:root {
  color-scheme: dark;
  --bg: #0f1720;
  --drawer-bg: #17222f;
  --drawer-bg-2: #1c2a3a;
  --border: #263443;
  --text: #e7edf3;
  --muted: #8695a7;
  --accent: #22d3ee;
  --accent-dim: rgba(34, 211, 238, 0.12);
  --drawer-w: 280px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  overflow: hidden;
}

.app {
  display: flex;
  height: 100vh;
  position: relative;
  isolation: isolate;
}

/* ---------- Drawer ---------- */

.drawer {
  position: relative;
  width: var(--drawer-w);
  flex-shrink: 0;
  overflow: hidden;
  background: var(--drawer-bg);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-height: 0;
  transition: width 0.22s ease, transform 0.22s ease;
  z-index: 30;
}

.app.collapsed .drawer {
  width: 0;
  border-right-color: transparent;
}

.drawer-inner {
  width: var(--drawer-w);
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
  background: var(--drawer-bg);
}

.drawer-header {
  padding: 1.25rem 1.1rem 0.9rem;
  flex-shrink: 0;
}

.drawer-header h1 {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  margin: 0 0 0.15rem;
  color: var(--text);
}

.drawer-header .subtitle {
  font-size: 0.75rem;
  color: var(--muted);
}

.search-wrap {
  padding: 0 1.1rem 0.9rem;
  flex-shrink: 0;
}

.search-wrap input {
  width: 100%;
  background: var(--drawer-bg-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.55rem 0.75rem;
  color: var(--text);
  font-size: 0.85rem;
  outline: none;
}

.search-wrap input::placeholder { color: var(--muted); }

.search-wrap input:focus {
  border-color: var(--accent);
}

.site-list {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 0.25rem 0 1rem;
  background: var(--drawer-bg);
}

.site-list::-webkit-scrollbar { width: 8px; }
.site-list::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}

.site-item {
  display: block;
  width: 100%;
  text-align: left;
  background: var(--drawer-bg);
  border: none;
  border-left: 3px solid transparent;
  color: var(--muted);
  font-size: 0.82rem;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  padding: 0.7rem 1.05rem 0.7rem 1rem;
  cursor: pointer;
  font-family: inherit;
}

.site-item[hidden] {
  display: none;
}

.site-item:hover {
  color: var(--text);
  background: var(--drawer-bg-2);
}

.site-item.active {
  color: var(--text);
  font-weight: 600;
  background: var(--accent-dim);
  border-left-color: var(--accent);
}

.empty-msg, .status {
  padding: 0.9rem 1.1rem;
  color: var(--muted);
  font-size: 0.82rem;
  background: var(--drawer-bg);
}

/* ---------- Toggle button ---------- */

.toggle-btn {
  position: absolute;
  top: 50%;
  left: var(--drawer-w);
  transform: translateY(-50%);
  width: 36px;
  height: 60px;
  border-radius: 0 8px 8px 0;
  border: 1px solid var(--border);
  background: var(--drawer-bg-2);
  color: var(--muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 31;
  transition: left 0.22s ease, opacity 0.15s ease;
  font-size: 1.1rem;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.45);
  opacity: 1;
}

.app.collapsed .toggle-btn { opacity: 0.5; }

.toggle-btn:hover,
.toggle-btn:focus-visible {
  color: var(--text);
  opacity: 1;
}

.toggle-btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.app.collapsed .toggle-btn { left: 0; }

/* ---------- Backdrop (mobile) ---------- */

.backdrop {
  display: none;
}

/* ---------- Main content ---------- */

.content {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  position: relative;
  z-index: 0;
}

.content-header {
  position: relative;
  z-index: 5;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.85rem 1.25rem;
  border-bottom: 1px solid var(--border);
  background: var(--drawer-bg);
}

#current-domain {
  font-size: 0.9rem;
  color: var(--text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

#open-new-tab {
  flex-shrink: 0;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.82rem;
  white-space: nowrap;
}

#open-new-tab:hover { text-decoration: underline; }

.iframe-wrap {
  flex: 1;
  position: relative;
  z-index: 1;
  min-height: 0;
  background: #0b1218;
}

#site-frame {
  width: 100%;
  height: 100%;
  border: none;
  display: none;
}

.placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
  color: var(--muted);
  font-size: 0.95rem;
}

/* ---------- Mobile overlay behavior ---------- */

@media (max-width: 700px) {
  .drawer {
    position: fixed;
    top: 0;
    left: 0;
    height: 100%;
    transform: translateX(0);
    box-shadow: 0 0 24px rgba(0, 0, 0, 0.4);
  }

  .app.collapsed .drawer {
    width: var(--drawer-w);
    transform: translateX(-100%);
    border-right-color: var(--border);
  }

  .toggle-btn {
    left: var(--drawer-w);
  }

  .app.collapsed .toggle-btn {
    left: 0;
  }

  .app:not(.collapsed) .backdrop {
    display: block;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    z-index: 20;
  }
}