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HTML 

              
                <todos-app></todos-app>
!

CSS 

              
                
@danger-color: #a30000;
@primary-color: cornflowerblue;
@page-bg-color: #e2e1e0;
@todo-bg-color: #fafafa;
@todo-hover-color: #EEEEEE;
@todo-done-color: lightgray;
@todo-max-width: 450px;
@base-size: 30px;
@check-size: 24px;
@half-size: @base-size / 2;
@third-size: @base-size / 3;
@base-font: 14px;
@input-font: 21px;
@header-font: 24px;
* {
    font-family: Helvetica, sans-serif;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    background-color: @page-bg-color;
    box-shadow: inset 0px 0px 5vw 0px rgba(0, 0, 0, 0.75);
    min-height: 100vh;
}
todos-app {
    max-width: @todo-max-width;
    display: block;
    background-color: @todo-bg-color;
    margin: 35px auto;
    box-shadow: 0 14px 28px rgba(0, 0, 0, 0.25), 0 10px 10px rgba(0, 0, 0, 0.22);
    h1 {
        font-size: @header-font;
				line-height: @header-font;
        padding: @base-size @base-size @half-size;
    }
    input:not([type="checkbox"]) {
        font-size: @input-font;
        padding: @third-size;
        margin-left: @base-size - @third-size;
        width: calc(~"100% - 150px");
        @media (max-width: 419px) {
						margin-left: @base-size;
            width: calc(100% - 60px) !important;
        }
        + button {
            font-size: @input-font;
						font-weight: bold;
            letter-spacing: 1px;
            margin-left: @half-size;
            width: @base-size * 3;
            @media (max-width: 419px) {
                width: calc(100% - 60px) !important;
                margin: @third-size 0 0 @base-size !important;
            }
            padding: @third-size;
            color: @todo-bg-color;
            background-color: @primary-color;
            border: none;
            transition: all .25s ease-in-out;
            &:hover {
                box-shadow: 0 7px 14px rgba(0,0,0,0.25), 0 5px 5px rgba(0,0,0,0.22);
            }
        }
    }
    ul {
        list-style: none;
        padding-left: 0;
        padding-top: @half-size;
        li {
            position: relative;
            display: flex;
            align-items: center;
            text-align: left;
            padding: 20px @base-size;
            border-bottom: 1px dotted rgba(0, 0, 0, .25);
            font-size: @base-font;
            transition: all .3s ease-in-out;
            &:last-of-type {
                border-bottom: none;
            }
            &:hover {
                background-color: @todo-hover-color;
            }
            span, input:not([type="checkbox"]) {
                margin-right: auto;
                margin-left: @half-size;
                font-size: @input-font;
            }
            input:not([type="checkbox"]) {
                position: relative;
                margin-left: @base-size;
                border: none;
            }
            span {
                padding: @third-size;
                + button {
                    position: absolute;
                    right: @base-size;
                    width: @check-size;
                    height: @check-size;
                    line-height: @check-size;
                    background-color: @todo-bg-color;
                    border: 1px solid @todo-done-color;
                    border-radius: 50%;
                    text-align: center;
                    text-decoration: none;
                    cursor: default;
                    &:before,
                    &:after {
                        position: absolute;
                        top: 5px;
                        left: 11px;
                        content: ' ';
                        height: 13px;
                        width: 1px;
                        background-color: @todo-done-color;
                    }
                    &:hover {
                        border-color: @danger-color;
                        background-color: @danger-color;
                        color: @todo-bg-color;
                        transition: background-color .3s ease-in-out;
                        &:before,
                        &:after {
                            background-color: @todo-bg-color;
                        }
                    }
                    &:before {
                        transform: rotate(45deg);
                    }
                    &:after {
                        transform: rotate(-45deg);
                    }
                }
            }
            label {
                position: relative;
                height: @check-size;
                width: @check-size;
                &::before, &::after {
                    position: absolute;
                    content: "";
                    cursor: pointer;
                }
                /* Outside border of fake checkbox */
                &::before {
                    height: @check-size;
                    width: @check-size;
                    background-color: #FFFFFF;
                    box-shadow: 0px 0px 0px 3px rgba(0, 0, 0, 0.5);
                    left: 0px;
                    top: 0;
                    border-radius: 3px;
                }
                /* Checkmark of fake checkbox, hidden by default */
                &::after {
                    content: none;
                    height: @check-size / 4;
                    width: @check-size / 1.33;
                    border-left: 3px solid;
                    border-bottom: 3px solid;
                    transform: rotate(-45deg);
                    left: @check-size / 10;
                    top: @check-size / 4;
                }
                &:focus-within {
                    /*Adding focus styles on the outer-box of the fake checkbox*/
                    outline: rgb(59, 153, 252) auto 5px;
                }
                input[type="checkbox"] {
                    /* Hides real checkboxes, but not from the DOM */
                    position: absolute;
                    overflow: hidden;
                    clip: rect(0 0 0 0);
                    height: 1px; width: 1px;
                    margin: -1px; padding: 0; border: 0;
                }
            }
                    input:not([type="checkbox"]) {
                        width: 100%;
                        + button {
                            /* Temp hides remove button when edit input is focused */
                            position: absolute;
                            overflow: hidden;
                            clip: rect(0 0 0 0);
                            height: 1px; width: 1px;
                            margin: -1px; padding: 0; border: 0;
                        }
                    }
            &.done {
                /* Show checkmark of fake checkbox when clicked */
                > label::after {
                    content: "";
                    opacity: 1;
                    animation: fadeIn .2s ease-out forwards;
                }
                > span {
                    text-decoration: line-through;
                    color: @todo-done-color;
                    font-style: italic;
                    letter-spacing: 1px;
                }
            }
        }
    }
}

@keyframes fadeIn {
	from {
		opacity: 0;
		transform: scale(0) rotate(-45deg);
		transform-origin: center;
	}
	to {
		opacity: 1;
		transform: scale(1) rotate(-45deg);
	}
}
!

JS 

              
                // Creates a mock backend with 3 todos
import { todoFixture } from "//unpkg.com/can-demo-models@5/index.mjs";
todoFixture(3);

import { realtimeRestModel, StacheElement, type } from "//unpkg.com/can@5/everything.mjs";

const Todo = realtimeRestModel("/api/todos/{id}").Map;

class TodosApp extends StacheElement {
    static get view() {
        return `
            <h1>Today’s to-dos</h1>
            {{# if(this.todosPromise.isPending) }}
                Loading todos…
            {{/ if }}
            {{# if(this.todosPromise.isRejected) }}
                <p>Couldn’t load todos; {{ this.todosPromise.reason }}</p>
            {{/ if }}
            {{# if(this.todosPromise.isResolved) }}
                <input placeholder="What needs to be done?" value:bind="this.newName" />
                <button on:click="this.save()" type="button">Add</button>
                <ul>
                    {{# for(todo of this.todosPromise.value) }}
                        <li class="{{# if(todo.complete) }}done{{/ if }}">
                            <label>
                                <input checked:bind="todo.complete" on:change="todo.save()" type="checkbox" />
                            </label>
                            {{# eq(todo, this.selected) }}
                                <input focused:from="true" on:blur="this.saveTodo(todo)" value:bind="todo.name" />
                            {{ else }}
                                <span on:click="this.selected = todo">
                                    {{ todo.name }}
                                </span>
                            {{/ eq }}
                            <button on:click="todo.destroy()" type="button"></button>
                        </li>
                    {{/ for }}
                </ul>
            {{/ if }}
        `;
    }

    static get props() {
        return {
            newName: String,
            selected: type.maybe(Todo),

            get todosPromise() {
                return Todo.getList({sort: "name"});
            }
        };
    }

    save() {
        const todo = new Todo({name: this.newName});
        todo.save();
        this.newName = "";
    }

    saveTodo(todo) {
        todo.save();
        this.selected = null;
    }
};
customElements.define("todos-app", TodosApp);
!
999px

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