/* ===== CSS Reset and Variables ===== */
:root {
    --primary-color: #4361ee;
    --primary-dark: #3a56d4;
    --secondary-color: #7209b7;
    --accent-color: #f72585;
    --success-color: #4cc9f0;
    --warning-color: #f8961e;
    --danger-color: #e63946;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --gray-light: #e9ecef;
    --gray-medium: #6c757d;
    --gray-dark: #495057;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    background-color: #fafbfc;
}

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

/* ===== Header Styles ===== */
.header {
    background: white;
    box-shadow: var(--box-shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav a {
    text-decoration: none;
    color: var(--gray-dark);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.nav a:hover, .nav a.active {
    background-color: var(--primary-color);
    color: white;
}

/* ===== Hero Section ===== */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 4rem 0;
    margin-bottom: 3rem;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin: 2rem 0;
}

.stat-item {
    background: rgba(255, 255, 255, 0.1);
    padding: 1rem;
    border-radius: var(--border-radius);
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 1.5rem;
    font-weight: 700;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: #e11574;
    transform: translateY(-2px);
}

.btn-secondary {
    background: var(--gray-light);
    color: var(--dark-color);
}

.btn-secondary:hover {
    background: var(--gray-medium);
    color: white;
}

/* ===== Features Section ===== */
.features {
    padding: 3rem 0;
}

.features h3 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    color: var(--dark-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h4 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* ===== Tasks Page Styles ===== */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.page-header h2 {
    font-size: 2rem;
    color: var(--dark-color);
}

.task-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
}

.search-box {
    display: flex;
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
}

.search-box input {
    border: none;
    padding: 0.75rem;
    outline: none;
    min-width: 250px;
}

.search-box button {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0 1rem;
    cursor: pointer;
}

select {
    padding: 0.75rem;
    border: 1px solid var(--gray-light);
    border-radius: var(--border-radius);
    background: white;
    box-shadow: var(--box-shadow);
}

.stats-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    color: var(--gray-medium);
    font-size: 0.9rem;
}

.tasks-list {
    display: grid;
    gap: 1rem;
}

.task-item {
    background: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    border-left: 4px solid var(--gray-light);
    transition: var(--transition);
}

.task-item:hover {
    transform: translateX(5px);
}

.task-item.priority-high {
    border-left-color: var(--danger-color);
}

.task-item.priority-medium {
    border-left-color: var(--warning-color);
}

.task-item.priority-low {
    border-left-color: var(--success-color);
}

.task-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.task-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.task-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    font-size: 0.9rem;
    color: var(--gray-medium);
}

.task-status {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.status-pending {
    background: #fff3cd;
    color: #856404;
}

.status-in-progress {
    background: #cce7ff;
    color: #004085;
}

.status-completed {
    background: #d4edda;
    color: #155724;
}

.task-actions {
    display: flex;
    gap: 0.5rem;
}

.action-btn {
    padding: 0.5rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: var(--transition);
}

.btn-complete {
    background: var(--success-color);
    color: white;
}

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

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

.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--gray-medium);
}

/* ===== Form Styles ===== */
.form-container {
    max-width: 600px;
    margin: 0 auto;
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.form-container h2 {
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}

.form-container p {
    margin-bottom: 2rem;
    color: var(--gray-medium);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--dark-color);
}

input, select, textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--gray-light);
    border-radius: var(--border-radius);
    font-family: inherit;
    transition: var(--transition);
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.1);
}

.error-message {
    color: var(--danger-color);
    font-size: 0.875rem;
    margin-top: 0.25rem;
    display: block;
}

.form-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    margin-top: 2rem;
}

.form-feedback {
    padding: 1rem;
    border-radius: var(--border-radius);
    margin-top: 1rem;
    text-align: center;
}

.form-feedback.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.form-feedback.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* ===== Footer Styles ===== */
.footer {
    background: var(--dark-color);
    color: white;
    padding: 2rem 0;
    margin-top: 3rem;
}

.footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer a {
    color: var(--success-color);
    text-decoration: none;
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav ul {
        gap: 1rem;
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .task-controls {
        width: 100%;
    }
    
    .search-box input {
        min-width: auto;
        flex: 1;
    }
    
    .footer .container {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-cards {
        grid-template-columns: 1fr;
    }
    
    .task-header {
        flex-direction: column;
        gap: 1rem;
    }
    
    .task-actions {
        align-self: flex-end;
    }
}