/* ---------------------------------------------------------------
   Activity Time Explorer — Minimalistic dark-first theme
   System theme detection via prefers-color-scheme
   --------------------------------------------------------------- */

/* ---- Dark mode (default) ---- */
:root {
  --bg-main: #111111;
  --bg-sidebar: #161616;
  --bg-card: #1a1a1a;
  --bg-hover: #252525;
  --bg-input: #1e1e1e;
  --border: #2a2a2a;
  --border-subtle: #222222;
  --text-primary: #e4e4e7;
  --text-secondary: #9a9aa0;
  --text-muted: #636368;
  --accent: #2dd4a8;
  --accent-hover: #22b893;
  --accent-dim: rgba(45, 212, 168, 0.12);
  --danger: #ef4444;
  --bar-track: #222222;
  --radius: 8px;
  --sidebar-width: 260px;
  --font: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color-scheme: dark;
}

/* ---- Light mode (follows system) ---- */
@media (prefers-color-scheme: light) {
  :root {
    --bg-main: #fafafa;
    --bg-sidebar: #f3f3f3;
    --bg-card: #ffffff;
    --bg-hover: #ebebeb;
    --bg-input: #ffffff;
    --border: #e2e2e2;
    --border-subtle: #eeeeee;
    --text-primary: #1a1a1a;
    --text-secondary: #6b6b74;
    --text-muted: #9a9aa0;
    --accent: #10a37f;
    --accent-hover: #0d8a6a;
    --accent-dim: rgba(16, 163, 127, 0.08);
    --danger: #d1453b;
    --bar-track: #f0f0f0;
    color-scheme: light;
  }
}

/* ---- Reset ---- */
* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  font-family: var(--font);
  color: var(--text-primary);
  background: var(--bg-main);
  font-size: 13.5px;
  -webkit-font-smoothing: antialiased;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

.hidden { display: none !important; }
.muted  { color: var(--text-muted); font-weight: 400; }

/* ================ App Shell ================ */

.app {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ================ Sidebar ================ */

.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-width);
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 14px 12px;
  overflow-y: auto;
  transition: margin-left 0.2s ease;
}

.sidebar.collapsed {
  margin-left: calc(-1 * var(--sidebar-width));
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 4px 2px 16px 2px;
}

.brand {
  font-weight: 600;
  font-size: 14px;
  letter-spacing: -0.01em;
}

.icon-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 5px 7px;
  border-radius: 6px;
  font-size: 12px;
  transition: background 0.15s, color 0.15s;
}

.icon-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* ---- Upload tile ---- */

.upload-tile {
  display: flex;
  align-items: center;
  gap: 10px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 12px;
  cursor: pointer;
  margin-bottom: 12px;
  background: var(--bg-card);
  transition: border-color 0.15s, background 0.15s;
}

.upload-tile:hover {
  border-color: var(--accent);
  background: var(--accent-dim);
}

.upload-icon {
  font-size: 15px;
  color: var(--accent);
  font-weight: 600;
}

.upload-text {
  font-weight: 500;
  color: var(--text-primary);
  font-size: 13px;
}

/* ---- File meta ---- */

.file-meta {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 8px 10px;
  margin-bottom: 14px;
}

.file-meta-name {
  font-weight: 600;
  font-size: 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-meta-rows {
  color: var(--text-secondary);
  font-size: 11.5px;
  margin-top: 2px;
}

/* ---- Sidebar sections ---- */

.sidebar-section {
  margin-bottom: 14px;
}

.sidebar-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 6px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.text-input {
  width: 100%;
  padding: 7px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-input);
  color: var(--text-primary);
  outline: none;
  transition: border-color 0.15s;
}

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

.text-input:disabled,
.multi-select:disabled,
.range-input:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.date-row {
  display: flex;
  gap: 6px;
}

.date-row .text-input {
  min-width: 0;
}

.multi-select {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-input);
  color: var(--text-primary);
  padding: 4px;
  max-height: 100px;
}

.multi-select option {
  padding: 4px 6px;
  border-radius: 4px;
  font-size: 12px;
}

.range-input {
  width: 100%;
  accent-color: var(--accent);
}

.reset-btn {
  margin-top: auto;
  width: 100%;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  font-weight: 500;
  font-size: 12.5px;
  transition: background 0.15s, color 0.15s;
}

.reset-btn:hover:not(:disabled) {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.reset-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ================ Main Panel ================ */

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

.topbar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border);
}

.topbar-title {
  font-weight: 600;
  font-size: 14px;
  flex: 1;
  letter-spacing: -0.01em;
}

.secondary-btn {
  padding: 7px 14px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-primary);
  cursor: pointer;
  font-weight: 500;
  font-size: 12.5px;
  transition: background 0.15s;
}

.secondary-btn:hover:not(:disabled) {
  background: var(--bg-hover);
}

.secondary-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.content {
  flex: 1;
  overflow-y: auto;
  padding: 20px 28px 48px 28px;
}

/* ================ Empty State ================ */

.empty-state {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.empty-card {
  text-align: center;
  max-width: 420px;
}

.empty-icon {
  font-size: 36px;
  margin-bottom: 8px;
  opacity: 0.8;
}

.empty-card h1 {
  font-size: 20px;
  font-weight: 600;
  margin: 0 0 6px 0;
  letter-spacing: -0.02em;
}

.empty-card p {
  color: var(--text-secondary);
  line-height: 1.55;
  margin: 0 0 18px 0;
  font-size: 13px;
}

.empty-upload-btn {
  display: inline-block;
  padding: 9px 20px;
  background: var(--accent);
  color: #111;
  border-radius: 6px;
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s;
}

.empty-upload-btn:hover {
  background: var(--accent-hover);
}

.empty-hint {
  font-size: 11.5px;
  color: var(--text-muted) !important;
  margin-top: 12px !important;
}

/* ================ Metrics ================ */

.metrics-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}

.metric-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  background: var(--bg-card);
}

.metric-value {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.metric-label {
  color: var(--text-muted);
  font-size: 11.5px;
  margin-top: 3px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* ================ Tabs ================ */

.tabs {
  display: flex;
  gap: 2px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 14px;
}

.tab-btn {
  padding: 8px 14px;
  border: none;
  background: transparent;
  cursor: pointer;
  color: var(--text-muted);
  font-weight: 500;
  font-size: 13px;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: color 0.15s;
}

.tab-btn.active {
  color: var(--text-primary);
  border-bottom-color: var(--accent);
}

.tab-btn:hover:not(.active) {
  color: var(--text-secondary);
}

/* ================ Chart ================ */

.chart-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 18px;
  background: var(--bg-card);
  margin-bottom: 20px;
}

.chart-title {
  font-weight: 600;
  font-size: 13px;
  margin-bottom: 12px;
  color: var(--text-secondary);
}

.bar-chart {
  display: flex;
  flex-direction: column;
  gap: 6px;
  max-height: 580px;
  overflow-y: auto;
}

.bar-row {
  display: grid;
  grid-template-columns: 160px 1fr 65px;
  align-items: center;
  gap: 10px;
  font-size: 12px;
}

.bar-row .bar-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-secondary);
  cursor: default;
}

.bar-track {
  background: var(--bar-track);
  border-radius: 3px;
  height: 16px;
  position: relative;
  overflow: hidden;
}

.bar-fill {
  background: var(--accent);
  height: 100%;
  border-radius: 3px;
  transition: width 0.25s ease;
}

.bar-row .bar-value {
  text-align: right;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  font-size: 11.5px;
}

.chart-empty {
  color: var(--text-muted);
  padding: 20px 0;
  text-align: center;
  font-size: 12.5px;
}

/* ================ Table ================ */

.table-section {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  padding: 16px 18px 10px 18px;
}

.table-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.table-header h2 {
  font-size: 14px;
  font-weight: 600;
}

.table-wrap {
  overflow-x: auto;
  max-height: 440px;
  overflow-y: auto;
  border-top: 1px solid var(--border);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
}

thead th {
  position: sticky;
  top: 0;
  background: var(--bg-sidebar);
  text-align: left;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  color: var(--text-muted);
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

thead th:hover {
  background: var(--bg-hover);
}

thead th .sort-indicator {
  margin-left: 4px;
  color: var(--text-muted);
}

tbody td {
  padding: 7px 10px;
  border-bottom: 1px solid var(--border-subtle);
  white-space: nowrap;
  max-width: 300px;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-secondary);
}

tbody tr:hover {
  background: var(--bg-hover);
}

.pagination {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-muted);
}

.pagination button {
  border: 1px solid var(--border);
  background: var(--bg-card);
  border-radius: 5px;
  padding: 4px 10px;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 12px;
  transition: background 0.15s;
}

.pagination button:hover:not(:disabled) {
  background: var(--bg-hover);
}

.pagination button:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

/* ================ Toast ================ */

.toast {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg-card);
  color: var(--text-primary);
  padding: 9px 18px;
  border-radius: 6px;
  font-size: 12.5px;
  border: 1px solid var(--border);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
  z-index: 999;
}

.toast.error {
  border-color: var(--danger);
  color: var(--danger);
}

/* ================ Scrollbar ================ */

::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ================ Responsive ================ */

@media (max-width: 900px) {
  .metrics-row {
    grid-template-columns: repeat(2, 1fr);
  }
  .sidebar {
    position: fixed;
    z-index: 50;
    height: 100vh;
  }
}