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

:root {
  --primary: #667eea;
  --primary-dark: #5a6fd6;
  --danger: #ff6b6b;
  --danger-dark: #e55555;
  --success: #6bcb77;
  --warning: #ffd93d;
  --bg: #f5f7fa;
  --card-bg: #fff;
  --text: #333;
  --text-muted: #888;
  --border: #e0e0e0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

header {
  background: var(--primary);
  color: white;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

header h1 {
  font-size: 20px;
  font-weight: 600;
}

main {
  max-width: 800px;
  margin: 0 auto;
  padding: 24px;
}

section {
  background: var(--card-bg);
  border-radius: 8px;
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

section h2 {
  font-size: 18px;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text);
}

.form-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.form-row .form-group {
  flex: 1;
  min-width: 120px;
}

input[type="text"],
input[type="date"],
textarea,
select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="text"]:focus,
input[type="date"]:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

input[type="color"] {
  width: 50px;
  height: 36px;
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
}

.checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 13px;
  margin-left: 8px;
  cursor: pointer;
}

.checkbox-label input {
  width: auto;
}

.form-actions {
  display: flex;
  gap: 12px;
  margin-top: 20px;
}

.btn {
  padding: 10px 20px;
  border: none;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s, transform 0.1s;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--primary);
  color: white;
}

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

.btn-secondary {
  background: var(--border);
  color: var(--text);
}

.btn-secondary:hover {
  background: #d0d0d0;
}

.btn-danger {
  background: var(--danger);
  color: white;
}

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

.btn-small {
  padding: 6px 12px;
  font-size: 12px;
}

.task-list {
  min-height: 100px;
}

.loading {
  text-align: center;
  color: var(--text-muted);
  padding: 40px;
}

.empty-state {
  text-align: center;
  color: var(--text-muted);
  padding: 40px;
}

.task-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 12px;
  background: white;
  transition: box-shadow 0.2s;
}

.task-item:hover {
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.task-item.dragging {
  opacity: 0.5;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.drag-handle {
  cursor: grab;
  color: var(--text-muted);
  padding: 4px;
  font-size: 16px;
}

.drag-handle:active {
  cursor: grabbing;
}

.priority-badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.priority-badge.priority-1 {
  background: #ffe0e0;
  color: #cc4444;
}

.priority-badge.priority-2 {
  background: #fff8dc;
  color: #cc9900;
}

.priority-badge.priority-3 {
  background: #e0f5e0;
  color: #449944;
}

.task-content {
  flex: 1;
  min-width: 0;
}

.task-title {
  font-weight: 600;
  margin-bottom: 4px;
  word-break: break-word;
}

.task-meta {
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.task-meta .overdue {
  color: var(--danger);
  font-weight: 500;
}

.task-memo {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 6px;
  white-space: pre-wrap;
  word-break: break-word;
}

.task-actions {
  display: flex;
  gap: 8px;
  flex-shrink: 0;
}

.color-indicator {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  display: inline-block;
  vertical-align: middle;
  margin-right: 4px;
}

.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: #333;
  color: white;
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 14px;
  opacity: 0;
  transition: transform 0.3s, opacity 0.3s;
  z-index: 1000;
}

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

.toast.error {
  background: var(--danger);
}

.toast.success {
  background: var(--success);
}

@media (max-width: 600px) {
  main {
    padding: 16px;
  }

  section {
    padding: 16px;
  }

  .form-row {
    flex-direction: column;
    gap: 0;
  }

  .task-item {
    flex-direction: column;
    gap: 8px;
  }

  .task-actions {
    width: 100%;
    justify-content: flex-end;
  }
}

.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 2000;
  align-items: center;
  justify-content: center;
}

.modal.show {
  display: flex;
}

.modal-content {
  background: white;
  padding: 32px;
  border-radius: 12px;
  width: 90%;
  max-width: 360px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.modal-content h2 {
  margin-bottom: 24px;
  text-align: center;
  border: none;
  padding: 0;
}

.modal-content input[type="password"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
}

.modal-content input[type="password"]:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}