:root {
    --background-color: rgb(56, 52, 52);
    --text-color: whitesmoke;
    --header-color: rgb(255, 255, 255);
    --subheader-color: rgb(173, 173, 182);
    --paragraph-color: rgb(161, 206, 196);
    --button-color: rgb(89, 177, 89);
    --item-bg-color: black;
    --item-border-color: rgb(211, 208, 12);
    --complete-color: blue;
    --remove-btn-color: rgb(248, 5, 5);
    --edit-btn-color: rgb(62, 248, 5);
}

body.light-theme {
    --background-color: rgb(255, 255, 255);
    --text-color: rgb(0, 0, 0);
    --header-color: rgb(0, 0, 0);
    --subheader-color: rgb(80, 80, 80);
    --paragraph-color: rgb(60, 60, 60);
    --button-color: rgb(0, 123, 255);
    --item-bg-color: rgb(240, 240, 240);
    --item-border-color: rgb(200, 200, 200);
    --complete-color: rgb(0, 0, 255);
    --remove-btn-color: rgb(255, 0, 0);
    --edit-btn-color: rgb(0, 255, 0);
}

* {
    padding: 0;
    text-decoration: none;
    box-sizing: border-box;
}

body {
    background-color: var(--background-color);
    margin: 0;
    font-family: Arial, sans-serif;
}

main {
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1rem;
}

.container .todos header span i {
    appearance: none;
    background: none;
    border: none;
    outline: none;
    font-size: 3rem;
    margin-bottom: 0.1rem;
    color: var(--text-color);
}

.todos {
    width: 100%;
    max-width: 770px;
    padding: 1rem;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 1rem;
}

.todos header {
    display: flex;
    align-items: center;
    flex-direction: column;
    justify-content: space-between;
    margin-bottom: 1rem;
}

.todos header h1 {
    color: var(--header-color);
    text-align: center;
    font-size: 2rem;
    font-weight: 900;
    margin: 0;
    position: relative;
}

.todos header h1::after {
    content: '';
    display: block;
    width: 50%;
    height: 2px;
    background-color: var(--header-color);
    margin: 0.5rem auto 0;
}

.container .todos header h2 {
    color: var(--subheader-color);
    font-size: 1.5rem;
    font-weight: 900;
    margin: 0.5rem 0;
}

.container .todos header p {
    color: var(--paragraph-color);
    font-size: 1rem;
    margin: 0.5rem 0;
    transition: 0.5s;
}

.todos header button {
    display: flex;
    flex-direction: row;
    color: var(--button-color);
    font-size: 1rem;
    background: none;
    border: none;
    outline: none;
    cursor: pointer;
    font-weight: 800;
    transition: 0.5s;
}

.item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.6rem;
    background-color: var(--item-bg-color);
    margin-bottom: 1rem;
    border-radius: 1rem;
    transition: 1s;
}

.item:last-of-type {
    margin-bottom: 0;
}

.item input[type="checkbox"] {
    margin-right: 1rem;
}

.item input[type="text"] {
    appearance: none;
    background: none;
    border: none;
    outline: none;
    color: var(--text-color);
    font-size: 1rem;
    flex: 1;
    margin-right: 1rem;
}

.item input[type="text"]:not(:disabled) {
    border-bottom: 2px solid var(--item-border-color);
}

.item.complete {
    opacity: 0.4;
}

.item.complete input[type="text"] {
    text-decoration: line-through;
}

.item:hover,
.item:focus-within {
    outline: 2px solid var(--item-border-color);
}

.actions button {
    color: var(--button-color);
    margin-right: 1rem;
    opacity: 0.8;
    transition: 0.2s;
    appearance: none;
    background: none;
    border: none;
    outline: none;
    cursor: pointer;
}

.actions button i {
    font-size: 1rem;
    appearance: none;
    border: none;
}

.actions button.remove-btn {
    color: var(--remove-btn-color);
}

.actions button.edit-btn {
    color: var(--edit-btn-color);
}

.actions button:hover {
    opacity: 1;
}

.actions button:last-of-type {
    margin-right: 0;
}

@media (max-width: 768px) {
    .todos header h1 {
        font-size: 1.5rem;
    }

    .container .todos header h2 {
        font-size: 1.2rem;
    }

    .container .todos header p {
        font-size: 0.9rem;
    }

    .todos header button {
        font-size: 0.9rem;
    }

    .item input[type="text"] {
        font-size: 0.9rem;
    }

    .actions button i {
        font-size: 0.9rem;
    }
}

/* Accessibility Features */
body {
    font-size: 1rem;
    line-height: 1.5;
}

.todos header h1,
.container .todos header h2,
.container .todos header p {
    font-size: 1.2rem;
}

.todos header button {
    font-size: 1rem;
}

.item input[type="text"] {
    font-size: 1rem;
}

.actions button i {
    font-size: 1rem;
}

.todos header button:focus,
.actions button:focus {
    outline: 2px solid var(--button-color);
    outline-offset: 2px;
}