:root {
  --bg: #0f1420;
  --card: #1a2233;
  --card-2: #222c42;
  --text: #e8ecf4;
  --text-dim: #9aa6bd;
  --primary: #38bdf8;
  --primary-dark: #0ea5e9;
  --water: #22d3ee;
  --success: #34d399;
  --danger: #f87171;
  --border: #2c3a55;
  --radius: 14px;
}

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

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.app-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15, 20, 32, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  font-size: 24px;
  background: linear-gradient(135deg, var(--primary), var(--water));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.logo h1 {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.5px;
}

.nav-tabs {
  display: flex;
  gap: 8px;
}

.tab-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 8px 16px;
  border-radius: 999px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.tab-btn:hover {
  color: var(--text);
  border-color: var(--primary-dark);
}

.tab-btn.active {
  background: var(--primary);
  color: #06121f;
  border-color: var(--primary);
}

.app-main {
  max-width: 980px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.25s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

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

.card h2 {
  font-size: 18px;
  margin-bottom: 12px;
}

.card h3 {
  font-size: 15px;
  margin: 18px 0 10px;
  color: var(--text-dim);
}

.water-card .water-info {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 12px;
}

.water-info p {
  color: var(--text-dim);
  font-size: 14px;
}

.water-progress {
  height: 14px;
  background: var(--card-2);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 14px;
}

.water-progress.small {
  height: 10px;
  flex: 1;
  margin: 0;
}

.water-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--water));
  border-radius: 999px;
  transition: width 0.4s ease;
  min-width: 0;
}

.water-actions {
  display: flex;
  gap: 10px;
}

.water-actions .btn-water {
  flex: 1;
}

.btn {
  border: none;
  border-radius: 10px;
  padding: 10px 16px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.1s, opacity 0.2s;
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: var(--primary);
  color: #06121f;
}

.btn-primary:hover {
  background: var(--primary-dark);
}

.btn-secondary {
  background: var(--card-2);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--primary-dark);
}

.btn-water {
  background: rgba(34, 211, 238, 0.15);
  color: var(--water);
  border: 1px solid rgba(34, 211, 238, 0.4);
}

.btn-water:hover {
  background: rgba(34, 211, 238, 0.25);
}

.btn-undo {
  background: var(--card-2);
  color: var(--danger);
  border-color: rgba(248, 113, 113, 0.4);
}

.btn-full {
  width: 100%;
}

.hydration-timer-card {
  background: linear-gradient(135deg, rgba(34, 211, 238, 0.12), rgba(56, 189, 248, 0.06));
  border-color: rgba(34, 211, 238, 0.35);
  text-align: center;
}

.timer-display {
  font-size: 52px;
  font-weight: 800;
  color: var(--water);
  letter-spacing: 2px;
  margin: 6px 0;
  font-variant-numeric: tabular-nums;
}

#hydra-status {
  color: var(--text-dim);
  font-size: 13px;
  margin-bottom: 14px;
}

.timer-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

.session-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.session-header p {
  color: var(--text-dim);
  font-size: 14px;
}

.routines-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.routine-item {
  background: var(--card-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  transition: border-color 0.2s;
}

.routine-item:hover {
  border-color: var(--primary-dark);
}

.routine-item.selected {
  border-color: var(--primary);
  background: rgba(56, 189, 248, 0.1);
}

.routine-item h3 {
  font-size: 15px;
  color: var(--text);
  margin: 0;
}

.routine-item p {
  font-size: 12px;
  color: var(--text-dim);
  margin-top: 3px;
}

.routine-actions {
  display: flex;
  gap: 6px;
}

.icon-btn {
  background: var(--card);
  border: 1px solid var(--border);
  color: var(--text-dim);
  border-radius: 8px;
  width: 34px;
  height: 34px;
  cursor: pointer;
  font-size: 14px;
  transition: all 0.2s;
}

.icon-btn:hover {
  color: var(--text);
  border-color: var(--primary-dark);
}

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

.form-group {
  margin-bottom: 12px;
}

.form-group label {
  display: block;
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 6px;
  font-weight: 600;
}

.form-group input {
  width: 100%;
  background: var(--card-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  color: var(--text);
  font-family: inherit;
  font-size: 14px;
  outline: none;
  transition: border-color 0.2s;
}

.form-group input:focus {
  border-color: var(--primary);
}

.exercise-row {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr auto;
  gap: 8px;
  margin-bottom: 8px;
  align-items: center;
}

.exercise-row input {
  background: var(--card-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
  color: var(--text);
  font-family: inherit;
  font-size: 13px;
  outline: none;
}

.exercise-row input:focus {
  border-color: var(--primary);
}

.builder-actions {
  display: flex;
  gap: 10px;
  margin-top: 18px;
}

.builder-actions .btn {
  flex: 1;
}

.empty-state {
  text-align: center;
  color: var(--text-dim);
  padding: 24px 0;
  font-size: 14px;
}

.history-item {
  background: var(--card-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px;
  margin-bottom: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
}

.history-item h3 {
  font-size: 15px;
  color: var(--text);
  margin: 0;
}

.history-item p {
  font-size: 12px;
  color: var(--text-dim);
  margin-top: 3px;
}

.history-item .badge {
  background: rgba(52, 211, 153, 0.15);
  color: var(--success);
  border-radius: 999px;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 700;
  white-space: nowrap;
}

.modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  z-index: 100;
}

.modal-content {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 20px 20px 0 0;
  width: 100%;
  max-width: 720px;
  max-height: 85vh;
  padding: 20px;
  overflow-y: auto;
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.modal-header h2 {
  font-size: 20px;
}

.modal-water {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--card-2);
  border-radius: 12px;
  padding: 12px;
  margin-bottom: 16px;
}

.modal-water span:first-child {
  font-size: 20px;
}

#modal-water-text {
  font-size: 13px;
  color: var(--text-dim);
  font-weight: 600;
  min-width: 60px;
}

.active-exercises {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 16px;
}

.active-exercise {
  background: var(--card-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
}

.active-exercise h4 {
  font-size: 15px;
  margin-bottom: 8px;
}

.set-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 6px 0;
  border-top: 1px dashed var(--border);
}

.set-row:first-of-type {
  border-top: none;
}

.set-label {
  font-size: 13px;
  color: var(--text-dim);
  font-weight: 600;
}

.set-check {
  width: 22px;
  height: 22px;
  border: 2px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  color: transparent;
  transition: all 0.15s;
  flex-shrink: 0;
}

.set-check.checked {
  background: var(--success);
  border-color: var(--success);
  color: #052017;
}

.set-rest {
  font-size: 12px;
  color: var(--text-dim);
}

.active-exercise.done h4 {
  color: var(--success);
  text-decoration: line-through;
}

.modal-footer {
  padding-top: 4px;
}

@media (min-width: 768px) {
  .modal {
    align-items: center;
  }
  .modal-content {
    border-radius: 20px;
    max-height: 90vh;
  }
  .builder-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
}