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

body {
    background: #0f172a;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    overflow: hidden;
}

/* Background Shapes */
.background-circles .circle {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
}

.circle:nth-child(1) {
    width: 300px;
    height: 300px;
    background: linear-gradient(#7c3aed, #db2777);
    top: 10%;
    left: 20%;
}

.circle:nth-child(2) {
    width: 250px;
    height: 250px;
    background: linear-gradient(#06b6d4, #3b82f6);
    bottom: 10%;
    right: 20%;
}

/* Glassmorphism Container */
.todo-app {
    width: 100%;
    max-width: 450px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(15px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    z-index: 10;
}

h2 {
    color: #fff;
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 25px;
}

.input-row {
    display: flex;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 30px;
    padding-left: 20px;
    margin-bottom: 25px;
}

input {
    flex: 1;
    border: none;
    outline: none;
    background: transparent;
    padding: 15px 0;
    color: #fff;
    font-size: 16px;
}

button {
    border: none;
    outline: none;
    padding: 15px 35px;
    background: #7c3aed;
    color: #fff;
    font-size: 16px;
    cursor: pointer;
    border-radius: 30px;
    transition: 0.3s;
}

button:hover {
    background: #6d28d9;
}

/* Task List Styles */
ul li {
    list-style: none;
    font-size: 17px;
    padding: 12px 8px 12px 50px;
    user-select: none;
    cursor: pointer;
    position: relative;
    color: #e2e8f0;
    transition: 0.2s;
}

ul li::before {
    content: '';
    position: absolute;
    height: 24px;
    width: 24px;
    border-radius: 50%;
    border: 2px solid #7c3aed;
    left: 10px;
    top: 12px;
}

ul li.checked {
    color: #94a3b8;
    text-decoration: line-through;
}

ul li.checked::before {
    background: #7c3aed;
    border: none;
}

/* Delete Button (X) */
ul li span {
    position: absolute;
    right: 0;
    top: 5px;
    width: 40px;
    height: 40px;
    font-size: 22px;
    color: #ef4444;
    line-height: 40px;
    text-align: center;
    border-radius: 50%;
}

ul li span:hover {
    background: rgba(239, 68, 68, 0.1);
}