*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #000000;
  --surface: #121212;
  --surface2: #1a1a1a;
  --surface3: #222222;
  --border: #2a2a2a;
  --border-subtle: #1e1e1e;
  --text: #F8F8F8;
  --text-dim: #6a6a6a;
  --accent-start: #FF4500;
  --accent-end: #FFD700;
  --accent-mid: #FF8C00;
  --danger: #FF4500;
  --danger-hover: #E03E00;
  --glow-orange: rgba(255, 69, 0, 0.15);
  --glow-orange-strong: rgba(255, 69, 0, 0.3);
  --glow-gold: rgba(255, 215, 0, 0.1);
  --msg-self-bg: #1a1a1a;
  --msg-other-bg: #121212;
  --msg-other-glow: rgba(255, 69, 0, 0.06);
  --radius: 2px;
}

@font-face {
  font-family: 'Fallback Mono';
  src: local('JetBrains Mono'), local('Fira Code'), local('Cascadia Code'), local('Consolas'), local('Courier New');
}

body {
  font-family: 'JetBrains Mono', 'Fallback Mono', 'SF Mono', 'Consolas', monospace;
  background: var(--bg);
  color: var(--text);
  height: 100vh;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#app { height: 100vh; }

.screen { display: none; height: 100%; }
.screen.active { display: flex; flex-direction: column; }

/* ===== Scanline overlay ===== */
#app::after {
  content: '';
  position: fixed;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0, 0, 0, 0.03) 2px,
    rgba(0, 0, 0, 0.03) 4px
  );
  pointer-events: none;
  z-index: 9999;
}

/* ===== Auth Screen ===== */
#auth-screen {
  justify-content: center;
  align-items: center;
  padding: 20px;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(255, 69, 0, 0.04) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 50%, rgba(255, 215, 0, 0.02) 0%, transparent 50%),
    var(--bg);
}

#auth-screen h1 {
  font-size: 2.4rem;
  margin-bottom: 24px;
  letter-spacing: 8px;
  text-transform: uppercase;
  color: var(--text);
  text-shadow: 0 0 20px var(--glow-orange-strong), 0 0 40px rgba(255, 69, 0, 0.1);
  position: relative;
}

#auth-screen h1::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent-start), var(--accent-end), transparent);
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  width: 100%;
  max-width: 400px;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--accent-start), var(--accent-end));
}

.tabs { display: flex; gap: 2px; margin-bottom: 20px; }
.tab {
  flex: 1;
  padding: 10px;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-dim);
  cursor: pointer;
  font-size: 0.85rem;
  font-family: inherit;
  text-transform: uppercase;
  letter-spacing: 2px;
  transition: all 0.15s;
}
.tab.active {
  background: var(--surface3);
  color: var(--accent-end);
  border-color: var(--accent-start);
  box-shadow: 0 0 8px rgba(255, 69, 0, 0.15), inset 0 0 8px rgba(255, 69, 0, 0.05);
}

.field { margin-bottom: 16px; }
.field label {
  display: block;
  margin-bottom: 6px;
  font-size: 0.7rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 2px;
}
.field input {
  width: 100%;
  padding: 11px 14px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.9rem;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.field input:focus {
  border-color: var(--accent-start);
  box-shadow: 0 0 6px rgba(255, 69, 0, 0.2);
}
.field input::placeholder { color: #333; }

.input-row { display: flex; gap: 4px; }
.input-row input { flex: 1; }

/* ===== Gradient Border Button Mixin ===== */
.btn-primary {
  position: relative;
  width: 100%;
  padding: 12px;
  background: var(--bg);
  border: none;
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.9rem;
  font-family: inherit;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 3px;
  cursor: pointer;
  overflow: hidden;
  z-index: 1;
}

.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  padding: 2px;
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  z-index: -1;
}

.btn-primary::after {
  content: '';
  position: absolute;
  inset: 2px;
  border-radius: 1px;
  background: var(--bg);
  z-index: -1;
  transition: background 0.2s;
}

.btn-primary:hover::after {
  background: var(--surface2);
}

.btn-primary:hover {
  text-shadow: 0 0 10px var(--glow-orange-strong);
}

.btn-secondary {
  padding: 10px 18px;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-secondary:hover {
  border-color: var(--accent-start);
  color: var(--text);
}

.btn-icon {
  background: none;
  border: 1px solid transparent;
  color: var(--text-dim);
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius);
  transition: all 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
}
.btn-icon:hover {
  color: var(--danger);
  border-color: var(--danger);
  background: rgba(255, 69, 0, 0.08);
}
.btn-icon svg {
  width: 18px;
  height: 18px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.error {
  margin-top: 12px;
  padding: 8px 12px;
  background: rgba(255, 69, 0, 0.08);
  border: 1px solid var(--danger);
  border-radius: var(--radius);
  color: var(--danger);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}
.error.hidden { display: none; }

/* ===== Main Screen ===== */
.main-layout { display: flex; height: 100%; }

/* ===== Sidebar ===== */
.sidebar {
  width: 300px;
  min-width: 300px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: relative;
}

.sidebar::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--accent-start), transparent 30%, transparent 70%, var(--accent-end));
  opacity: 0.3;
}

.sidebar-header {
  padding: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

#my-id-display {
  font-size: 0.75rem;
  color: var(--accent-mid);
  font-family: inherit;
  letter-spacing: 1px;
  opacity: 0.7;
}

.btn-add {
  margin: 10px 14px;
  padding: 10px;
  background: var(--bg);
  border: none;
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.8rem;
  font-family: inherit;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 3px;
  cursor: pointer;
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  overflow: hidden;
  transition: all 0.15s;
}

.btn-add::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  padding: 2px;
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  z-index: -1;
  opacity: 0.5;
  transition: opacity 0.2s;
}

.btn-add::after {
  content: '';
  position: absolute;
  inset: 2px;
  background: var(--bg);
  border-radius: 1px;
  z-index: -1;
}

.btn-add:hover::before { opacity: 1; }
.btn-add:hover { text-shadow: 0 0 10px var(--glow-orange-strong); }

.btn-add svg {
  width: 14px;
  height: 14px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
}

.contact-list {
  list-style: none;
  flex: 1;
  overflow-y: auto;
  padding: 4px;
}

.contact-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.1s;
  gap: 10px;
  border-left: 2px solid transparent;
  position: relative;
}

.contact-item:hover {
  background: var(--surface2);
  border-left-color: var(--accent-start);
}

.contact-item.active {
  background: var(--surface2);
  border-left: 2px solid var(--accent-start);
  box-shadow: inset 4px 0 12px -4px rgba(255, 69, 0, 0.15);
}

.contact-info { flex: 1; min-width: 0; }
.contact-name {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.82rem;
  font-family: inherit;
  letter-spacing: 1px;
  color: var(--text);
}

.contact-name::before {
  content: '@';
  color: var(--text-dim);
  font-weight: 400;
}

.contact-status {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-start);
  box-shadow: 0 0 6px rgba(255, 69, 0, 0.5);
  flex-shrink: 0;
}

.contact-preview {
  display: block;
  font-size: 0.7rem;
  color: var(--text-dim);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin-top: 3px;
  padding-left: 12px;
  letter-spacing: 0.5px;
}

/* ===== Chat Area ===== */
.chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  position: relative;
  background: var(--bg);
}

.chat-placeholder {
  display: flex;
  justify-content: center;
  align-items: center;
  flex: 1;
  color: var(--text-dim);
  font-size: 0.8rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  position: relative;
}

.chat-placeholder::before {
  content: '';
  position: absolute;
  width: 120px;
  height: 120px;
  border: 1px solid var(--border);
  transform: rotate(45deg);
  opacity: 0.2;
}

.chat-view { display: flex; flex-direction: column; height: 100%; }
.chat-view.hidden { display: none; }

.chat-header {
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--surface);
  position: relative;
}

.chat-header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--accent-start), transparent 30%, transparent 70%, var(--accent-end));
  opacity: 0.3;
}

.chat-header-main {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

#chat-contact-name {
  font-weight: 700;
  font-size: 0.9rem;
  font-family: inherit;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--text);
}

.chat-contact-id {
  font-size: 0.65rem;
  color: var(--accent-mid);
  opacity: 0.5;
  letter-spacing: 1px;
}

.chat-header-actions { display: flex; gap: 4px; }

.btn-header {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  padding: 7px;
  transition: all 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.btn-header svg {
  width: 16px;
  height: 16px;
  stroke: var(--text-dim);
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.btn-header:hover {
  border-color: var(--accent-start);
  background: rgba(255, 69, 0, 0.08);
}
.btn-header:hover svg { stroke: var(--accent-start); }

/* ===== BURN ALL Button ===== */
.btn-burn {
  position: relative;
  z-index: 1;
  background: var(--bg) !important;
  border: none !important;
  padding: 7px !important;
  overflow: hidden;
}

.btn-burn::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  padding: 2px;
  background: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  z-index: -1;
  animation: burnPulse 2s ease-in-out infinite;
}

.btn-burn::after {
  content: '';
  position: absolute;
  inset: 2px;
  background: var(--bg);
  border-radius: 1px;
  z-index: -1;
}

.btn-burn:hover {
  box-shadow: 0 0 15px rgba(255, 69, 0, 0.4), 0 0 30px rgba(255, 69, 0, 0.15);
}

.btn-burn:hover svg { stroke: var(--accent-start); }

@keyframes burnPulse {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

/* ===== Messages ===== */
.messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.msg {
  max-width: 70%;
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 0.85rem;
  line-height: 1.5;
  word-break: break-word;
  letter-spacing: 0.3px;
  position: relative;
}

.msg.self {
  align-self: flex-end;
  background: var(--msg-self-bg);
  border: 1px solid var(--border);
  border-right: 2px solid var(--accent-start);
}

.msg.other {
  align-self: flex-start;
  background: var(--msg-other-bg);
  border: 1px solid var(--border-subtle);
  box-shadow: -4px 0 20px -6px rgba(255, 69, 0, 0.12), inset 0 0 20px rgba(255, 69, 0, 0.03);
  border-left: 2px solid rgba(255, 140, 0, 0.3);
}

.msg .meta {
  font-size: 0.65rem;
  color: var(--text-dim);
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.msg .sender {
  color: var(--accent-mid);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.msg .time {
  opacity: 0.5;
}

.msg .time::before {
  content: '[';
}
.msg .time::after {
  content: ']';
}

.msg.system {
  align-self: center;
  background: none;
  color: var(--text-dim);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  max-width: 100%;
  padding: 8px;
  position: relative;
}

.msg.system::before,
.msg.system::after {
  content: '//';
  color: var(--accent-start);
  opacity: 0.4;
  margin: 0 8px;
}

/* ===== Message Form ===== */
.message-form {
  display: flex;
  gap: 4px;
  padding: 14px 16px;
  border-top: 1px solid var(--border);
  background: var(--surface);
  position: relative;
}

.message-form::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent-start), var(--accent-end), transparent);
  opacity: 0.3;
}

.message-form input {
  flex: 1;
  padding: 11px 14px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: inherit;
  font-size: 0.85rem;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.message-form input:focus {
  border-color: var(--accent-start);
  box-shadow: 0 0 6px rgba(255, 69, 0, 0.15);
}

.message-form .btn-primary {
  width: auto;
  padding: 10px 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.message-form .btn-primary svg {
  width: 16px;
  height: 16px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ===== Modals ===== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 100;
  backdrop-filter: blur(4px);
}
.modal-overlay.hidden { display: none; }

.modal {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  width: 100%;
  max-width: 420px;
  position: relative;
  overflow: hidden;
}

.modal::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-start), var(--accent-end));
}

.modal h2 {
  margin-bottom: 6px;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--text);
}

.modal-hint {
  font-size: 0.72rem;
  color: var(--text-dim);
  margin-bottom: 20px;
  letter-spacing: 0.5px;
  line-height: 1.6;
}

.modal-actions { display: flex; gap: 8px; margin-top: 8px; }
.modal-actions .btn-primary { flex: 1; }

/* ===== Scrollbar ===== */
.contact-list::-webkit-scrollbar,
.messages::-webkit-scrollbar { width: 4px; }

.contact-list::-webkit-scrollbar-track,
.messages::-webkit-scrollbar-track { background: var(--bg); }

.contact-list::-webkit-scrollbar-thumb,
.messages::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 0;
}

.contact-list::-webkit-scrollbar-thumb:hover,
.messages::-webkit-scrollbar-thumb:hover { background: var(--accent-start); }

/* ===== Decorative: Corner marks ===== */
.chat-area::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 20px;
  height: 1px;
  background: var(--accent-start);
  opacity: 0.3;
  z-index: 1;
}

.chat-area::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 1px;
  height: 20px;
  background: var(--accent-start);
  opacity: 0.3;
  z-index: 1;
}

/* ===== Responsive ===== */
@media (max-width: 600px) {
  .sidebar { width: 60px; min-width: 60px; }
  .sidebar-header span,
  .btn-add span,
  .contact-preview,
  .contact-name { display: none; }
  .contact-item { justify-content: center; padding: 10px; }
  .contact-status { display: block; }
  .btn-add { padding: 10px; }
}