* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
}

html {
    font-size: 62.5%;
}

body {
    min-height: 100vh;
}

#container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: #f5f7fb;
    padding: 2rem 1.5rem;
    gap: 2rem;
}

.warn_msg {
    color: red;
    font-size: 1.4rem;
    letter-spacing: 0.05rem;
    text-align: center;
}

.todo_container {
    width: 100%;
    max-width: 72rem;
    background-color: white;
    padding: 2rem;
    border-radius: 1.5rem;
    box-shadow: 0 0 10px rgba(0,0,0,0.05);
}

.todo_container form {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

form input {
    flex: 1;
    min-width: 18rem;
    padding: 0.8rem 1rem;
    border: 1px solid #ccc;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
    font-size: 1.6rem;
}

form input:focus {
    outline: none;
    border-color: #2563eb;
}

form button {
    background-color: #2563eb;
    color: white;
    padding: 0.8rem 2rem;
    border-radius: 0.5rem;
    border: none;
    font-size: 1.6rem;
    cursor: pointer;
}

ul {
    list-style-type: none;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 2rem;
}

ul li {
    background-color: #f5f7fb;
    padding: 1rem;
    border-radius: 0.7rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

ul li span {
    font-size: 1.6rem;
    flex: 1;
    word-break: break-word; 
}

ul li span.complete {
    text-decoration: line-through;
    color: gray;
}

ul li .btns {
    display: flex;
    gap: 1rem;
}

.btns img {
    width: 2.2rem;
    height: 2.2rem;
    border: 1px solid black;
    border-radius: 50%;
    padding: 0.3rem;
    cursor: pointer;
}

@media (max-width: 480px) {
    html {
        font-size: 55%;
    }

    .todo_container {
        padding: 1.5rem;
    }

    .todo_container form {
        flex-direction: column;
    }

    form button {
        width: 100%;
    }

    ul li {
        flex-direction: column;
        align-items: flex-start;
    }

    ul li .btns {
        align-self: flex-end;
    }
}

/* Medium devices (tablets) */
@media (max-width: 768px) {
    html {
        font-size: 58%;
    }

    .todo_container {
        max-width: 90%;
    }
}