body 
{ 
    background: #2c3e50; 
    font-family: 'Segoe UI', sans-serif; 
    display: flex; 
    justify-content: center; 
    padding-top: 50px; 
    color: #333; 
}
.back-btn {
    position: fixed;
    top: 20px;
    left: 20px;
    padding: 10px 20px;
    background: #e74c3c;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 2px 8px rgba(231, 76, 60, 0.2);
    transition: all 0.2s;
    z-index: 1000;
}
.back-btn:hover { background: #c0392b; transform: translateY(-2px); }
.app-container 
{ 
    background: #ecf0f1; 
    width: 400px; 
    padding: 2rem; 
    border-radius: 10px; 
    box-shadow: 0 10px 25px rgba(0,0,0,0.3); 
}

header 
{ 
    display: flex; 
    justify-content: space-between; 
    align-items: baseline; 
    border-bottom: 2px solid #bdc3c7; 
    margin-bottom: 20px; 
    padding-bottom: 10px; 
}
h1 
{ 
    margin: 0; 
    font-size: 1.5rem; 
    color: #2c3e50; 
}
h1 span 
{ 
    color: #e74c3c; 
}
#stats 
{ 
    font-size: 0.8rem; 
    color: #7f8c8d; 
    font-weight: bold; 
}

form 
{ 
    display: flex; 
    gap: 10px; 
    margin-bottom: 20px; 
}
input 
{ 
    flex: 1; 
    padding: 10px; 
    border: 2px solid #bdc3c7; 
    border-radius: 5px; 
    outline: none; 
}
input:focus 
{ 
    border-color: #e74c3c; 
}
button 
{ 
    background: #e74c3c; 
    color: white; 
    border: none; 
    padding: 0 20px; 
    font-size: 1.5rem; 
    border-radius: 5px; 
    cursor: pointer; 
    transition: background 0.3s; 
}

ul 
{ 
    list-style: none; 
    padding: 0; 
}
li 
{ 
    background: white; 
    border-bottom: 1px solid #eee; 
    padding: 15px; 
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    transition: all 0.2s; 
}
li:first-child 
{ 
    border-top-left-radius: 5px; 
    border-top-right-radius: 5px; 
}
li:last-child 
{ 
    border-bottom-left-radius: 5px; 
    border-bottom-right-radius: 5px; 
    border-bottom: none; 
}
li.completed 
{ 
    background: #d5dbdb; 
    text-decoration: line-through; 
    color: #95a5a6; 
}

.actions button 
{ 
    font-size: 1rem; 
    padding: 5px 10px; 
    margin-left: 5px; 
    border-radius: 3px; 
}
.btn-check 
{ 
    background: #27ae60; 
}
.btn-delete 
{ 
    background: #c0392b; 
}