* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #3a7bd5 0%, #1a3a6b 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 620px;
    margin: 0 auto;
    background: #fff;
    border-radius: 20px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

h1 {
    background: linear-gradient(135deg, #3a7bd5 0%, #1a3a6b 100%);
    color: #fff;
    padding: 28px 30px;
    text-align: center;
    font-size: 2em;
    font-weight: 400;
    letter-spacing: 0.5px;
}

.input-section {
    padding: 24px 30px;
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

#taskInput {
    flex: 1;
    min-width: 160px;
    padding: 13px 18px;
    border: 2px solid #dde3f0;
    border-radius: 10px;
    font-size: 15px;
    transition: border-color 0.3s;
    color: #222;
}

#taskInput:focus {
    outline: none;
    border-color: #3a7bd5;
}

#categorySelect {
    padding: 13px 14px;
    border: 2px solid #dde3f0;
    border-radius: 10px;
    font-size: 14px;
    color: #333;
    background: #fff;
    cursor: pointer;
    transition: border-color 0.3s;
}

#categorySelect:focus {
    outline: none;
    border-color: #3a7bd5;
}

#addBtn {
    padding: 13px 22px;
    background: linear-gradient(135deg, #3a7bd5 0%, #1a3a6b 100%);
    color: #fff;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    cursor: pointer;
    transition: opacity 0.2s, transform 0.1s;
}

#addBtn:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.filters {
    display: flex;
    background: #f4f6fb;
    padding: 10px 20px;
    gap: 8px;
    flex-wrap: wrap;
}

.filter-btn {
    flex: 1;
    padding: 10px;
    border: none;
    background: transparent;
    border-radius: 8px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    color: #555;
    transition: all 0.25s;
    white-space: nowrap;
}

.filter-btn.active,
.filter-btn:hover {
    background: #fff;
    color: #3a7bd5;
    box-shadow: 0 2px 10px rgba(58, 123, 213, 0.15);
}

#taskList {
    list-style: none;
    max-height: 460px;
    overflow-y: auto;
}

.task-item {
    display: flex;
    align-items: center;
    padding: 16px 30px;
    border-bottom: 1px solid #f0f2f8;
    gap: 12px;
    transition: background 0.2s;
}

.task-item:hover {
    background: #f8faff;
}

.task-item.completed {
    opacity: 0.55;
}

.task-checkbox {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: #3a7bd5;
    flex-shrink: 0;
}

.task-text {
    flex: 1;
    font-size: 15px;
    color: #222;
}

.task-text.completed {
    text-decoration: line-through;
    color: #aaa;
}

.category-badge {
    font-size: 11px;
    font-weight: 600;
    padding: 3px 9px;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    flex-shrink: 0;
}

.badge-work {
    background: #e3f0ff;
    color: #1a6fd4;
}

.badge-personal {
    background: #e8f8ef;
    color: #1a8a4a;
}

.badge-study {
    background: #fff5e0;
    color: #b87700;
}

.task-actions {
    display: flex;
    gap: 6px;
}

.btn {
    width: 34px;
    height: 34px;
    border: none;
    border-radius: 7px;
    cursor: pointer;
    font-size: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.15s, box-shadow 0.15s;
}

.btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 3px 8px rgba(0,0,0,0.15);
}

.btn-edit  { background: #fff3cd; color: #856404; }
.btn-delete { background: #f8d7da; color: #721c24; }

.stats {
    padding: 18px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #f4f6fb;
    font-size: 14px;
    color: #555;
    font-weight: 500;
}

#clearCompleted {
    padding: 9px 18px;
    background: #6c757d;
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 13px;
    transition: background 0.2s;
}

#clearCompleted:hover {
    background: #545b62;
}

@media (max-width: 480px) {
    .input-section { flex-direction: column; }
    .filters { gap: 5px; }
    .filter-btn { font-size: 12px; }
}