* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: #f8f9fb;
  color: #333;
  line-height: 1.6;
}

/* Navbar */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #fff;
  padding: 15px 40px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar .logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: bold;
  color: #222;
  cursor: pointer;
}

.navbar .logo:hover {
  opacity: 0.8;
}

.navbar .logo span {
  background: #2563eb;
  color: #fff;
  padding: 5px 10px;
  border-radius: 6px;
  font-weight: bold;
  transition: transform 0.2s;
}

.navbar .logo:hover span {
  transform: scale(1.05);
}

.navbar .right-text {
  font-size: 14px;
  color: #666;
}

/* Menu */
.menu {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  padding: 15px;
  background: #fff;
  border-bottom: 1px solid #eee;
}

.menu button {
  background: #fff;
  border: 1px solid #ddd;
  padding: 8px 16px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 14px;
  transition: 0.2s;
}

.menu button:hover {
  background: #2563eb;
  color: #fff;
  border-color: #2563eb;
}

/* Hero */
.hero {
  text-align: center;
  padding: 60px 20px;
}

.hero .circle {
  width: 60px;
  height: 60px;
  background: #e8f0fe;
  color: #2563eb;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 22px;
  margin: 0 auto 20px;
}

.hero h1 {
  font-size: 24px;
  margin-bottom: 10px;
}

.hero p {
  max-width: 600px;
  margin: 0 auto;
  font-size: 14px;
  color: #555;
}

/* Tools */
.tools {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 20px;
  padding: 40px;
  max-width: 900px;
  margin: 0 auto;
}

.tool-card {
  background: #fff;
  border: 1px solid #eee;
  border-radius: 12px;
  padding: 20px;
  text-align: center;
  cursor: pointer;
  transition: 0.2s;
}

.tool-card:hover {
  border-color: #2563eb;
  transform: translateY(-3px);
  box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}

.tool-card i {
  font-size: 28px;
  color: #2563eb;
  margin-bottom: 10px;
}

.tool-card p {
  margin: 0;
  font-weight: 500;
  color: #333;
}

/* To-Do */
.todo-container {
  max-width: 700px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.todo-input {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}

.todo-input input {
  flex: 1;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 6px;
}

.todo-input button {
  background: #2563eb;
  border: none;
  color: #fff;
  padding: 10px 15px;
  border-radius: 6px;
  cursor: pointer;
}

.todo-list {
  list-style: none;
  padding: 0;
}

.todo-list li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px;
  border: 1px solid #eee;
  border-radius: 6px;
  margin-bottom: 10px;
  background: #fafafa;
}

.todo-list li.completed span {
  text-decoration: line-through;
  color: #777;
}

.btn-group {
  display: flex;
  gap: 5px;
}

.delete-btn {
  background: #ff4d4d;
  border: none;
  color: #fff;
  padding: 5px 10px;
  border-radius: 6px;
  cursor: pointer;
}

.done-btn {
  background: #16a34a;
  border: none;
  color: #fff;
  padding: 5px 10px;
  border-radius: 6px;
  cursor: pointer;
}

.progress-bar {
  height: 10px;
  background: #eee;
  border-radius: 6px;
  margin-top: 10px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: #2563eb;
  transition: width 0.3s;
}

.progress-text {
  font-size: 12px;
  text-align: right;
  margin-top: 5px;
  color: 555;
}

/* Calculator */
.calculator-container {
  max-width: 360px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.calculator-display {
  background: #f4f4f4;
  padding: 15px;
  border-radius: 8px;
  font-size: 24px;
  text-align: right;
  margin-bottom: 15px;
  overflow-x: auto;
}

.calculator-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.calculator-buttons button {
  padding: 20px;
  font-size: 18px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  background: #f1f1f1;
  transition: 0.2s;
}

.calculator-buttons button:hover {
  background: #ddd;
}

.calculator-buttons .operator {
  background: #2563eb;
  color: #fff;
}

.calculator-buttons .equals {
  background: #16a34a;
  color: #fff;
}

.calculator-buttons .clear {
  background: #ff4d4d;
  color: #fff;
}

.calculator-buttons .zero {
  grid-column: span 4;
}

/* Conversion */
.conv-container {
  max-width: 400px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.conv-inputs {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 20px;
}

.conv-inputs input, .conv-inputs select {
  flex: 1;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 6px;
}

.conv-inputs button {
  background: #2563eb;
  border: none;
  color: #fff;
  padding: 10px 15px;
  border-radius: 6px;
  cursor: pointer;
}

.conv-result {
  font-size: 16px;
  font-weight: bold;
  text-align: center;
  color: #2563eb;
}

/* Timer Section */
.timer-container {
  max-width: 500px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  text-align: center;
  display: none;
}

.tab-buttons {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 15px;
}

.tab-buttons button {
  padding: 8px 16px;
  border: 1px solid #ddd;
  background: #f4f4f4;
  cursor: pointer;
  border-radius: 6px;
}

.tab-buttons button.active {
  background: #2563eb;
  color: #fff;
}

.timer-display {
  font-size: 48px;
  font-weight: bold;
  margin-bottom: 15px;
}

.controls {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 20px;
}

.controls button {
  padding: 10px 20px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

#startBtn {
  background: #2563eb;
  color: #fff;
}

#stopBtn {
  background: #ff4d4d;
  color: #fff;
}

#resetBtn {
  background: #16a34a;
  color: #fff;
}

.timer-progress-bar {
  height: 10px;
  background: #eee;
  border-radius: 6px;
  margin-bottom: 20px;
  overflow: hidden;
}

.timer-progress-fill {
  height: 100%;
  width: 0%;
  background: #2563eb;
  transition: width 0.3s;
}

.set-timer input {
  width: 60px;
  margin: 0 5px;
  padding: 5px;
}

.presets {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 10px;
}

.presets button {
  padding: 6px 12px;
  border: 1px solid #ddd;
  border-radius: 6px;
  cursor: pointer;
}

.presets button:hover {
  background: #2563eb;
  color: #fff;
}

/* Strategy Timer */
.strategy-container {
  max-width: 600px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.strategy-options {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.strategy {
  flex: 1;
  padding: 1rem;
  border: 2px solid #ddd;
  border-radius: 10px;
  background: #fff;
  cursor: pointer;
  transition: all 0.3s ease;
  text-align: left;
}

.strategy h3 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.strategy p {
  margin: 0;
  font-size: 0.9rem;
  color: #666;
}

.strategy.active {
  border-color: #3b82f6;
  box-shadow: 0 0 8px rgba(59, 130, 246, 0.3);
}

.timer-box {
  background: #fff;
  padding: 1.5rem;
  border-radius: 12px;
  border: 1px solid #eee;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.05);
  margin-bottom: 1.5rem;
  text-align: center;
}

#phaseLabel {
  font-size: 1.2rem;
  margin-bottom: 1rem;
  font-weight: 600;
}

.big-time {
  font-size: 3rem;
  font-weight: bold;
  margin: 0.5rem 0 1rem;
}

.strategy-progress {
  height: 8px;
  background: #eee;
  border-radius: 5px;
  overflow: hidden;
  margin-bottom: 1rem;
}

#strategyProgress {
  height: 8px;
  width: 0%;
  background: #3b82f6;
  transition: width 0.3s ease;
}

.strategy-controls {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.strategy-controls button {
  padding: 0.5rem 1.2rem;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  transition: background 0.3s ease;
}

#strategyStartBtn {
  background: #3b82f6;
  color: #fff;
}

#strategyStartBtn:hover {
  background: #2563eb;
}

#strategyResetBtn {
  background: #f3f4f6;
}

#strategyResetBtn:hover {
  background: #e5e7eb;
}

.stats {
  display: flex;
  justify-content: space-around;
  margin-top: 1rem;
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

.stats p {
  margin: 0;
}

#completedCycles {
  color: #3b82f6;
  font-weight: bold;
}

#workSessions {
  color: #10b981;
  font-weight: bold;
}

.strategy-info {
  background: #fff;
  padding: 1rem;
  border-radius: 10px;
  border: 1px solid #eee;
}

.strategy-info h3 {
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.strategy-info p {
  font-size: 0.95rem;
  color: #444;
}

/* Notes */
.notes-container {
  max-width: 800px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.notes-actions {
  margin: 15px 0;
  display: flex;
  gap: 10px;
  align-items: center;
}

.upload-label {
  padding: 8px 12px;
  background: #4CAF50;
  color: white;
  border-radius: 5px;
  cursor: pointer;
}

#downloadPdfBtn {
  padding: 8px 12px;
  background: #2196F3;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
}

.pdf-viewer {
  margin-top: 20px;
  border: 1px solid #ccc;
  min-height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Quote Generator */
.quote-container {
  max-width: 700px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
  text-align: center;
}

.quote-text {
  font-size: 24px;
  font-style: italic;
  margin-bottom: 15px;
  color: #333;
}

.quote-author {
  font-size: 18px;
  font-weight: 600;
  color: #4a6cf7;
  margin-bottom: 20px;
}

.quote-controls {
  display: flex;
  justify-content: center;
  gap: 15px;
  margin-bottom: 30px;
}

.quote-controls button {
  padding: 12px 20px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 500;
}

.quote-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  text-align: center;
}

.stat-box {
  background-color: #f8f9fa;
  padding: 20px;
  border-radius: 8px;
}

.stat-number {
  font-size: 32px;
  font-weight: 700;
  color: #4a6cf7;
}

/* Calendar */
.calendar-container {
  max-width: 800px;
  margin: 30px auto;
  background: #fff;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  display: none;
}

.calendar {
  background-color: #fff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  margin-bottom: 20px;
}

.calendar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 20px;
  background-color: #4a6cf7;
  color: white;
}

.calendar-nav {
  display: flex;
  gap: 15px;
}

.calendar-nav button {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  color: white;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.3s;
}

.calendar-nav button:hover {
  background: rgba(255, 255, 255, 0.3);
}

.calendar-title {
  font-size: 18px;
  font-weight: 600;
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 1px;
  background-color: #ddd;
}

.calendar-cell {
  background-color: white;
  padding: 10px;
  min-height: 80px;
  position: relative;
  transition: background 0.2s;
}

.calendar-cell:hover {
  background-color: #f8f9fa;
}

.calendar-cell.header {
  background-color: #f8f9fa;
  font-weight: 600;
  text-align: center;
  min-height: auto;
  padding: 12px 10px;
}

.calendar-cell.today {
  background-color: #e6f0ff;
}

.calendar-cell.today .date-number {
  font-weight: bold;
  color: #4a6cf7;
}

.calendar-cell.selected {
  background-color: #4a6cf7;
  color: white;
}

.calendar-cell.selected .date-number {
  color: white;
}

.date-number {
  font-size: 16px;
  font-weight: 500;
}

.reminder-indicator {
  position: absolute;
  bottom: 5px;
  right: 5px;
  font-size: 10px;
  background: #ff4757;
  color: white;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.reminder-form {
  margin-top: 20px;
  padding: 20px;
  background-color: #f8f9fa;
  border-radius: 8px;
}

.reminder-form h3 {
  margin-bottom: 15px;
  color: #333;
}

.reminder-form input, 
.reminder-form textarea {
  width: 100%;
  padding: 10px;
  margin-bottom: 15px;
  border: 1px solid #ddd;
  border-radius: 6px;
  font-family: inherit;
}

.reminder-form button {
  background: #4a6cf7;
  color: white;
  border: none;
  padding: 10px 20px;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 500;
  transition: background 0.3s;
}

.reminder-form button:hover {
  background: #3b5be0;
}

.reminder-list {
  margin-top: 20px;
}

.reminder-item {
  padding: 15px;
  background-color: white;
  border-radius: 8px;
  margin-bottom: 10px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  position: relative;
}

.reminder-item h4 {
  margin: 0 0 8px 0;
  color: #333;
}

.reminder-item p {
  margin: 0;
  color: #666;
}

.delete-reminder {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #ff4757;
  color: white;
  border: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 12px;
  transition: background 0.3s;
}

.delete-reminder:hover {
  background: #ff3742;
}

.empty-state {
  text-align: center;
  padding: 20px;
  color: #888;
}

/* Responsive Design */
@media (max-width: 768px) {
  .menu {
    flex-direction: column;
    align-items: center;
  }
  
  .tools {
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    padding: 20px;
  }
  
  .strategy-options {
    flex-direction: column;
  }
  
  .quote-stats {
    grid-template-columns: 1fr;
  }
  
  .navbar {
    flex-direction: column;
    gap: 10px;
    padding: 15px;
  }
  
  .calendar-cell {
    min-height: 60px;
    padding: 8px 5px;
  }
  
  .date-number {
    font-size: 14px;
  }
  
  .reminder-indicator {
    width: 16px;
    height: 16px;
    font-size: 9px;
  }
}