* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
body { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); min-height: 100vh; display: flex; justify-content: center; align-items: center; }
.app-container { background: white; width: 100%; max-width: 450px; padding: 30px; border-radius: 15px; box-shadow: 0 10px 20px rgba(0,0,0,0.2); }
h1 { text-align: center; color: #333; margin-bottom: 20px; font-size: 24px; }
.input-section { display: flex; gap: 10px; margin-bottom: 20px; }
input { flex: 1; padding: 10px 15px; border: 1px solid #ccc; border-radius: 8px; outline: none; font-size: 14px; }
button { padding: 10px 20px; background: #764ba2; color: white; border: none; border-radius: 8px; cursor: pointer; transition: 0.3s; font-weight: bold; }
button:hover { background: #5a377d; }
ul { list-style: none; }
li { background: #f9f9f9; padding: 15px; border-radius: 8px; margin-bottom: 10px; display: flex; justify-content: space-between; align-items: center; border-left: 5px solid #764ba2; transition: 0.3s; }
li.completed { opacity: 0.6; border-left-color: #4caf50; }
li.completed .task-text { text-decoration: line-through; }
.delete-btn { background: #ff4757; padding: 5px 12px; font-size: 12px; border-radius: 5px; }
.delete-btn:hover { background: #ff1e34; }
.task-text { cursor: pointer; flex: 1; user-select: none; }