/* App frame: a fixed top bar and one scrolling screen underneath. */
body {
  display: flex;
  flex-direction: column;
}

.topbar {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  flex-wrap: wrap;
  padding: var(--sp-2) var(--sp-4);
  background: var(--bg-panel);
  border-block-end: 1px solid var(--border);
  position: sticky;
  inset-block-start: 0;
  z-index: 20;
}

.logo {
  font-weight: 700;
  font-size: var(--fs-lg);
  text-decoration: none;
  color: var(--text);
  white-space: nowrap;
}
.logo .logo-dot {
  color: var(--accent);
}

.topnav {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  flex-wrap: wrap;
  flex: 1;
}

.topbar-tools {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  margin-inline-start: auto;
}

.screen {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
}

/* Three column workspace. In RTL the first column lands on the right. */
.workspace {
  --w-task: 340px;
  --w-ref: 320px;
  display: grid;
  grid-template-columns: var(--w-task) 6px minmax(320px, 1fr) 6px var(--w-ref);
  flex: 1;
  min-height: 0;
  background: var(--bg);
}

.panel {
  min-width: 0;
  min-height: 0;
  overflow: auto;
  background: var(--bg-panel);
  display: flex;
  flex-direction: column;
}

.panel-work {
  background: var(--bg);
}

.resizer {
  background: var(--bg);
  border-inline: 1px solid var(--border);
  cursor: col-resize;
  touch-action: none;
}
.resizer:hover,
.resizer[data-dragging='true'] {
  background: var(--accent-soft);
}

.panel-head {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-3);
  border-block-end: 1px solid var(--border);
  background: var(--bg-panel);
  position: sticky;
  inset-block-start: 0;
  z-index: 2;
}
.panel-head h2 {
  margin: 0;
  font-size: var(--fs-sm);
  color: var(--text-soft);
  letter-spacing: 0.02em;
}
.panel-body {
  padding: var(--sp-3);
  flex: 1;
}

.workspace-tabs {
  display: none;
}

/* Content screens that are not the three column workspace. */
.page {
  padding: var(--sp-5) var(--sp-4);
  max-width: 1100px;
  margin-inline: auto;
  width: 100%;
}

@media (max-width: 900px) {
  .workspace {
    display: block;
  }
  .resizer {
    display: none;
  }
  .panel {
    display: none;
    overflow: visible;
  }
  .workspace[data-tab='task'] .panel-task,
  .workspace[data-tab='work'] .panel-work,
  .workspace[data-tab='ref'] .panel-ref {
    display: flex;
  }
  .workspace-tabs {
    display: flex;
    gap: var(--sp-1);
    padding: var(--sp-2);
    background: var(--bg-panel);
    border-block-end: 1px solid var(--border);
    position: sticky;
    inset-block-start: 0;
    z-index: 10;
  }
  .workspace-tabs button {
    flex: 1;
  }
  .topnav {
    order: 3;
    /* Its own full width row, scrolled sideways, so the tools never clip it. */
    flex: 0 0 100%;
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-block-start: var(--sp-1);
  }
  .topbar {
    padding: var(--sp-2);
  }
}