/* ==========================================================================
   Baby Tracker - Mobile-First Vanilla CSS Design System
   ========================================================================== */

:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: #1e293b;
  --bg-card-hover: #334155;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: #334155;

  /* Accent Colors */
  --color-wake: #f59e0b;
  --color-sleep: #6366f1;
  --color-nursing-start: #ec4899;
  --color-nursing-end: #14b8a6;
  
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --shadow-main: 0 10px 25px -5px rgba(0, 0, 0, 0.4), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
  --shadow-active: 0 0 35px -5px currentColor;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  height: 100%;
  width: 100%;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  overflow-x: hidden;
  user-select: none;
  -webkit-user-select: none;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 18px;
  background: rgba(30, 41, 59, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  z-index: 50;
  position: sticky;
  top: 0;
}

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

.brand-icon {
  font-size: 1.5rem;
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #f8fafc 0%, #cbd5e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: 9999px;
  background: var(--bg-card);
  color: var(--text-primary);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 600;
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}

.nav-link:active {
  transform: scale(0.96);
  background: var(--bg-card-hover);
}

.nav-link.active-nav {
  background: #3b82f6;
  border-color: #60a5fa;
  color: #ffffff;
}

/* ==========================================================================
   Main Screen (4 Big Buttons Grid)
   ========================================================================== */

.main-container {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 12px;
  max-width: 600px;
  margin: 0 auto;
  width: 100%;
  height: calc(100dvh - 61px);
  justify-content: space-between;
}

.buttons-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 12px;
  flex: 1;
  margin-bottom: 12px;
}

/* Large Action Buttons */
.action-btn {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  cursor: pointer;
  padding: 14px 10px;
  transition: all 0.22s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: var(--shadow-main);
  outline: none;
  overflow: hidden;
}

.action-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, rgba(255, 255, 255, 0.15), transparent 70%);
  opacity: 0;
  transition: opacity 0.2s ease;
}

.action-btn:active {
  transform: scale(0.96);
}

.action-btn:active::before {
  opacity: 1;
}

/* Button Variants */
.btn-despertar {
  background: linear-gradient(160deg, #2a2216 0%, #1f1810 100%);
  color: #fbbf24;
  border-color: rgba(245, 158, 11, 0.25);
}

.btn-dormir {
  background: linear-gradient(160deg, #1e1e38 0%, #14142b 100%);
  color: #a5b4fc;
  border-color: rgba(99, 102, 241, 0.25);
}

.btn-empieza-teta-izq {
  background: linear-gradient(160deg, #2d1828 0%, #20111d 100%);
  color: #f472b6;
  border-color: rgba(236, 72, 153, 0.25);
}

.btn-empieza-teta-der {
  background: linear-gradient(160deg, #2d141e 0%, #200f16 100%);
  color: #fb7185;
  border-color: rgba(244, 63, 94, 0.25);
}

.btn-last-time {
  display: block;
  font-size: 0.72rem;
  color: rgba(255, 255, 255, 0.65);
  margin-top: 4px;
  font-weight: 500;
}

/* ACTIVE / SELECTED STATE */
.action-btn.is-active {
  transform: scale(1.015);
  border-width: 3px;
}

.btn-despertar.is-active {
  background: linear-gradient(145deg, #d97706, #b45309);
  color: #ffffff;
  border-color: #fef3c7;
  box-shadow: 0 0 35px rgba(245, 158, 11, 0.55);
}

.btn-dormir.is-active {
  background: linear-gradient(145deg, #4f46e5, #3730a3);
  color: #ffffff;
  border-color: #e0e7ff;
  box-shadow: 0 0 35px rgba(99, 102, 241, 0.55);
}

.btn-empieza-teta-izq.is-active {
  background: linear-gradient(145deg, #db2777, #9d174d);
  color: #ffffff;
  border-color: #fce7f3;
  box-shadow: 0 0 35px rgba(236, 72, 153, 0.55);
}

.btn-empieza-teta-der.is-active {
  background: linear-gradient(145deg, #e11d48, #9f1239);
  color: #ffffff;
  border-color: #ffe4e6;
  box-shadow: 0 0 35px rgba(244, 63, 94, 0.55);
}

.btn-termina-teta.is-active {
  background: linear-gradient(145deg, #0d9488, #115e59);
  color: #ffffff;
  border-color: #ccfbf1;
  box-shadow: 0 0 35px rgba(20, 184, 166, 0.55);
}

/* Live Stopwatch (Cronómetro) */
.stopwatch-display {
  display: none;
  align-items: center;
  gap: 6px;
  background: rgba(0, 0, 0, 0.45);
  border: 1px solid rgba(255, 255, 255, 0.25);
  padding: 4px 12px;
  border-radius: 9999px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  margin-top: 6px;
  color: #ffffff;
}

.action-btn.is-active .stopwatch-display {
  display: inline-flex;
}

.stopwatch-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: #ef4444;
  animation: blink 1s infinite alternate;
}

@keyframes blink {
  0% { opacity: 0.25; transform: scale(0.85); }
  100% { opacity: 1; transform: scale(1.15); }
}

/* Button Internal Content */
.btn-icon-wrapper {
  position: relative;
  font-size: 2.8rem;
  margin-bottom: 6px;
  line-height: 1;
  transition: transform 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.action-btn:active .btn-icon-wrapper {
  transform: scale(1.15);
}

.btn-title {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin-bottom: 4px;
}

.btn-subtitle {
  font-size: 0.8rem;
  opacity: 0.75;
  font-weight: 500;
}

/* Active Status Pill inside button */
.active-pill {
  position: absolute;
  top: 12px;
  right: 12px;
  background: rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(8px);
  padding: 3px 8px;
  border-radius: 9999px;
  font-size: 0.65rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #fff;
  display: none;
  animation: pulse 2s infinite ease-in-out;
}

.action-btn.is-active .active-pill {
  display: inline-block;
}

@keyframes pulse {
  0%, 100% { opacity: 0.85; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.06); }
}

/* ==========================================================================
   Footer Status Bar (Last Event Info)
   ========================================================================== */

.status-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  box-shadow: var(--shadow-main);
}

.status-left {
  display: flex;
  align-items: center;
  gap: 12px;
  overflow: hidden;
}

.status-icon-bubble {
  width: 44px;
  height: 44px;
  min-width: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
}

.status-text-group {
  display: flex;
  flex-direction: column;
}

.status-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  font-weight: 700;
}

.status-value {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.status-elapsed {
  font-size: 0.78rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-top: 2px;
}

.btn-undo {
  background: rgba(239, 68, 68, 0.15);
  color: #fca5a5;
  border: 1px solid rgba(239, 68, 68, 0.3);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.btn-undo:active {
  background: rgba(239, 68, 68, 0.3);
  transform: scale(0.95);
}

/* ==========================================================================
   Summary Screen (`resumen.php`)
   ========================================================================== */

.summary-container {
  max-width: 800px;
  margin: 0 auto;
  padding: 16px;
  width: 100%;
}

/* Date Filters Tabs */
.period-tabs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 12px;
}

.tab-btn {
  padding: 10px 8px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  transition: all 0.15s ease;
}

.tab-btn.active {
  background: #3b82f6;
  color: #fff;
  border-color: #60a5fa;
  font-weight: 700;
}

/* Custom Date Range Picker */
.custom-range-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  margin-bottom: 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.custom-range-card label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 600;
}

.custom-range-card input[type="date"] {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 6px 10px;
  border-radius: 8px;
  font-family: inherit;
  font-size: 0.85rem;
}

.btn-filter-submit {
  background: #3b82f6;
  border: none;
  color: #fff;
  padding: 7px 14px;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
}

/* Category Switcher Tabs (Lactancia / Sueño / Cronología) */
.category-nav {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  padding: 4px;
  border-radius: var(--radius-md);
  margin-bottom: 20px;
}

.category-tab {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 6px;
  border-radius: var(--radius-sm);
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.18s ease;
}

.category-tab:hover {
  color: var(--text-primary);
}

.category-tab.active {
  background: #3b82f6;
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.35);
}

.tab-pane {
  display: none;
}

.tab-pane.is-active-tab {
  display: block;
  animation: fadeIn 0.2s ease-in;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Triple KPI grid for Nursing (Total / Izquierda / Derecha) */
.kpi-triple-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 20px;
}

@media (max-width: 500px) {
  .kpi-triple-grid {
    grid-template-columns: 1fr;
  }
}

.kpi-card.kpi-teta-izq::before {
  background: linear-gradient(90deg, #ec4899, #db2777);
}

.kpi-card.kpi-teta-der::before {
  background: linear-gradient(90deg, #f43f5e, #e11d48);
}

.btn-wipe-all {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(239, 68, 68, 0.12);
  color: #f87171;
  border: 1px solid rgba(239, 68, 68, 0.35);
  padding: 12px 20px;
  border-radius: var(--radius-md);
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  margin: 30px auto 10px;
  transition: all 0.2s ease;
}

.btn-wipe-all:hover, .btn-wipe-all:active {
  background: rgba(239, 68, 68, 0.25);
  border-color: #ef4444;
  color: #ffffff;
}

/* KPI Summary Cards Grid */
.kpi-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 20px;
}

.kpi-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px;
  position: relative;
  overflow: hidden;
}

.kpi-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
}

.kpi-card.kpi-nursing::before {
  background: linear-gradient(90deg, #ec4899, #14b8a6);
}

.kpi-card.kpi-sleep::before {
  background: linear-gradient(90deg, #6366f1, #f59e0b);
}

.kpi-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.kpi-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-secondary);
}

.kpi-icon {
  font-size: 1.3rem;
}

.kpi-main-stat {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.1;
  margin-bottom: 4px;
}

.kpi-sub-stats {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.35;
}

.kpi-sub-stats strong {
  color: var(--text-primary);
}

/* Details Section */
.section-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 20px 0 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-primary);
}

.section-badge {
  font-size: 0.75rem;
  background: var(--bg-card-hover);
  padding: 2px 8px;
  border-radius: 999px;
  color: var(--text-secondary);
}

/* Timeline & Event List */
.timeline-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 30px;
}

.timeline-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}

.timeline-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.timeline-icon {
  font-size: 1.3rem;
}

.timeline-event-name {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
}

.timeline-event-time {
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.timeline-delete-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 1rem;
  cursor: pointer;
  padding: 6px;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.timeline-delete-btn:hover,
.timeline-delete-btn:active {
  color: #ef4444;
  background: rgba(239, 68, 68, 0.1);
}

/* Intervals Table / Card list */
.intervals-grid {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 24px;
}

.interval-row {
  background: var(--bg-secondary);
  border-left: 4px solid var(--border-color);
  border-radius: 4px var(--radius-sm) var(--radius-sm) 4px;
  padding: 10px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.88rem;
}

.interval-row.interval-nursing {
  border-left-color: #ec4899;
}

.interval-row.interval-sleep {
  border-left-color: #6366f1;
}

.interval-badge {
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 6px;
  font-size: 0.8rem;
}

.interval-nursing .interval-badge {
  background: rgba(236, 72, 153, 0.15);
  color: #f472b6;
}

.interval-sleep .interval-badge {
  background: rgba(99, 102, 241, 0.15);
  color: #a5b4fc;
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-muted);
}

.empty-state-icon {
  font-size: 2.5rem;
  margin-bottom: 8px;
  opacity: 0.5;
}

/* Toast Notifications */
.toast-msg {
  position: fixed;
  bottom: 85px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: rgba(15, 23, 42, 0.95);
  color: #fff;
  border: 1px solid var(--border-color);
  box-shadow: 0 10px 30px rgba(0,0,0,0.6);
  padding: 10px 18px;
  border-radius: 9999px;
  font-size: 0.88rem;
  font-weight: 600;
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: all 0.25s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.toast-msg.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Desktop tweaks */
@media (min-width: 600px) {
  .buttons-grid {
    gap: 18px;
  }
  .action-btn {
    padding: 24px;
  }
  .btn-title {
    font-size: 1.45rem;
  }
}