/* ============================================================
   STARKDB LAB — Complete Lab Stylesheet
   ============================================================ */

/* ---- Lab Layout ---- */
.lab-layout {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem 4rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: auto auto;
  gap: 2rem;
}
.lab-section-title {
  font-size: .65rem;
  font-family: 'Space Mono', monospace;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 8px;
}
.lab-section-title::before {
  content: '';
  width: 12px;
  height: 1px;
  background: var(--accent);
}
.lab-terminal-section {
  grid-column: 1;
  grid-row: 1;
  min-height: 420px;
  display: flex;
  flex-direction: column;
}
.lab-panels-section {
  grid-column: 2;
  grid-row: 1;
  min-height: 420px;
  display: flex;
  flex-direction: column;
}
.lab-quick-section {
  grid-column: 1 / -1;
  grid-row: 2;
}

/* ---- Terminal Wrapper ---- */
.lab-terminal-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  box-shadow: 0 0 40px rgba(232, 255, 71, 0.03);
}
.terminal-topbar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  background: rgba(20, 20, 28, 0.95);
  border-bottom: 1px solid var(--border);
}
.terminal-dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
  flex-shrink: 0;
}
.dot-red { background: #ff5f57; }
.dot-yellow { background: #ffbd2e; }
.dot-green { background: #28c840; }
.terminal-title {
  font-family: 'Space Mono', monospace;
  font-size: .6rem;
  color: var(--muted);
  letter-spacing: .05em;
  margin-left: 6px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ---- Terminal Output ---- */
.lab-terminal {
  flex: 1;
  padding: 0.75rem 1rem;
  overflow-y: auto !important;
  min-height: 280px;
  max-height: 420px;
  font-family: 'Space Mono', monospace;
  font-size: .78rem;
  line-height: 1.65;
}
.lab-terminal::-webkit-scrollbar {
  width: 4px;
}
.lab-terminal::-webkit-scrollbar-track {
  background: transparent;
}
.lab-terminal::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 2px;
}
.terminal-line {
  white-space: pre-wrap;
  word-break: break-all;
  padding: 1px 0;
  animation: fadeInLine .15s ease;
}
@keyframes fadeInLine {
  from { opacity: 0; transform: translateY(2px); }
  to { opacity: 1; transform: translateY(0); }
}
.cmd-echo {
  color: var(--accent);
}
.output-success {
  color: #47ff8a;
}
.output-error {
  color: var(--accent3);
}
.output-info {
  color: var(--accent2);
}
.output-text {
  color: #c0c0e0;
}
.output-warning {
  color: var(--accent5);
}

/* ---- Terminal Input ---- */
.terminal-input-line {
  display: flex;
  align-items: center;
  padding: 0.5rem 1rem 0.75rem;
  border-top: 1px solid var(--border);
  background: rgba(10, 10, 15, 0.8);
}
.terminal-prompt {
  font-family: 'Space Mono', monospace;
  font-size: .78rem;
  color: var(--accent);
  white-space: nowrap;
  margin-right: 6px;
  font-weight: 700;
}
.terminal-input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  font-family: 'Space Mono', monospace;
  font-size: .78rem;
  color: var(--text);
  caret-color: var(--accent);
  padding: 0;
}
.terminal-input::placeholder {
  color: #3a3a5a;
}

/* ---- Lab Tabs ---- */
.lab-tabs-container {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
}
.lab-tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
}
.lab-tab-btn {
  font-family: 'Space Mono', monospace;
  font-size: .68rem;
  padding: 10px 16px;
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  letter-spacing: .06em;
  white-space: nowrap;
  position: relative;
  transition: color .2s;
}
.lab-tab-btn.active {
  color: var(--accent);
}
.lab-tab-btn.active::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent);
}
.lab-tab-panel {
  display: none;
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  min-height: 260px;
}
.lab-tab-panel.active {
  display: flex !important;
  flex-direction: column;
}
.lab-tab-panel::-webkit-scrollbar {
  width: 4px;
}
.lab-tab-panel::-webkit-scrollbar-track {
  background: transparent;
}
.lab-tab-panel::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 2px;
}

/* ---- DB Inspector ---- */
.db-inspector {
  font-family: 'Space Mono', monospace;
  font-size: .72rem;
}
.inspector-empty {
  color: var(--muted);
  text-align: center;
  padding: 2rem 1rem;
  line-height: 1.8;
}
.inspector-empty code {
  background: rgba(232, 255, 71, .07);
  border: 1px solid rgba(232, 255, 71, .15);
  padding: 2px 7px;
  color: var(--accent);
}
.inspector-section {
  margin-bottom: 1.2rem;
}
.inspector-title {
  font-size: .62rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  padding: 6px 10px;
  margin-bottom: 8px;
  border-radius: 2px;
  display: inline-block;
}
.inspector-title.accent {
  color: var(--accent);
  background: rgba(232, 255, 71, .06);
  border: 1px solid rgba(232, 255, 71, .15);
}
.inspector-title.accent2 {
  color: var(--accent2);
  background: rgba(71, 255, 232, .06);
  border: 1px solid rgba(71, 255, 232, .15);
}
.inspector-title.accent3 {
  color: var(--accent3);
  background: rgba(255, 107, 71, .06);
  border: 1px solid rgba(255, 107, 71, .15);
}
.inspector-row {
  display: flex;
  gap: 8px;
  padding: 4px 6px;
  border-bottom: 1px solid rgba(42, 42, 56, .4);
  align-items: baseline;
  transition: background .15s;
}
.inspector-row:hover {
  background: rgba(255, 255, 255, .02);
}
.inspector-key {
  color: var(--accent);
  flex-shrink: 0;
  min-width: 30px;
}
.inspector-arrow {
  color: var(--muted);
  font-size: .65rem;
}
.inspector-val {
  color: #c0c0e0;
  word-break: break-all;
}
.inspector-type-name {
  font-size: .7rem;
  color: var(--accent3);
  margin: 8px 0 4px;
  font-weight: 600;
}
.inspector-fields {
  color: var(--muted);
  font-weight: 400;
  font-size: .62rem;
}

/* ---- B-Tree Controls ---- */
.btree-controls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 12px;
}
.btree-control-row {
  display: flex;
  gap: 6px;
}
.btree-control-row:last-child {
  grid-column: 1 / -1;
}
.btree-control-row input {
  flex: 1;
  min-width: 0;
  background: var(--code-bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: 'Space Mono', monospace;
  font-size: .7rem;
  padding: 6px 10px;
  border-radius: 3px;
  outline: none;
  transition: border-color .2s;
}
.btree-control-row input:focus {
  border-color: var(--accent);
}
.btree-control-row input::placeholder {
  color: #3a3a5a;
}
.btree-control-row input[type="number"]::-webkit-inner-spin-button,
.btree-control-row input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.btree-control-row input[type="number"] {
  -moz-appearance: textfield;
}

.btree-btn {
  font-family: 'Space Mono', monospace;
  font-size: .65rem;
  padding: 6px 12px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--muted);
  cursor: pointer;
  letter-spacing: .08em;
  text-transform: uppercase;
  border-radius: 3px;
  transition: all .2s;
  white-space: nowrap;
}
.btree-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
}
.btree-insert { color: #47ff8a; border-color: rgba(71, 255, 138, .3); }
.btree-insert:hover { color: #47ff8a; border-color: #47ff8a; background: rgba(71, 255, 138, .06); }
.btree-search { color: var(--accent2); border-color: rgba(71, 255, 232, .3); }
.btree-search:hover { color: var(--accent2); border-color: var(--accent2); background: rgba(71, 255, 232, .06); }
.btree-delete { color: var(--accent3); border-color: rgba(255, 107, 71, .3); }
.btree-delete:hover { color: var(--accent3); border-color: var(--accent3); background: rgba(255, 107, 71, .06); }
.btree-reset { color: var(--accent4); border-color: rgba(196, 127, 255, .3); }
.btree-reset:hover { color: var(--accent4); border-color: var(--accent4); background: rgba(196, 127, 255, .06); }

.btree-feedback {
  font-family: 'Space Mono', monospace;
  font-size: .68rem;
  color: var(--accent2);
  text-align: center;
  margin-bottom: 8px;
  height: 20px;
  opacity: 0;
  transition: opacity .2s;
}
.btree-canvas {
  flex: 1;
  min-height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(10, 10, 15, .4);
  border: 1px solid var(--border);
  border-radius: 4px;
  margin-bottom: 10px;
  overflow: hidden;
}
.btree-info {
  padding: 8px 0;
}
.btree-info p {
  font-size: .68rem;
  color: var(--muted);
  line-height: 1.6;
  margin: 0;
}

/* ---- Hash Explorer ---- */
.hash-controls {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
}
.hash-controls input {
  flex: 1;
  background: var(--code-bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: 'Space Mono', monospace;
  font-size: .72rem;
  padding: 7px 12px;
  border-radius: 3px;
  outline: none;
  transition: border-color .2s;
}
.hash-controls input:focus {
  border-color: var(--accent);
}
.hash-controls button {
  padding: 7px 16px;
}
.hash-quick {
  font-family: 'Space Mono', monospace;
  font-size: .72rem;
  color: var(--accent2);
  text-align: center;
  margin-bottom: 10px;
  padding: 8px;
  background: rgba(71, 255, 232, .04);
  border: 1px solid rgba(71, 255, 232, .12);
  border-radius: 3px;
  transition: all .2s;
}
.hash-steps {
  font-family: 'Space Mono', monospace;
}
.hash-title {
  font-size: .65rem;
  color: var(--accent);
  letter-spacing: .1em;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.hash-formula {
  font-size: .62rem;
  color: var(--muted);
  margin-bottom: 12px;
  padding: 4px 10px;
  background: rgba(232, 255, 71, .04);
  border: 1px solid rgba(232, 255, 71, .1);
  border-radius: 3px;
  display: inline-block;
}
.hash-step {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 3px 0;
  font-size: .68rem;
  border-bottom: 1px solid rgba(42, 42, 56, .3);
  animation: fadeInLine .3s ease;
}
.hash-num {
  color: var(--muted);
  font-size: .6rem;
  min-width: 20px;
  text-align: right;
}
.hash-char {
  color: var(--accent3);
  min-width: 30px;
  font-weight: 600;
}
.hash-code {
  color: var(--accent5);
  min-width: 80px;
}
.hash-calc {
  color: #c0c0e0;
  font-size: .65rem;
  word-break: break-all;
}
.hash-result {
  margin-top: 12px;
  padding: 8px 12px;
  font-size: .7rem;
  color: var(--accent);
  background: rgba(232, 255, 71, .06);
  border: 1px solid rgba(232, 255, 71, .15);
  border-radius: 3px;
}
.hash-result strong {
  color: var(--accent);
  font-size: .85rem;
}
.hash-info {
  margin-top: 10px;
}
.hash-info p {
  font-size: .68rem;
  color: var(--muted);
  line-height: 1.6;
  margin: 0;
}

/* ---- Challenges ---- */
.challenge-card {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color .2s;
}
.challenge-card:hover {
  border-color: rgba(232, 255, 71, .15);
}
.challenge-header {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 10px 12px;
}
.challenge-num {
  font-family: 'Syne', sans-serif;
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  min-width: 28px;
}
.challenge-title {
  font-size: .75rem;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 3px;
}
.challenge-desc {
  font-family: 'Space Mono', monospace;
  font-size: .65rem;
  color: var(--muted);
  line-height: 1.5;
}
.challenge-check {
  font-family: 'Space Mono', monospace;
  font-size: .6rem;
  padding: 5px 10px;
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--muted);
  cursor: pointer;
  letter-spacing: .06em;
  text-transform: uppercase;
  border-radius: 3px;
  margin-left: auto;
  flex-shrink: 0;
  transition: all .2s;
}
.challenge-check:hover {
  color: var(--accent);
  border-color: var(--accent);
}
.challenge-check.done {
  background: rgba(71, 255, 138, .1);
  border-color: #47ff8a;
  color: #47ff8a;
  cursor: default;
}
.challenge-check.fail {
  background: rgba(255, 71, 71, .1);
  border-color: #ff4747;
  color: #ff4747;
}
.challenge-hint {
  padding: 0 12px 10px;
}
.challenge-hint pre {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 10px;
  margin: 0;
}
.challenge-hint pre code {
  font-size: .65rem;
  line-height: 1.7;
  color: #a0a0c0;
}
.challenge-hint-btn {
  display: block;
  width: 100%;
  font-family: 'Space Mono', monospace;
  font-size: .6rem;
  padding: 7px;
  background: none;
  border: none;
  border-top: 1px solid var(--border);
  color: var(--muted);
  cursor: pointer;
  letter-spacing: .08em;
  text-transform: uppercase;
  transition: color .2s;
}
.challenge-hint-btn:hover {
  color: var(--accent2);
}

/* ---- Quick Commands ---- */
.quick-cmds {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.quick-cmd {
  font-family: 'Space Mono', monospace;
  font-size: .65rem;
  padding: 7px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--muted);
  cursor: pointer;
  border-radius: 3px;
  letter-spacing: .05em;
  transition: all .2s;
  max-width: 260px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.quick-cmd:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: rgba(232, 255, 71, .04);
  transform: translateY(-1px);
  box-shadow: 0 2px 12px rgba(232, 255, 71, .06);
}

/* ---- Lab Responsive ---- */
@media (max-width: 1100px) {
  .lab-layout {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
    padding: 0 1.5rem 3rem;
    gap: 1.5rem;
  }
  .lab-terminal-section { grid-column: 1; grid-row: 1; min-height: 380px; }
  .lab-panels-section { grid-column: 1; grid-row: 2; min-height: 380px; }
  .lab-quick-section { grid-column: 1; grid-row: 3; }
}

@media (max-width: 750px) {
  .lab-layout {
    padding: 0 1rem 2rem;
    gap: 1.25rem;
  }
  .lab-terminal-section { min-height: 340px; }
  .lab-panels-section { min-height: 340px; }
  .lab-terminal {
    font-size: .7rem;
    max-height: 300px;
  }
  .terminal-input {
    font-size: .7rem;
  }
  .terminal-prompt {
    font-size: .7rem;
  }
  .btree-controls {
    grid-template-columns: 1fr;
  }
  .lab-tab-btn {
    font-size: .6rem;
    padding: 8px 10px;
  }
  .quick-cmd {
    font-size: .58rem;
    padding: 6px 10px;
  }
  .btree-canvas {
    min-height: 160px;
  }
}