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

:root {
    --bg-primary: #0a1628;
    --bg-secondary: #122035;
    --bg-card: #1a2942;
    --accent-primary: #06b6d4;
    --accent-secondary: #22d3ee;
    --accent-hover: #67e8f9;
    --accent-glow: rgba(6, 182, 212, 0.4);
    --gradient-start: #06b6d4;
    --gradient-end: #10b981;
    --text-primary: #ffffff;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border-color: #2d4a5e;
    --success-color: #10b981;
    --danger-color: #f43f5e;
    --danger-hover: #e11d48;
    --warning-color: #fbbf24;
    --input-bg: #0d1b2a;
    --shadow-lg: 0 25px 50px -12px rgba(0, 0, 0, 0.6);
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #0a1628 0%, #1e3a5f 25%, #0d2847 50%, #134e4a 75%, #0a1628 100%);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    color: var(--text-primary);
}

@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }

    50% {
        background-position: 100% 50%;
    }

    100% {
        background-position: 0% 50%;
    }
}

.app-container {
    width: 100%;
    max-width: 700px;
    animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.todo-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 32px;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.todo-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--gradient-start), var(--accent-secondary), var(--gradient-end), var(--accent-secondary), var(--gradient-start));
    background-size: 300% 100%;
    animation: shimmer 4s infinite linear;
}

@keyframes shimmer {
    0% {
        background-position: 200% 0;
    }

    100% {
        background-position: -200% 0;
    }
}

.todo-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
    letter-spacing: -0.5px;
}

.author-name {
    text-align: center;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 24px;
    background: linear-gradient(90deg, var(--accent-primary), var(--gradient-end), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.todo-form {
    margin-bottom: 20px;
}

.input-group {
    display: flex;
    gap: 12px;
    align-items: center;
}

.todo-input,
.date-input {
    padding: 14px 18px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    background: var(--input-bg);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: inherit;
    transition: all var(--transition-fast);
}

.todo-input {
    flex: 1;
    min-width: 0;
}

.todo-input:focus,
.date-input:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 4px var(--accent-glow);
}

.todo-input::placeholder {
    color: var(--text-muted);
}

.date-input {
    width: 160px;
    cursor: pointer;
}

.date-input::-webkit-calendar-picker-indicator {
    filter: invert(1);
    opacity: 0.6;
    cursor: pointer;
}

.add-btn {
    width: 52px;
    height: 52px;
    border: none;
    border-radius: 12px;
    background: var(--accent-primary);
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    flex-shrink: 0;
}

.add-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px var(--accent-glow);
}

.add-btn:active {
    transform: translateY(0);
}

.plus-icon {
    line-height: 1;
}

.error-message {
    color: var(--danger-color);
    font-size: 0.85rem;
    margin-top: 10px;
    min-height: 20px;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.error-message.visible {
    opacity: 1;
}

.controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    gap: 16px;
}

.filter-container {
    position: relative;
}

.filter-select {
    padding: 12px 40px 12px 18px;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    background: var(--input-bg);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    appearance: none;
    transition: all var(--transition-fast);
    letter-spacing: 0.5px;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2394a3b8' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
}

.filter-select:hover {
    border-color: var(--accent-primary);
}

.filter-select:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 4px var(--accent-glow);
}

.delete-all-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 10px;
    background: var(--accent-primary);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    letter-spacing: 0.5px;
}

.delete-all-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px var(--accent-glow);
}

.delete-all-btn:active {
    transform: translateY(0);
}

.todo-table-container {
    border-radius: 12px;
    overflow: hidden;
    border: 2px solid var(--border-color);
    background: var(--bg-secondary);
}

.todo-table {
    width: 100%;
    border-collapse: collapse;
}

.todo-table thead {
    background: var(--bg-card);
}

.todo-table th {
    padding: 16px;
    text-align: left;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    letter-spacing: 1px;
    text-transform: uppercase;
    border-bottom: 2px solid var(--border-color);
}

.todo-table th:last-child {
    text-align: center;
}

.todo-table td {
    padding: 16px;
    font-size: 0.9rem;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-color);
    vertical-align: middle;
}

.todo-table td:last-child {
    text-align: center;
}

.todo-table tbody tr {
    transition: background var(--transition-fast);
}

.todo-table tbody tr:hover {
    background: rgba(124, 58, 237, 0.08);
}

.todo-table tbody tr:last-child td {
    border-bottom: none;
}

.task-text {
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.task-text.completed {
    text-decoration: line-through;
    color: var(--text-muted);
}

.due-date {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.status-badge {
    display: inline-block;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-badge.pending {
    background: rgba(245, 158, 11, 0.15);
    color: var(--warning-color);
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.status-badge.completed {
    background: rgba(16, 185, 129, 0.15);
    color: var(--success-color);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.action-buttons {
    display: flex;
    gap: 8px;
    justify-content: center;
}

.action-btn {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    font-size: 1rem;
}

.complete-btn {
    background: rgba(16, 185, 129, 0.15);
    color: var(--success-color);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.complete-btn:hover {
    background: var(--success-color);
    color: var(--text-primary);
    transform: scale(1.1);
}

.delete-btn {
    background: rgba(239, 68, 68, 0.15);
    color: var(--danger-color);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

.delete-btn:hover {
    background: var(--danger-color);
    color: var(--text-primary);
    transform: scale(1.1);
}

.empty-state {
    text-align: center;
    padding: 48px 20px;
    color: var(--text-muted);
    font-size: 0.95rem;
}

.empty-state.hidden {
    display: none;
}

.todo-table.hidden {
    display: none;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.todo-table tbody tr {
    animation: slideIn 0.3s ease-out;
}

@keyframes shake {

    0%,
    100% {
        transform: translateX(0);
    }

    20%,
    60% {
        transform: translateX(-5px);
    }

    40%,
    80% {
        transform: translateX(5px);
    }
}

.shake {
    animation: shake 0.4s ease;
}

@media (max-width: 600px) {
    .todo-card {
        padding: 20px;
        border-radius: 16px;
    }

    .todo-title {
        font-size: 1.5rem;
        margin-bottom: 20px;
    }

    .input-group {
        flex-wrap: wrap;
    }

    .todo-input {
        width: 100%;
        order: 1;
    }

    .date-input {
        flex: 1;
        order: 2;
    }

    .add-btn {
        order: 3;
        width: 48px;
        height: 48px;
    }

    .controls {
        flex-direction: column;
        gap: 12px;
    }

    .filter-select,
    .delete-all-btn {
        width: 100%;
    }

    .todo-table th,
    .todo-table td {
        padding: 12px 8px;
        font-size: 0.8rem;
    }

    .task-text {
        max-width: 100px;
    }

    .action-btn {
        width: 32px;
        height: 32px;
    }

    .status-badge {
        padding: 4px 10px;
        font-size: 0.7rem;
    }
}

@media (max-width: 400px) {
    body {
        padding: 10px;
    }

    .todo-card {
        padding: 16px;
    }

    .todo-table th:nth-child(2),
    .todo-table td:nth-child(2) {
        display: none;
    }
}