/* ==============================================
   THIS IS THE GLOBAL STYLES & RESET AREA
   ============================================== */

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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.4);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* ==============================================
   THIS IS THE HEADER AREA
   ============================================== */

.app-header {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: var(--shadow);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-stats {
    display: flex;
    gap: 30px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 10px 20px;
    background: var(--bg-tertiary);
    border-radius: 8px;
}

.stat-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

/* ==============================================
   THIS IS THE MAIN CONTENT AREA
   ============================================== */

.main-content {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
}

/* ==============================================
   THIS IS THE TASK INPUT SECTION
   ============================================== */

.task-input-section {
    margin-bottom: 30px;
}

.input-container {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.task-input {
    flex: 1;
    min-width: 250px;
    padding: 15px 20px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.task-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.priority-select {
    padding: 15px 20px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.priority-select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.add-btn {
    padding: 15px 30px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border: none;
    border-radius: 8px;
    color: white;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 10px;
}

.add-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

/* ==============================================
   THIS IS THE FILTER SECTION
   ============================================== */

.filter-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--border-color);
    flex-wrap: wrap;
    gap: 15px;
}

.filter-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 10px 20px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.filter-btn:hover {
    border-color: var(--primary-color);
    color: var(--text-primary);
}

.filter-btn.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

.sort-controls {
    display: flex;
    gap: 10px;
    align-items: center;
}

.sort-select {
    padding: 10px 15px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.95rem;
    cursor: pointer;
}

.clear-btn {
    padding: 10px 20px;
    background: var(--danger-color);
    border: none;
    border-radius: 8px;
    color: white;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.clear-btn:hover {
    background: #dc2626;
    transform: translateY(-2px);
}

/* ==============================================
   THIS IS THE TASKS LIST AREA
   ============================================== */

.tasks-section {
    min-height: 300px;
}

.tasks-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.task-item {
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
    transition: all 0.3s ease;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.task-item:hover {
    border-color: var(--primary-color);
    transform: translateX(5px);
}

.task-item.completed {
    opacity: 0.6;
}

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

.task-checkbox {
    width: 24px;
    height: 24px;
    cursor: pointer;
    accent-color: var(--success-color);
}

.priority-badge {
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.priority-badge.high {
    background: rgba(239, 68, 68, 0.2);
    color: var(--danger-color);
}

.priority-badge.medium {
    background: rgba(245, 158, 11, 0.2);
    color: var(--warning-color);
}

.priority-badge.low {
    background: rgba(16, 185, 129, 0.2);
    color: var(--success-color);
}

.task-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.task-text {
    font-size: 1.1rem;
    color: var(--text-primary);
}

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

.task-actions {
    display: flex;
    gap: 10px;
}

.action-btn {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.edit-btn {
    background: var(--primary-color);
    color: white;
}

.edit-btn:hover {
    background: var(--primary-dark);
    transform: scale(1.1);
}

.delete-btn {
    background: var(--danger-color);
    color: white;
}

.delete-btn:hover {
    background: #dc2626;
    transform: scale(1.1);
}

/* ==============================================
   THIS IS THE EMPTY STATE AREA
   ============================================== */

.empty-state {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-state.show {
    display: flex;
}

.empty-state i {
    font-size: 4rem;
    margin-bottom: 20px;
    opacity: 0.5;
}

.empty-state p {
    font-size: 1.2rem;
}

/* ==============================================
   THIS IS THE MODAL AREA
   ============================================== */

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.modal.show {
    display: flex;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.modal-content {
    background: var(--bg-secondary);
    border-radius: 12px;
    width: 90%;
    max-width: 500px;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 30px;
    border-bottom: 2px solid var(--border-color);
}

.modal-header h2 {
    color: var(--text-primary);
}

.close-modal {
    width: 36px;
    height: 36px;
    border: none;
    background: var(--bg-tertiary);
    border-radius: 6px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.3s ease;
}

.close-modal:hover {
    background: var(--danger-color);
    transform: rotate(90deg);
}

.modal-body {
    padding: 30px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    padding: 20px 30px;
    border-top: 2px solid var(--border-color);
}

.cancel-btn {
    padding: 10px 20px;
    background: var(--bg-tertiary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.3s ease;
}

.cancel-btn:hover {
    background: var(--bg-primary);
}

.save-btn {
    padding: 10px 20px;
    background: var(--success-color);
    border: none;
    border-radius: 8px;
    color: white;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.save-btn:hover {
    background: #059669;
}

/* ==============================================
   THIS IS THE FOOTER AREA
   ============================================== */

.app-footer {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 20px 30px;
    text-align: center;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.app-footer p {
    color: var(--text-secondary);
}

.app-footer i.fa-heart {
    color: var(--danger-color);
}

.back-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.back-link:hover {
    color: var(--secondary-color);
    transform: translateX(-5px);
}

/* ==============================================
   THIS IS THE RESPONSIVE DESIGN AREA
   ============================================== */

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }

    .logo {
        flex-direction: column;
    }

    .header-stats {
        width: 100%;
        justify-content: space-around;
    }

    .input-container {
        flex-direction: column;
    }

    .task-input,
    .priority-select,
    .add-btn {
        width: 100%;
    }

    .filter-section {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-buttons {
        justify-content: center;
    }

    .sort-controls {
        flex-direction: column;
        width: 100%;
    }

    .sort-select,
    .clear-btn {
        width: 100%;
    }

    .task-item {
        flex-wrap: wrap;
    }

    .app-footer {
        flex-direction: column;
        text-align: center;
    }
}