:root {
  --font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Pretendard", "Noto Sans KR", "Segoe UI", Roboto, sans-serif;
  --transition-speed: 0.2s;
  --radius-lg: 16px;
  --radius-md: 10px;
  --radius-sm: 6px;
  --radius-pill: 9999px;
}

/* ==========================================================================
   Themes
   ========================================================================== */

/* Classic GagaLive Theme (Default) */
[data-theme="classic"] {
  --bg-page: #e8ecf2;
  --bg-card: #ffffff;
  --bg-header: #2d5594;
  --header-text: #ffffff;
  --header-subtext: #bbd3ff;
  --text-main: #222222;
  --text-muted: #666666;
  --border-color: #d1d8e0;
  
  --my-bubble-bg: #ffec99;
  --my-bubble-text: #333333;
  --my-bubble-border: #ffd43b;
  
  --partner-bubble-bg: #e7f5ff;
  --partner-bubble-text: #1971c2;
  --partner-bubble-border: #a5d8ff;
  
  --system-msg-bg: #f1f3f5;
  --system-msg-text: #495057;
  --system-msg-border: #dee2e6;
  
  --accent-color: #2d5594;
  --accent-hover: #1e3c6d;
  --btn-next-bg: #e64980;
  --btn-next-hover: #d6336c;
  --btn-stop-bg: #868e96;
  --btn-stop-hover: #495057;
  
  --input-bg: #ffffff;
  --input-border: #ced4da;
  --input-focus: #2d5594;
  
  --shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}

/* Modern Dark Theme */
[data-theme="dark"] {
  --bg-page: #0f172a;
  --bg-card: #1e293b;
  --bg-header: #1e293b;
  --header-text: #f8fafc;
  --header-subtext: #94a3b8;
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --border-color: #334155;
  
  --my-bubble-bg: #3b82f6;
  --my-bubble-text: #ffffff;
  --my-bubble-border: transparent;
  
  --partner-bubble-bg: #334155;
  --partner-bubble-text: #f8fafc;
  --partner-bubble-border: transparent;
  
  --system-msg-bg: rgba(51, 65, 85, 0.5);
  --system-msg-text: #cbd5e1;
  --system-msg-border: #334155;
  
  --accent-color: #3b82f6;
  --accent-hover: #2563eb;
  --btn-next-bg: #ec4899;
  --btn-next-hover: #db2777;
  --btn-stop-bg: #475569;
  --btn-stop-hover: #334155;
  
  --input-bg: #0f172a;
  --input-border: #334155;
  --input-focus: #3b82f6;
  
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
}

/* Modern Light Theme */
[data-theme="light"] {
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --bg-header: #ffffff;
  --header-text: #0f172a;
  --header-subtext: #64748b;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  
  --my-bubble-bg: #4f46e5;
  --my-bubble-text: #ffffff;
  --my-bubble-border: transparent;
  
  --partner-bubble-bg: #f1f5f9;
  --partner-bubble-text: #0f172a;
  --partner-bubble-border: transparent;
  
  --system-msg-bg: #f8fafc;
  --system-msg-text: #64748b;
  --system-msg-border: #e2e8f0;
  
  --accent-color: #4f46e5;
  --accent-hover: #4338ca;
  --btn-next-bg: #f43f5e;
  --btn-next-hover: #e11d48;
  --btn-stop-bg: #94a3b8;
  --btn-stop-hover: #64748b;
  
  --input-bg: #f8fafc;
  --input-border: #cbd5e1;
  --input-focus: #4f46e5;
  
  --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05);
}

/* ==========================================================================
   Global Reset & Base
   ========================================================================== */

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  height: 100%;
  width: 100%;
  font-family: var(--font-family);
  background-color: var(--bg-page);
  color: var(--text-main);
  overflow: hidden;
  transition: background-color var(--transition-speed);
}

.app-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100dvh;
  width: 100vw;
  padding: 12px;
}

.chat-container {
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: 780px;
  height: 100%;
  max-height: 900px;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  border: 1px solid var(--border-color);
  overflow: hidden;
  position: relative;
  transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

/* ==========================================================================
   Header
   ========================================================================== */

.chat-header {
  background: var(--bg-header);
  color: var(--header-text);
  padding: 12px 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  user-select: none;
  z-index: 10;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-icon {
  font-size: 1.4rem;
}

.logo-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.logo-badge {
  font-size: 0.68rem;
  padding: 2px 6px;
  background: rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-pill);
  font-weight: 600;
}

.status-stats {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  color: var(--header-subtext);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: #10b981;
  border-radius: 50%;
  display: inline-block;
  animation: pulse-glow 2s infinite;
}

@keyframes pulse-glow {
  0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { box-shadow: 0 0 0 6px rgba(16, 185, 129, 0); }
  100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.header-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.tag-selector {
  background: rgba(255, 255, 255, 0.15);
  color: var(--header-text);
  border: 1px solid rgba(255, 255, 255, 0.3);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  outline: none;
  cursor: pointer;
  transition: background var(--transition-speed);
}

.tag-selector option {
  background: var(--bg-card);
  color: var(--text-main);
}

.icon-btn {
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.25);
  color: var(--header-text);
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.95rem;
  transition: all var(--transition-speed);
}

.icon-btn:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: translateY(-1px);
}

/* ==========================================================================
   Chat Body / Messages Area
   ========================================================================== */

.chat-body {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  scroll-behavior: smooth;
  position: relative;
}

.chat-body::-webkit-scrollbar {
  width: 6px;
}

.chat-body::-webkit-scrollbar-thumb {
  background-color: var(--border-color);
  border-radius: var(--radius-pill);
}

/* Welcome Overlay / Screen */
.welcome-screen {
  margin: auto;
  text-align: center;
  max-width: 440px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.welcome-icon {
  font-size: 3rem;
  margin-bottom: -4px;
}

.welcome-title {
  font-size: 1.35rem;
  font-weight: 700;
}

.welcome-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.btn-start-huge {
  background: var(--accent-color);
  color: #ffffff;
  border: none;
  padding: 12px 28px;
  font-size: 1.05rem;
  font-weight: 700;
  border-radius: var(--radius-pill);
  cursor: pointer;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-speed);
}

.btn-start-huge:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.2);
}

.shortcut-guide {
  margin-top: 10px;
  font-size: 0.78rem;
  color: var(--text-muted);
  background: var(--system-msg-bg);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border-color);
}

.kbd {
  display: inline-block;
  padding: 2px 5px;
  font-size: 0.72rem;
  font-weight: 600;
  line-height: 1;
  color: var(--text-main);
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  box-shadow: 0 1px 1px rgba(0,0,0,0.1);
}

/* Searching State Animation */
.searching-container {
  margin: auto;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.radar-spinner {
  width: 64px;
  height: 64px;
  border: 4px solid var(--border-color);
  border-top-color: var(--accent-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.searching-text {
  font-size: 1.05rem;
  font-weight: 600;
}

.btn-cancel-search {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border-color);
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  font-size: 0.85rem;
  transition: all var(--transition-speed);
}

.btn-cancel-search:hover {
  background: var(--system-msg-bg);
  color: var(--text-main);
}

/* ==========================================================================
   Chat Messages
   ========================================================================== */

.message-row {
  display: flex;
  flex-direction: column;
  width: 100%;
}

.message-row.me {
  align-items: flex-end;
}

.message-row.partner {
  align-items: flex-start;
}

.message-meta {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-bottom: 3px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.message-bubble {
  max-width: 75%;
  padding: 9px 14px;
  border-radius: var(--radius-md);
  font-size: 0.94rem;
  line-height: 1.45;
  word-break: break-word;
  white-space: pre-wrap;
  position: relative;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.message-row.me .message-bubble {
  background-color: var(--my-bubble-bg);
  color: var(--my-bubble-text);
  border: 1px solid var(--my-bubble-border);
  border-bottom-right-radius: 2px;
}

.message-row.partner .message-bubble {
  background-color: var(--partner-bubble-bg);
  color: var(--partner-bubble-text);
  border: 1px solid var(--partner-bubble-border);
  border-bottom-left-radius: 2px;
}

.message-image {
  max-width: 100%;
  max-height: 320px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: block;
  transition: opacity var(--transition-speed);
}

.message-image:hover {
  opacity: 0.95;
}

.message-time {
  font-size: 0.68rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* System Notice Message */
.system-notice {
  text-align: center;
  align-self: center;
  background: var(--system-msg-bg);
  color: var(--system-msg-text);
  border: 1px solid var(--system-msg-border);
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  margin: 6px 0;
  max-width: 90%;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.system-notice.join {
  color: #10b981;
  border-color: rgba(16, 185, 129, 0.3);
}

.system-notice.leave {
  color: #ef4444;
  border-color: rgba(239, 68, 68, 0.3);
}

/* Typing Indicator */
.typing-bar {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--system-msg-bg);
  border-radius: var(--radius-pill);
  width: fit-content;
  font-size: 0.78rem;
  color: var(--text-muted);
  animation: fadeIn 0.3s ease;
}

.typing-bar.active {
  display: flex;
}

.typing-dots {
  display: flex;
  gap: 4px;
}

.typing-dot {
  width: 5px;
  height: 5px;
  background-color: var(--text-muted);
  border-radius: 50%;
  animation: bounce 1.4s infinite ease-in-out both;
}

.typing-dot:nth-child(1) { animation-delay: -0.32s; }
.typing-dot:nth-child(2) { animation-delay: -0.16s; }

@keyframes bounce {
  0%, 80%, 100% { transform: scale(0); }
  40% { transform: scale(1); }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ==========================================================================
   Bottom Controls & Input
   ========================================================================== */

.chat-footer {
  border-top: 1px solid var(--border-color);
  background: var(--bg-card);
  padding: 10px 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 10;
}

.control-btn-bar {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
}

.btn-ctrl {
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-speed);
}

.btn-ctrl:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-ctrl.btn-next {
  background: var(--btn-next-bg);
  color: #ffffff;
}

.btn-ctrl.btn-next:not(:disabled):hover {
  background: var(--btn-next-hover);
  transform: translateY(-1px);
}

.btn-ctrl.btn-stop {
  background: var(--btn-stop-bg);
  color: #ffffff;
}

.btn-ctrl.btn-stop:not(:disabled):hover {
  background: var(--btn-stop-hover);
}

.btn-ctrl.btn-util {
  background: var(--system-msg-bg);
  color: var(--text-main);
  border: 1px solid var(--border-color);
}

.btn-ctrl.btn-util:not(:disabled):hover {
  background: var(--border-color);
}

.input-area {
  display: flex;
  gap: 8px;
  align-items: flex-end;
}

.input-box-wrapper {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
}

.chat-textarea {
  width: 100%;
  min-height: 44px;
  max-height: 120px;
  padding: 10px 42px 10px 14px;
  border-radius: var(--radius-md);
  border: 1px solid var(--input-border);
  background: var(--input-bg);
  color: var(--text-main);
  font-family: inherit;
  font-size: 0.94rem;
  resize: none;
  outline: none;
  line-height: 1.4;
  transition: border-color var(--transition-speed);
}

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

.chat-textarea:disabled {
  background: var(--system-msg-bg);
  cursor: not-allowed;
}

.btn-attach-img {
  position: absolute;
  right: 8px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 6px;
  font-size: 1.15rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color var(--transition-speed);
}

.btn-attach-img:hover {
  color: var(--accent-color);
}

.btn-send {
  background: var(--accent-color);
  color: #ffffff;
  border: none;
  padding: 0 18px;
  height: 44px;
  border-radius: var(--radius-md);
  font-weight: 700;
  font-size: 0.94rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: all var(--transition-speed);
  flex-shrink: 0;
}

.btn-send:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-send:not(:disabled):hover {
  background: var(--accent-hover);
}

/* Image Zoom Modal */
.image-modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.85);
  z-index: 9999;
  justify-content: center;
  align-items: center;
  cursor: zoom-out;
}

.image-modal.active {
  display: flex;
}

.image-modal-content {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-sm);
  box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */

@media (max-width: 600px) {
  .app-wrapper {
    padding: 0;
  }
  
  .chat-container {
    height: 100dvh;
    max-height: 100dvh;
    border-radius: 0;
    border: none;
  }

  .chat-header {
    padding: 10px 12px;
  }

  .logo-title {
    font-size: 1rem;
  }

  .status-stats {
    font-size: 0.72rem;
    gap: 6px;
  }

  .message-bubble {
    max-width: 86%;
    font-size: 0.9rem;
  }

  .control-btn-bar {
    gap: 6px;
  }

  .btn-ctrl {
    padding: 5px 10px;
    font-size: 0.78rem;
  }

  .btn-send {
    padding: 0 14px;
    font-size: 0.88rem;
  }
}