:root {
  --bg-color: #111827;
  --card-bg: #1f2937;
  --text-color: #f9fafb;
  --text-muted: #9ca3af;
  --accent: #3b82f6;
  --border: #374151;
  --todo: #94a3b8;
  --progress: #3b82f6;
  --review: #f59e0b;
  --done: #22c55e;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; }
body { background: var(--bg-color); color: var(--text-color); height: 100vh; display: flex; flex-direction: column; }

/* Header */
header { padding: 1rem 2rem; background: var(--card-bg); border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.5rem; font-weight: bold; color: var(--accent); }
nav { display: flex; gap: 1rem; }
.btn { padding: 0.5rem 1rem; border: none; border-radius: 0.375rem; cursor: pointer; font-weight: 500; transition: opacity 0.2s; }
.btn-primary { background: var(--accent); color: white; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
nav-btn { background: transparent; color: var(--text-muted); font-size: 1rem; }
nav-btn.active { color: var(--accent); border-bottom: 2px solid var(--accent); }
.project-select { padding: 0.5rem; background: var(--bg-color); color: var(--text-color); border: 1px solid var(--border); border-radius: 0.375rem; }

/* Main Content */
main { flex: 1; padding: 1rem; overflow-y: auto; }
.view { display: none; }
.view.active { display: block; }

/* Board View */
.board { display: flex; gap: 1rem; height: 100%; overflow-x: auto; }
.column { min-width: 280px; flex: 1; background: var(--card-bg); border-radius: 0.5rem; padding: 1rem; display: flex; flex-direction: column; }
.column-header { display: flex; justify-content: space-between; margin-bottom: 1rem; font-weight: bold; }
.column-body { flex: 1; overflow-y: auto; display: flex; flex-direction: column; gap: 0.75rem; }

/* Task Card */
.task-card { background: var(--bg-color); padding: 0.75rem; border-radius: 0.375rem; border: 1px solid var(--border); cursor: pointer; transition: transform 0.1s; }
.task-card:hover { transform: translateY(-2px); border-color: var(--accent); }
.task-title { font-weight: 500; margin-bottom: 0.5rem; }
.task-meta { display: flex; justify-content: space-between; font-size: 0.75rem; color: var(--text-muted); margin-top: 0.5rem; }
.priority-badge { padding: 0.125rem 0.375rem; border-radius: 0.25rem; font-size: 0.625rem; text-transform: uppercase; }
.priority-low { background: #1e3a8a; color: #93c5fd; }
.priority-medium { background: #1e40af; color: #bfdbfe; }
.priority-high { background: #78350f; color: #fde68a; }
.priority-critical { background: #7f1d1d; color: #fecaca; }

/* Stats View */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1rem; }
.stat-card { background: var(--card-bg); padding: 1.5rem; border-radius: 0.5rem; text-align: center; border: 1px solid var(--border); }
.stat-value { font-size: 2.5rem; font-weight: bold; color: var(--accent); }
.stat-label { color: var(--text-muted); margin-top: 0.5rem; }

/* List View */
.list-header { margin-bottom: 1rem; display: flex; gap: 0.5rem; flex-wrap: wrap; }
.search-input { padding: 0.5rem; background: var(--card-bg); color: var(--text-color); border: 1px solid var(--border); border-radius: 0.375rem; flex: 1; min-width: 200px; }
.list-table { width: 100%; border-collapse: collapse; background: var(--card-bg); border-radius: 0.5rem; overflow: hidden; }
.list-table th, .list-table td { padding: 0.75rem 1rem; text-align: left; border-bottom: 1px solid var(--border); }
.list-table th { background: var(--bg-color); color: var(--text-muted); font-weight: 600; text-transform: uppercase; font-size: 0.75rem; }
.list-table tr:hover { background: #263145; }

/* Projects View */
.projects-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 1rem; }
.project-card { background: var(--card-bg); padding: 1.5rem; border-radius: 0.5rem; border: 1px solid var(--border); cursor: pointer; transition: 0.2s; }
.project-card:hover { border-color: var(--accent); }
.project-name { font-size: 1.25rem; font-weight: bold; margin-bottom: 0.5rem; }

/* Modal */
.modal { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.7); z-index: 100; justify-content: center; align-items: center; }
.modal.active { display: flex; }
.modal-content { background: var(--card-bg); padding: 1.5rem; border-radius: 0.5rem; width: 500px; max-width: 90%; border: 1px solid var(--border); }
.modal-header { display: flex; justify-content: space-between; margin-bottom: 1rem; }
.modal-close { background: none; border: none; color: var(--text-color); font-size: 1.5rem; cursor: pointer; }
.form-group { margin-bottom: 1rem; }
.form-group label { display: block; margin-bottom: 0.25rem; color: var(--text-muted); font-size: 0.875rem; }
.form-group input, .form-group textarea, .form-group select { width: 100%; padding: 0.5rem; background: var(--bg-color); border: 1px solid var(--border); color: var(--text-color); border-radius: 0.375rem; }
.form-row { display: flex; gap: 1rem; }
.form-row .form-group { flex: 1; }
.modal-actions { display: flex; justify-content: flex-end; gap: 0.5rem; margin-top: 1.5rem; }