body {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    font-family: 'Inter', sans-serif;
    min-height: 100vh;
    padding: 40px 20px;
}

.todo-card {
    max-width: 500px;
    margin: auto;
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
}

h2 {
    font-weight: 700;
    color: #2d3748;
    letter-spacing: -0.5px;
}

.input-group {
    background: #f8fafc;
    border-radius: 12px;
    padding: 5px;
    border: 1px solid #e2e8f0;
    transition: border-color 0.2s;
}

.input-group.is-invalid {
    border-color: #dc3545;
}

.form-control {
    border: none;
    background: transparent;
    padding: 12px 15px;
}

.form-control:focus {
    box-shadow: none;
    background: transparent;
}

.btn-add {
    border-radius: 10px !important;
    font-weight: 600;
    padding: 10px 20px;
}

.todo-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px;
    margin-bottom: 10px;
    background: #fff;
    border: 1px solid #f1f5f9;
    border-radius: 12px;
    transition: all 0.2s ease;
}

.todo-item:hover {
    border-color: #cbd5e1;
    transform: translateY(-2px);
}

.todo-text {
    flex-grow: 1;
    margin-right: 15px;
    font-weight: 500;
    color: #4a5568;
    cursor: pointer;
}

.completed {
    text-decoration: line-through;
    opacity: 0.5;
}

.btn-action {
    width: 32px;
    height: 32px;
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    margin-left: 5px;
    font-size: 14px;
}

.edit-input {
    border: 1px solid #3b82f6;
    border-radius: 6px;
    padding: 2px 8px;
    width: 100%;
}

.error-msg {
    color: #dc3545;
    font-size: 0.8rem;
    margin-top: -15px;
    margin-bottom: 15px;
    display: none;
}