/* Copyright (c) 2026 Eleftherios Notas and The XIOM Authors
   SPDX-License-Identifier: MIT OR Apache-2.0
   Algorithm Lab screen: split player, controls, and responsive rules. */

.lab-screen {
  height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--void);
  color: var(--hi);
  font-family: var(--sans);
  overflow: hidden;
}

.lab-screen .header {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  min-height: 52px;
}

.lab-screen .header .lesson-header-title {
  font-weight: 600;
  font-size: 14px;
  color: var(--hi);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.lab-screen .header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
}

.lab-screen .nav-btn.active {
  border-color: var(--indigo);
  color: var(--indigo);
}

.lab-layout {
  flex: 1;
  display: flex;
  min-height: 0;
}

.lab-list {
  width: 252px;
  min-width: 252px;
  overflow-y: auto;
  border-right: 1px solid var(--border);
  padding: 8px;
  background: var(--panel);
}

.lab-category {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 6px 4px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--low);
}

.lab-entry {
  display: block;
  width: 100%;
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  padding: 8px 10px;
  margin-bottom: 2px;
  color: var(--hi);
  cursor: pointer;
  font-family: var(--sans);
}

.lab-entry:hover {
  background: var(--panel-2);
  border-color: var(--border);
}

.lab-entry:focus-visible {
  outline: 2px solid var(--indigo);
  outline-offset: 1px;
}

.lab-entry.active {
  background: var(--indigo-soft);
  border-color: var(--indigo);
}

.lab-entry-title {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 2px;
}

.lab-entry-blurb {
  display: block;
  font-size: 12px;
  line-height: 1.4;
  color: var(--mid);
}

.lab-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
}

.lab-panes {
  flex: 1;
  display: flex;
  gap: 10px;
  padding: 10px;
  min-height: 0;
}

.lab-pane {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--panel);
  overflow: hidden;
}

.lab-pane-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-bottom: 1px solid var(--border-soft);
  background: var(--panel-2);
}

.lab-preset {
  background: var(--panel);
  color: var(--hi);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 4px 6px;
  font-size: 12px;
  max-width: 200px;
}

.lab-counters {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--mid);
  white-space: nowrap;
}

.lab-pane-body {
  flex: 1;
  display: flex;
  min-height: 0;
}

.lab-code-pane {
  width: 46%;
  min-width: 240px;
  max-width: 560px;
  display: flex;
  flex-direction: column;
  min-height: 0;
  border-right: 1px solid var(--border-soft);
  background: var(--void);
}

.lab-code-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 5px 8px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--low);
  border-bottom: 1px solid var(--border-soft);
}

.lab-code-toggle {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--mid);
  border-radius: var(--radius-sm);
  font-size: 11px;
  padding: 3px 8px;
  cursor: pointer;
}

.lab-code-toggle:hover {
  color: var(--hi);
  border-color: var(--border-hover);
}

.lab-code-pane.collapsed .lab-editor {
  display: none;
}

.lab-code-pane.collapsed .lab-code-head {
  padding: 5px 6px;
  border-bottom: 0;
}

.lab-code-pane.collapsed .lab-code-head > span {
  display: none;
}

.lab-code-pane.collapsed {
  width: auto;
  min-width: 0;
  max-width: none;
  flex: 0 0 auto;
  border-right: 0;
}

.lab-editor {
  flex: 1;
  min-height: 0;
}

.lab-code-edit {
  position: relative;
  width: 100%;
  height: 100%;
}

.lab-code-highlight {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.lab-code-highlight-line {
  position: absolute;
  left: 0;
  right: 0;
  background: rgba(92, 107, 255, 0.22);
}

.lab-code-textarea {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  resize: none;
  border: 0;
  outline: none;
  background: transparent;
  color: var(--hi);
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.5;
  padding: 10px;
  white-space: pre;
  overflow: auto;
  z-index: 1;
}

.lab-view {
  position: relative;
  flex: 1;
  min-width: 0;
  min-height: 0;
  display: flex;
  flex-direction: column;
}

.lab-canvas {
  flex: 1;
  min-height: 0;
  display: block;
}

.lab-status {
  min-height: 30px;
  padding: 6px 10px;
  border-top: 1px solid var(--border-soft);
  font-size: 12px;
  color: var(--mid);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.lab-status.ok { color: var(--green); }
.lab-status.err { color: var(--error); }

.lab-controls {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-top: 1px solid var(--border);
  background: var(--panel);
  flex-wrap: wrap;
}

.lab-btn {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--hi);
  border-radius: var(--radius-sm);
  padding: 5px 11px;
  cursor: pointer;
  font-size: 14px;
  line-height: 1.2;
}

.lab-btn:hover {
  border-color: var(--border-hover);
}

.lab-btn:focus-visible,
.lab-code-toggle:focus-visible,
.lab-preset:focus-visible,
.lab-scrub:focus-visible {
  outline: 2px solid var(--indigo);
  outline-offset: 2px;
}

.lab-speed {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--mid);
  white-space: nowrap;
}

.lab-speed input[type="range"] {
  width: 110px;
  accent-color: var(--indigo);
}

.lab-speed-label {
  font-family: var(--mono);
  font-size: 11px;
  min-width: 34px;
}

.lab-scrub {
  flex: 1;
  min-width: 120px;
  accent-color: var(--indigo);
}

.lab-position {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--mid);
  white-space: nowrap;
}

/* Monaco whole-line highlight for the executing // @step line. */
.lab-step-line {
  background: rgba(92, 107, 255, 0.22);
}

@media (prefers-reduced-motion: reduce) {
  .lab-screen * {
    transition: none !important;
  }
}

/* ---- Narrow screens: catalogue on top, stacked panes, code collapsed ---- */
@media (max-width: 900px) {
  .lab-code-pane {
    min-width: 180px;
  }
}

@media (max-width: 768px) {
  .lab-screen .header {
    flex-wrap: wrap;
  }

  .lab-entry {
    min-height: 44px;
  }

  .lab-btn {
    min-height: 40px;
    min-width: 40px;
  }

  .lab-screen .header-actions {
    position: static;
    display: flex;
    flex-direction: row;
    width: auto;
    padding: 0;
    border: 0;
    background: transparent;
    box-shadow: none;
    margin-left: auto;
  }

  .lab-screen .header-actions .nav-btn {
    width: auto;
    justify-content: center;
    padding: 6px 8px;
  }

  .lab-layout {
    flex-direction: column;
  }

  .lab-list {
    width: 100%;
    min-width: 0;
    max-height: 118px;
    display: flex;
    align-items: flex-start;
    overflow-x: auto;
    overflow-y: hidden;
    border-right: 0;
    border-bottom: 1px solid var(--border);
    padding: 6px;
    gap: 6px;
  }

  .lab-category {
    display: none;
  }

  .lab-entry {
    min-width: 172px;
    max-width: 200px;
    margin-bottom: 0;
  }

  .lab-panes {
    flex-direction: column;
    padding: 8px;
    gap: 8px;
  }

  .lab-pane-body {
    flex-direction: column;
  }

  .lab-code-pane {
    width: 100%;
    min-width: 0;
    max-width: none;
    border-right: 0;
    border-bottom: 1px solid var(--border-soft);
  }

  .lab-code-pane.collapsed {
    border-bottom: 0;
  }

  .lab-editor {
    min-height: 180px;
  }

  .lab-view {
    min-height: 220px;
  }

  .lab-controls {
    gap: 8px;
  }

  .lab-position {
    width: 100%;
    text-align: left;
  }
}