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

:root {
  --bg: #0f0f0f;
  --bg2: #1a1a1a;
  --bg3: #242424;
  --bg4: #2e2e2e;
  --border: #333;
  --border2: #444;
  --accent: #ff6b2b;
  --accent2: #ffb088;
  --text: #e8e8e8;
  --text2: #999;
  --text3: #666;
  --font-display: 'Syne', sans-serif;
  --font-mono: 'Space Mono', monospace;
  --header-h: 56px;
  --bar-h: 52px;
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-mono);
  overflow: hidden;
}

/* ── HEADER ── */
.header {
  height: var(--header-h);
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 16px;
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
}

.header-left { display: flex; align-items: center; gap: 20px; flex-shrink: 0; }
.header-center { flex: 1; display: flex; justify-content: center; }
.header-right { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }

.logo { display: flex; align-items: center; gap: 8px; }
.logo-icon { color: var(--accent); font-size: 18px; }
.logo-text {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: var(--text);
}
.logo-accent { color: var(--accent); }

.panel-count { display: flex; align-items: baseline; gap: 5px; }
.panel-count #panelCountDisplay {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  min-width: 28px;
}
.panel-count-label { font-size: 9px; color: var(--text3); letter-spacing: 1.5px; }

.layout-presets { display: flex; align-items: center; gap: 4px; }
.presets-label { font-size: 9px; color: var(--text3); letter-spacing: 1.5px; margin-right: 4px; }

.preset-btn {
  background: var(--bg3);
  border: 1px solid var(--border);
  color: var(--text2);
  font-family: var(--font-mono);
  font-size: 10px;
  padding: 4px 8px;
  cursor: pointer;
  transition: all 0.15s;
  letter-spacing: 0.5px;
}
.preset-btn:hover { border-color: var(--accent); color: var(--accent); }
.preset-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.btn-add, .btn-mute-all, .btn-clear {
  display: flex; align-items: center; gap: 5px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  padding: 6px 12px;
  border: 1px solid;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-add { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-add:hover { background: #e55a1f; }
.btn-mute-all { background: transparent; border-color: var(--border2); color: var(--text2); }
.btn-mute-all:hover { border-color: var(--accent2); color: var(--accent2); }
.btn-clear { background: transparent; border-color: var(--border); color: var(--text3); }
.btn-clear:hover { border-color: #e55; color: #e55; }

/* ── QUICK ADD BAR ── */
.quick-add-bar {
  position: fixed;
  top: var(--header-h);
  left: 0; right: 0;
  height: var(--bar-h);
  background: var(--bg3);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 16px;
  z-index: 99;
}

.quick-add-inner { display: flex; align-items: center; gap: 0; flex: 1; max-width: 600px; }
.quick-add-input {
  flex: 1;
  background: var(--bg2);
  border: 1px solid var(--border2);
  border-right: none;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 11px;
  padding: 8px 12px;
  outline: none;
  transition: border-color 0.15s;
}
.quick-add-input:focus { border-color: var(--accent); }
.quick-add-input::placeholder { color: var(--text3); }
.quick-add-btn {
  background: var(--accent);
  border: 1px solid var(--accent);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 1px;
  padding: 8px 16px;
  cursor: pointer;
  transition: background 0.15s;
  white-space: nowrap;
}
.quick-add-btn:hover { background: #e55a1f; }

.quick-add-presets { display: flex; align-items: center; gap: 6px; }
.quick-preset {
  background: var(--bg2);
  border: 1px solid var(--border);
  color: var(--text2);
  font-family: var(--font-mono);
  font-size: 9px;
  padding: 4px 10px;
  cursor: pointer;
  transition: all 0.15s;
  letter-spacing: 0.5px;
  white-space: nowrap;
}
.quick-preset:hover { border-color: var(--accent); color: var(--accent); }

/* ── GRID CONTAINER ── */
.grid-container {
  position: fixed;
  top: calc(var(--header-h) + var(--bar-h));
  left: 0; right: 0; bottom: 0;
  overflow: auto;
  padding: 8px;
  display: grid;
  gap: 6px;
  grid-template-columns: repeat(var(--grid-cols, 1), 1fr);
  grid-auto-rows: minmax(0, 1fr);
  align-content: start;
}

/* ── EMPTY STATE ── */
.empty-state {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: calc(100vh - var(--header-h) - var(--bar-h) - 16px);
  gap: 16px;
  text-align: center;
}
.empty-icon { font-size: 64px; color: var(--border2); line-height: 1; }
.empty-title {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 800;
  color: var(--text3);
  letter-spacing: 4px;
}
.empty-sub { font-size: 12px; color: var(--text3); line-height: 1.8; }
.empty-actions { display: flex; gap: 12px; margin-top: 8px; }
.btn-add-large {
  background: var(--accent);
  border: none;
  color: #fff;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 1px;
  padding: 12px 24px;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-add-large:hover { background: #e55a1f; }
.btn-preset-load {
  background: transparent;
  border: 1px solid var(--border2);
  color: var(--text2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 1px;
  padding: 12px 24px;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-preset-load:hover { border-color: var(--accent); color: var(--accent); }

/* ── PANEL ── */
.panel {
  background: var(--bg2);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-height: 200px;
  position: relative;
  transition: border-color 0.15s;
  animation: panelIn 0.2s ease;
}
.panel:hover { border-color: var(--border2); }
.panel.expanded {
  position: fixed !important;
  top: calc(var(--header-h) + var(--bar-h) + 8px) !important;
  left: 8px !important;
  right: 8px !important;
  bottom: 8px !important;
  z-index: 200;
  border-color: var(--accent) !important;
}

@keyframes panelIn {
  from { opacity: 0; transform: scale(0.96); }
  to   { opacity: 1; transform: scale(1); }
}

.panel-header {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 8px;
  background: var(--bg3);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  height: 36px;
}

.panel-num {
  font-size: 9px;
  color: var(--accent);
  font-weight: 700;
  letter-spacing: 1px;
  min-width: 24px;
}

.panel-url-wrap { display: flex; flex: 1; gap: 0; }
.panel-url-input {
  flex: 1;
  background: var(--bg);
  border: 1px solid var(--border);
  border-right: none;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 10px;
  padding: 4px 8px;
  outline: none;
  min-width: 0;
}
.panel-url-input:focus { border-color: var(--accent); }
.panel-url-input::placeholder { color: var(--text3); }
.panel-load-btn {
  background: var(--bg4);
  border: 1px solid var(--border);
  color: var(--text2);
  font-family: var(--font-mono);
  font-size: 9px;
  padding: 4px 8px;
  cursor: pointer;
  letter-spacing: 1px;
  transition: all 0.15s;
  white-space: nowrap;
}
.panel-load-btn:hover { background: var(--accent); border-color: var(--accent); color: #fff; }

.panel-controls { display: flex; gap: 3px; }
.panel-btn {
  background: var(--bg4);
  border: 1px solid var(--border);
  color: var(--text3);
  font-family: var(--font-mono);
  font-size: 10px;
  width: 24px; height: 24px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  transition: all 0.15s;
  padding: 0;
}
.panel-btn:hover { border-color: var(--accent); color: var(--accent); }
.panel-close-btn:hover { border-color: #e55; color: #e55; }
.panel-mute-btn.muted { background: var(--accent); border-color: var(--accent); color: #fff; }

.panel-body {
  flex: 1;
  position: relative;
  overflow: hidden;
  min-height: 0;
}

.panel-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: var(--bg2);
}
.placeholder-icon { font-size: 32px; color: var(--border2); }
.placeholder-text { font-size: 10px; color: var(--text3); letter-spacing: 1px; }

.panel-iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: none;
  display: none;
}
.panel-iframe.loaded { display: block; }

/* ── SCROLLBAR ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border2); }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .header-center { display: none; }
  .quick-add-presets { display: none; }
  .panel-num { display: none; }
}