*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, sans-serif;
  line-height: 1.5;
  color: #1a1a1a;
  background: #f5f5f5;
  overflow-x: hidden;
}

.layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  grid-template-rows: auto auto auto;
  gap: 1rem;
  min-height: 100vh;
  padding: 1.5rem;
  padding-top: max(1.5rem, env(safe-area-inset-top));
  padding-left: max(1.5rem, env(safe-area-inset-left));
  padding-right: max(1.5rem, env(safe-area-inset-right));
  padding-bottom: max(1.5rem, env(safe-area-inset-bottom));
  max-width: 800px;
  margin: 0 auto;
  align-content: start;
}

.layout header {
  grid-column: 1 / -1;
  grid-row: 1;
}

.stats-card {
  grid-column: 1;
  grid-row: 2;
  background: #fff;
  border-radius: 8px;
  padding: 1.25rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  overflow-y: auto;
  min-height: 0;
}

.app-sections-top {
  grid-column: 2;
  grid-row: 2;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  min-width: 0;
  max-width: 480px;
}

.app-sections-top section {
  margin-bottom: 0;
}

.data-io-card {
  grid-column: 1;
  grid-row: 3;
  align-self: stretch;
  display: flex;
  flex-direction: column;
  min-height: 0;
  height: 100%;
  background: #fff;
  border-radius: 8px;
  padding: 1.25rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.data-io-card h2 {
  margin: 0 0 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: #555;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  text-align: center;
}

.data-io-buttons {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.data-io-card .data-io-buttons button {
  min-width: 0;
}

.layout .recent-sessions {
  grid-column: 2;
  grid-row: 3;
  align-self: stretch;
  height: 100%;
  margin-bottom: 0;
}

.stats-card h2 {
  margin: 0 0 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: #555;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  text-align: center;
}

.stats-range {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.35rem;
  margin-bottom: 1.25rem;
}

.stats-range-btn {
  padding: 0.4rem 0.65rem;
  font-size: 0.8125rem;
  min-width: auto;
  background: #eee;
  color: #333;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

.stats-range-btn:hover {
  background: #e0e0e0;
}

.stats-range-btn.active {
  background: #333;
  color: #fff;
}

.stats-chart-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  max-width: 200px;
  margin: 0 auto 1.25rem;
  overflow: visible;
}

.stats-pie-chart {
  width: 100%;
  height: 100%;
  display: block;
  overflow: visible;
}

.stats-no-data {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  font-size: 0.875rem;
  color: #888;
  text-align: center;
}

.stats-no-data[hidden] {
  display: none !important;
}

.stats-category-list {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.875rem;
}

.stats-category-list li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0;
  border-bottom: 1px solid #f0f0f0;
}

.stats-cat-swatch {
  flex-shrink: 0;
  width: 0.65rem;
  height: 0.65rem;
  border-radius: 50%;
}

.stats-category-list li:last-child {
  border-bottom: none;
}

.stats-category-list .stats-cat-name {
  flex: 1;
  min-width: 0;
  font-weight: 500;
}

.stats-category-list .stats-cat-duration {
  flex-shrink: 0;
  color: #666;
  font-variant-numeric: tabular-nums;
}

.layout header {
  margin-bottom: 1.5rem;
  text-align: center;
}

header h1 {
  margin: 0;
  font-size: 1.75rem;
  font-weight: 700;
}

section {
  background: #fff;
  border-radius: 8px;
  padding: 1.25rem;
  margin-bottom: 1rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

section h2 {
  margin: 0 0 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: #555;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  text-align: center;
}

.add-category {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

#category-input {
  flex: 1;
  padding: 0.5rem 0.75rem;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 6px;
}

#category-input:focus {
  outline: none;
  border-color: #333;
  box-shadow: 0 0 0 2px rgba(0, 0, 0, 0.1);
}

button {
  padding: 0.5rem 1rem;
  font-size: 0.9375rem;
  font-weight: 500;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  background: #333;
  color: #fff;
}

button:hover:not(:disabled) {
  background: #222;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.category-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.category-list li {
  padding: 0.5rem 0.75rem;
  margin-bottom: 0.25rem;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.15s;
}

.category-list li:hover {
  background: #f0f0f0;
}

.category-list li.selected {
  background: #e0e0e0;
  font-weight: 500;
}

.no-categories-msg,
.no-sessions-msg {
  margin: 0;
  color: #666;
  font-size: 0.9375rem;
  text-align: center;
}

.selected-category {
  margin: 0 0 1rem;
  font-size: 0.9375rem;
  color: #555;
  text-align: center;
}

.stopwatch {
  font-size: 2.5rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  text-align: center;
  margin-bottom: 1rem;
  min-height: 3rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.session-controls .buttons {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
}

#start-session-btn,
#stop-session-btn {
  min-width: 140px;
}

.session-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.session-list li {
  padding: 0.5rem 0;
  border-bottom: 1px solid #eee;
  font-size: 0.9375rem;
}

.session-list li:last-child {
  border-bottom: none;
}

.session-item-view {
  display: grid;
  grid-template-columns: 1fr 5.25rem auto;
  align-items: center;
  gap: 0.75rem 1rem;
}

.session-list .session-category {
  font-weight: 500;
  min-width: 0;
}

.session-list .session-duration {
  color: #666;
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.session-actions {
  display: flex;
  gap: 0.25rem;
  flex-shrink: 0;
}

.icon-btn {
  padding: 0.35rem;
  min-width: auto;
  background: transparent;
  color: #555;
  border-radius: 6px;
}

.icon-btn:hover {
  background: #eee;
  color: #1a1a1a;
}

.session-edit-form {
  padding: 0.75rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.session-edit-row {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.session-edit-row label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: #555;
}

.session-edit-form select,
.session-edit-form input[type="datetime-local"] {
  padding: 0.5rem 0.75rem;
  font-size: 0.9375rem;
  border: 1px solid #ccc;
  border-radius: 6px;
}

.session-edit-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.25rem;
}

.session-edit-cancel {
  background: #e0e0e0;
  color: #1a1a1a;
}

.session-edit-cancel:hover {
  background: #d0d0d0;
}

@media (max-width: 768px) {
  .layout {
    grid-template-columns: 1fr;
    grid-template-rows: auto;
    padding: 1rem;
    padding-top: max(1rem, env(safe-area-inset-top));
    padding-left: max(1rem, env(safe-area-inset-left));
    padding-right: max(1rem, env(safe-area-inset-right));
    padding-bottom: max(1rem, env(safe-area-inset-bottom));
    gap: 1rem;
  }

  .layout header {
    grid-column: 1;
    grid-row: 1;
  }

  .app-sections-top {
    grid-column: 1;
    grid-row: 2;
    max-width: none;
  }

  .layout .recent-sessions {
    grid-column: 1;
    grid-row: 3;
    height: auto;
    align-self: auto;
  }

  .stats-card {
    grid-column: 1;
    grid-row: 4;
    height: auto;
  }

  .data-io-card {
    grid-column: 1;
    grid-row: 5;
    height: auto;
    align-self: auto;
  }

  button {
    min-height: 44px;
    padding: 0.6rem 1rem;
  }

  .icon-btn {
    min-height: 44px;
    min-width: 44px;
    padding: 0.35rem;
  }

  .stats-range-btn {
    min-height: 40px;
  }

  .category-list li {
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  .stopwatch {
    font-size: 2rem;
  }

  section {
    padding: 1rem;
  }

  .stats-chart-wrap {
    max-width: 180px;
  }
}