* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    padding: 1rem;
    min-height: 100vh;
    color: #e2e8f0;
}

.container {
    max-width: 60rem;
    margin: 0 auto;
    background: rgba(15, 23, 42, 0.7);
    backdrop-filter: blur(1rem);
    border-radius: 1.6rem;
    box-shadow: 0 0.8rem 3.2rem rgba(2, 8, 20, 0.4);
    padding: 1.5rem;
    border: 1px solid rgba(94, 234, 212, 0.1);
}

h1 {
    color: #5eead4;
    margin-bottom: 1.2rem;
    text-align: center;
    font-size: 2em;
    text-shadow: 0 0 1rem rgba(94, 234, 212, 0.3);
}

.input-group {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.2rem;
}

input[type="text"] {
    flex: 1;
    padding: 0.6rem 0.8rem;
    background: rgba(15, 23, 42, 0.5);
    border: 2px solid #334155;
    border-radius: 0.8rem;
    font-size: 1rem;
    transition: all 0.3s;
    color: #f1f5f9;
}

input[type="text"]:focus {
    outline: none;
    border-color: #5eead4;
    box-shadow: 0 0 0 0.3rem rgba(94, 234, 212, 0.2);
}

input[type="text"]::placeholder {
    color: #94a3b8;
}

button {
    padding: 0.5rem 0.5rem;
    background: linear-gradient(to right, #0ea5e9, #5eead4);
    color: #0f172a;
    border: none;
    border-radius: 0.8rem;
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 0.4rem 0.6rem rgba(0, 0, 0, 0.1);
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 0.6rem 0.8rem rgba(0, 0, 0, 0.15);
}

button:active {
    transform: translateY(0);
}

.filters {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.2rem;
    justify-content: center;
}

.filter-btn {
    padding: 0.4rem 0.8rem;
    background: rgba(15, 23, 42, 0.5);
    color: #cbd5e1;
    border: 1px solid #334155;
    border-radius: 0.8rem;
    cursor: pointer;
    transition: all 0.3s;
}

.filter-btn.active {
    background: linear-gradient(to right, #0ea5e9, #5eead4);
    color: #0f172a;
    border-color: transparent;
    font-weight: 600;
}

.filter-btn:hover:not(.active) {
    background: rgba(30, 41, 59, 0.7);
}

ul {
    list-style: none;
}

li {
    display: flex;
    align-items: center;
    padding: 0.8rem;
    background: rgba(15, 23, 42, 0.5);
    border-radius: 0.8rem;
    margin-bottom: 1.2rem;
    transition: all 0.3s;
    border: 1px solid rgba(94, 234, 212, 0.1);
}

li:hover {
    background: rgba(30, 41, 59, 0.7);
    transform: translateX(5px);
}

li.completed {
    opacity: 0.6;
}

li.completed span {
    text-decoration: line-through;
    color: #94a3b8;
}

.checkbox-wrapper {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    flex: 1;
}

input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    cursor: pointer;
    accent-color: #5eead4;
}

.note-text {
    flex: 1;
    font-size: 1rem;
    color: #f1f5f9;
}

.delete-btn {
    padding: 0.3rem 0.6rem;
    background: rgba(239, 68, 68, 0.2);
    color: #fecaca;
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: 0.6rem;
    font-size: 0.6rem;
    cursor: pointer;
    transition: all 0.3s;
}

.delete-btn:hover {
    background: rgba(239, 68, 68, 0.3);
    transform: scale(1.05);
}

.stats {
    text-align: center;
    color: #94a3b8;
    margin-top: 1.2rem;
    font-size: 1rem;
}

.empty-state {
    text-align: center;
    padding: 2rem;
    color: #64748b;
    font-style: italic;
}

.clear-completed {
    background: linear-gradient(to right, #ef4444, #f87171);
    color: white;
    padding: 0.4rem 0.8rem;
    font-size: 1rem;
    margin-top: 1.2rem;
    width: 100%;
}

.clear-completed:hover {
    background: linear-gradient(to right, #dc2626, #ef4444);
}