:root {
  --primary: #004225;
  --primary-hover: #003019;
  --break: #F97316;
  --break-hover: #EA580C;
  --background: #F0FDFA;
  --surface: #FFFFFF;
  --text: #1F2937;
  --text-secondary: #6B7280;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  background-color: var(--background);
  color: var(--text);
}

.container {
  text-align: center;
  background-color: var(--surface);
  padding: 2.5rem;
  border-radius: 20px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
  width: 90%;
  max-width: 400px;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 2rem;
  color: var(--text);
}

h1 .emoji {
    margin-right: 0.5rem;
    font-size: 1.8rem;
    vertical-align: middle;
}

.timer {
  font-size: 5rem;
  font-weight: 700;
  margin: 2rem 0;
  font-variant-numeric: tabular-nums;
  color: var(--primary);
}

.controls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin: 2rem 0;
}

.controls button {
  font-size: 1rem;
  padding: 0.75rem 1.5rem;
  cursor: pointer;
  border: none;
  border-radius: 12px;
  font-weight: 600;
  transition: all 0.2s ease;
}

#start {
  background-color: var(--primary);
  color: white;
  grid-column: span 2;
}

#start:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
}

#reset {
  background-color: #F3F4F6;
  color: var(--text);
}

#reset:hover {
  background-color: #E5E7EB;
}

#toggle-mode {
  background-color: #F3F4F6;
  color: var(--text);
}

#toggle-mode:hover {
  background-color: #E5E7EB;
}

#toggle-mode.break-mode {
  background-color: var(--break);
  color: white;
}

#toggle-mode.break-mode:hover {
  background-color: var(--break-hover);
}

.mode {
  margin-top: 1.5rem;
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.settings {
    margin: 1.5rem 0;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.setting-group {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.setting-group input {
    width: 70px;
    padding: 0.5rem;
    border: 1px solid #E5E7EB;
    border-radius: 8px;
    font-size: 1rem;
    text-align: center;
}

.setting-group label {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.popup {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.popup.hidden {
    display: none;
}

.popup-content {
    background-color: var(--surface);
    padding: 2rem;
    border-radius: 16px;
    text-align: center;
    max-width: 90%;
    width: 400px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.popup-content h2 {
    margin-top: 0;
    color: var(--primary);
}

.popup-content button {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    margin-top: 1rem;
    transition: background-color 0.2s ease;
}

.popup-content button:hover {
    background-color: var(--primary-hover);
}

.todo-section {
    margin: 2rem 0;
    text-align: left;
}

.todo-section h2 {
    font-size: 1.2rem;
    color: var(--text);
    margin-bottom: 1rem;
    text-align: center;
}

.todo-inputs {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.todo-input-group {
    display: flex;
    gap: 0.5rem;
}

.todo-input {
    flex: 1;
    padding: 0.75rem;
    border: 1px solid #E5E7EB;
    border-radius: 8px;
    font-size: 0.95rem;
    transition: border-color 0.2s ease;
}

.todo-input:focus {
    outline: none;
    border-color: var(--primary);
}

.todo-input::placeholder {
    color: var(--text-secondary);
}