; font-size: 1rem; }
.header-sub { font-size: 0.72rem; color: var(--text-sub); }

.icon-btn {
  background: transparent; border: none; cursor: pointer; padding: 8px;
  border-radius: 50%; color: var(--text-sub); transition: background 0.2s;
  display: flex; align-items: center; justify-content: center;
}
.icon-btn:hover { background: var(--border-subtle); }

/* Reply Preview Bar */
#reply-bar {
  flex-shrink: 0; display: none; align-items: center; gap: 10px;
  padding: 8px 16px; background: var(--bg-quote);
  border-top: 1px solid var(--border-subtle); z-index: 9;
}
.quote-prev {
  flex: 1; padding: 4px; border-left: 3px solid var(--accent);
  background: var(--bg-app); border-radius: 6px;
  font-size: 0.8rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.quote-cancel { cursor: pointer; padding: 4px 12px; border-radius: 12px; background: var(--border-subtle); color: var(--text-main); font-size: 0.8rem; }

/* Messages Area */
#msgs {
  position: relative; /* Enables accurate offset calculation scrollings */
  flex: 1; overflow-y: auto; padding: 16px 10px 8px;
  display: flex; flex-direction: column; gap: 4px;
  scroll-behavior: smooth;
  background-image: radial-gradient(var(--border-subtle) 1px, transparent 1px);
  background-size: 20px 20px; opacity: 1;
}
#msgs::-webkit-scrollbar { width: 5px; }
#msgs::-webkit-scrollbar-thumb { background: var(--text-sub); border-radius: 10px; }

/* CSS Boundary Fixes */
.msg-row { 
  display: flex; 
  flex-direction: column; 
  max-width: 85%; 
  align-self: flex-start;
  min-width: 0; 
  transition: background-color 0.25s ease-out, border-radius 0.25s ease-out;
}
.msg-row.mine { align-self: flex-end; align-items: flex-end; }

/* Highlight context targeting actively referenced/replied message container block */
.msg-row.reply-focused .bubble {
  box-shadow: 0 0 0 3px var(--accent), var(--shadow-md) !important;
  background-color: #eef7ff !important;
}
.msg-row.mine.reply-focused .bubble {
  background-color: #e1f5fe !important;
}
[data-theme="dark"] .msg-row.reply-focused .bubble {
  background-color: #1a2536 !important;
}
[data-theme="dark"] .msg-row.mine.reply-focused .bubble {
  background-color: #0c4238 !important;
}

/* Quote inside message */
.msg-quote {
  display: inline-block; max-width: 100%; margin-bottom: 6px;
  padding: 8px 10px; background: var(--bg-quote); border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm); font-size: 0.78rem; color: var(--text-sub);
  overflow: hidden; white-space: nowrap; text-overflow: ellipsis; cursor: pointer;
}
.msg-quote:hover { background: var(--border-subtle); }

/* Bubble styling (Enables full-area reply context) */
.bubble {
  padding: 10px 14px; border-radius: var(--radius-bubble);
  box-shadow: var(--shadow-sm); position: relative; word-break: break-word;
  background: var(--bg-bubble-in);
  max-width: 100%;
  overflow: hidden; 
  cursor: pointer;
  transition: background-color 0.25s ease, box-shadow 0.25s ease;
}
.msg-row.mine .bubble { background: var(--bg-bubble-out); border-bottom-right-radius: 4px; }
.msg-row.yours .bubble { border-bottom-left-radius: 4px; }

.msg-header { font-size: 0.72rem; color: var(--text-sub); margin-bottom: 3px; display: flex; align-items: baseline; gap: 6px; }

/* Adaptive user colors */
.msg-nick {
  font-weight: 600;
  color: hsl(var(--hue, 0), 65%, 42%);
}
[data-theme="dark"] .msg-nick {
  color: hsl(var(--hue, 0), 65%, 78%);
}

/* Msg Text Container styling + List spacing limits */
.msg-text { 
  font-size: 0.92rem; 
  line-height: 1.45; 
  white-space: normal; /* FIX: Prevents literal HTML newlines from leaving layout gaps */
  word-break: break-word;
}
.msg-text.plaintext {
  white-space: pre-wrap; /* Kept for fallback simple message spacing spacing layout rules */
}
.msg-text a { color: var(--accent); text-decoration: underline; }
.msg-text p { margin-bottom: 6px; }
.msg-text p:last-child { margin-bottom: 0; }
.msg-text ul, .msg-text ol { padding-left: 20px; margin: 6px 0; }
.msg-text li { margin-bottom: 3px; }
.msg-text code {
  font-family: SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 0.85rem;
  background: var(--bg-code);
  color: var(--text-code);
  padding: 2px 5px;
  border-radius: 4px;
}

/* Dynamic Table Formatting Rules */
.msg-text table {
  border-collapse: collapse;
  width: 100%;
  margin: 12px 0;
  font-size: 0.82rem;
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.msg-text th, .msg-text td {
  border: 1px solid var(--border-subtle);
  padding: 8px 12px;
  text-align: left;
}
.msg-text th {
  background-color: var(--bg-quote);
  color: var(--text-main);
  font-weight: 600;
}
.msg-text tr:nth-child(even) {
  background-color: rgba(0, 0, 0, 0.02);
}
[data-theme="dark"] .msg-text tr:nth-child(even) {
  background-color: rgba(255, 255, 255, 0.03);
}

/* Beautiful Blockquote Indent Spacers */
.msg-text blockquote {
  border-inline-start: 4px solid var(--accent);
  background: var(--bg-quote);
  padding: 8px 14px;
  margin: 10px 0;
  border-radius: 4px;
  color: var(--text-sub);
}
.msg-text blockquote p {
  margin-bottom: 0 !important;
}

/* =========================================================
   PRISM TOOLBAR PLUGIN CUSTOM STYLE OVERRIDES
========================================================= */
.msg-text .code-toolbar {
  position: relative;
  margin: 8px 0;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column-reverse; /* Places toolbar beautifully above pre elements */
  background: #2d2d2d;
  cursor: default;
}

/* Overrides Prism relative toolbar hover states to make it a static dark header */
.msg-text .code-toolbar > .toolbar {
  position: static !important;
  opacity: 1 !important;
  display: flex !important;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  background: #1e1e1e !important;
  padding: 6px 12px !important;
  box-sizing: border-box;
  border-bottom: 1px solid #2d2d2d;
}

.msg-text .code-toolbar .toolbar-item {
  display: inline-block !important;
}

/* Language title labels inside toolbar */
.msg-text .code-toolbar .toolbar-item span {
  color: #a0a0a0 !important;
  font-family: var(--font-sans) !important;
  font-size: 0.72rem !important;
  font-weight: 600 !important;
  text-transform: uppercase;
}

/* Official Prism Copy button elements */
.msg-text .code-toolbar .toolbar-item button {
  background: transparent !important;
  border: 1px solid #444 !important;
  color: #a0a0a0 !important;
  padding: 2px 8px !important;
  border-radius: 4px !important;
  font-family: var(--font-sans) !important;
  font-size: 0.68rem !important;
  cursor: pointer !important;
  transition: background 0.15s, color 0.15s, border-color 0.15s !important;
  outline: none !important;
  box-shadow: none !important;
}

.msg-text .code-toolbar .toolbar-item button:hover {
  background: var(--accent) !important;
  color: #fff !important;
  border-color: var(--accent) !important;
}

/* Native Copy Success Feedback with Animation */
@keyframes popSuccess {
  0% { transform: scale(1); }
  50% { transform: scale(1.08); }
  100% { transform: scale(1); }
}
.msg-text .code-toolbar .toolbar-item button[data-copy-state="copy-success"] {
  background: #2e7d32 !important; /* Green pop color for copying confirmation */
  color: #fff !important;
  border-color: #2e7d32 !important;
  animation: popSuccess 0.3s ease-out;
}

/* Force standard Prism container scrolling internally within bubbles */
.msg-text pre {
  margin: 0 !important;
  padding: 12px !important;
  background: #2d2d2d !important;
  color: #f8f8f2 !important;
  overflow-x: auto !important;
  max-width: 100% !important;
  border-radius: 0 !important;
  border: none !important;
  box-shadow: none !important;
}
.msg-text pre code {
  background: transparent !important;
  color: inherit !important;
  padding: 0 !important;
  border-radius: 0 !important;
  white-space: pre !important;
  font-family: SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace !important;
  font-size: 0.85rem !important;
}

/* Custom code block horizontal scrollbars for accessibility */
.msg-text pre::-webkit-scrollbar {
  height: 6px;
}
.msg-text pre::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.25);
  border-radius: 4px;
}
.msg-text pre::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.45);
}

/* LaTeX Custom Math styling overrides */
.msg-text .katex-display { margin: 6px 0; overflow-x: auto; overflow-y: hidden; }
.msg-text .katex { font-size: 1.05em; }

.msg-meta { display: flex; justify-content: flex-end; align-items: center; gap: 5px; margin-top: 3px; }
.msg-time { font-size: 0.68rem; color: var(--text-time); }

/* Date Separator */
.date-sep { align-self: center; margin: 16px 0 8px; background: var(--bg-quote); padding: 4px 12px; border-radius: 12px; font-size: 0.72rem; color: var(--text-sub); }

/* Unread Bookmark Separator */
.unread-sep {
  align-self: center;
  margin: 16px 0 8px;
  background: #ffebeb;
  border: 1px solid #ffccd2;
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 0.72rem;
  color: var(--danger);
  font-weight: bold;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  transition: opacity 0.3s ease, margin 0.3s ease, padding 0.3s ease, height 0.3s ease;
}
[data-theme="dark"] .unread-sep {
  background: #2d1a1a;
  border-color: #5c2424;
  color: #ff8080;
}

/* Input Bar */
.input-area {
  flex-shrink: 0; padding: 10px 12px; padding-bottom: max(10px, env(safe-area-inset-bottom));
  background: var(--bg-header); border-top: 1px solid var(--border-subtle);
  display: flex; align-items: flex-end; gap: 8px;
}
#msg-input {
  flex: 1; min-height: 40px; max-height: 140px; padding: 10px 14px;
  background: var(--bg-app); color: var(--text-main); border: 1px solid var(--border-subtle);
  border-radius: 20px; resize: none; outline: none; font-family: inherit; font-size: 0.95rem;
  line-height: 1.4;
  overflow-y: hidden; /* FIX: Prevents permanently grayed-out scrollbars in Windows */
}
#msg-input:focus { border-color: var(--accent); }
.btn-send {
  width: 42px; height: 42px; border-radius: 50%; border: none;
  background: var(--accent); color: #fff; cursor: pointer; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-sm);
}
.btn-send:hover { background: var(--accent-hover); }
.btn-send:disabled { background: var(--border-subtle); cursor: default; box-shadow: none; }

/* Scroll-to-bottom FAB */
.fab-scroll {
  position: absolute;
  bottom: 80px;
  right: 16px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--bg-header);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  font-size: 1.2rem;
  box-shadow: var(--shadow-md);
  cursor: pointer;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity 0.2s, transform 0.2s, background-color 0.2s;
}
.fab-scroll:hover {
  background: var(--bg-app);
}
.fab-scroll.visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

/* Pulsing Notification Badge Blip on FAB scroll button */
.fab-scroll.has-unread::after {
  content: '';
  position: absolute;
  top: 3px;
  right: 3px;
  width: 10px;
  height: 10px;
  background-color: var(--danger);
  border-radius: 50%;
  border: 1.5px solid var(--bg-header);
  box-shadow: 0 0 6px var(--danger);
  animation: blipPulse 1.2s infinite ease-in-out;
}
@keyframes blipPulse {
  0% { transform: scale(0.9); opacity: 0.8; }
  50% { transform: scale(1.25); opacity: 1; }
  100% { transform: scale(0.9); opacity: 0.8; }
}

/* Loading / Error */
.system-msg { text-align: center; color: var(--text-sub); font-size: 0.78rem; padding: 12px 0; }
.retry-btn { margin-top: 4px; background: var(--danger); color: #fff; border: none; padding: 4px 10px; border-radius: 6px; font-size: 0.75rem; cursor: pointer; }