/* ========== CSS VARIABLES ========== */
:root {
    /* Color Palette - Monochrome */
    --color-black: #000000;
    --color-white: #ffffff;
    --color-gray-100: #f8f9fa;
    --color-gray-200: #e9ecef;
    --color-gray-300: #dee2e6;
    --color-gray-400: #ced4da;
    --color-gray-500: #adb5bd;
    --color-gray-600: #6c757d;
    --color-gray-700: #495057;
    --color-gray-800: #343a40;
    --color-gray-900: #212529;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-weight-light: 300;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-xxl: 4rem;
    
    /* Layout */
    --container-max-width: 1200px;
    --sidebar-width: 80px;
    --header-height: 70px;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* ========== RESET & BASE STYLES ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-weight: var(--font-weight-regular);
    line-height: 1.6;
    color: var(--color-gray-800);
    background-color: var(--color-gray-100);
    overflow-x: hidden;
}

.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========== HEADER ========== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-gray-200);
    z-index: 1000;
    transition: var(--transition-medium);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-black);
    letter-spacing: -0.02em;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-link {
    text-decoration: none;
    color: var(--color-gray-700);
    font-weight: var(--font-weight-medium);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    color: var(--color-black);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-black);
    transition: var(--transition-fast);
}

.nav-link:hover::after {
    width: 100%;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    gap: 4px;
}

.menu-toggle span {
    width: 25px;
    height: 2px;
    background-color: var(--color-black);
    transition: var(--transition-fast);
}

/* ========== SIDEBAR ========== */
.sidebar {
    position: fixed;
    left: 0;
    top: var(--header-height);
    width: var(--sidebar-width);
    height: calc(100vh - var(--header-height));
    background-color: var(--color-white);
    border-right: 1px solid var(--color-gray-200);
    z-index: 999;
    transition: var(--transition-medium);
}

.sidebar-content {
    padding: var(--spacing-lg) 0;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
}

.sidebar-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    color: var(--color-gray-600);
    text-decoration: none;
    border-radius: 12px;
    transition: var(--transition-fast);
    position: relative;
}

.sidebar-link:hover {
    background-color: var(--color-gray-100);
    color: var(--color-black);
    transform: translateY(-2px);
}

.sidebar-link i {
    font-size: 1.2rem;
}

/* ========== MAIN CONTENT ========== */
.main {
    margin-left: var(--sidebar-width);
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
    padding: var(--spacing-xl) 0;
}

/* ========== HERO SECTION ========== */
.hero {
    margin-bottom: var(--spacing-xxl);
}

.hero-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
    min-height: 50vh;
}

.hero-title {
    font-size: 3rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-black);
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.03em;
    line-height: 1.2;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.hero-stats {
    display: flex;
    gap: var(--spacing-xl);
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.stat-number {
    font-size: 2rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-black);
    line-height: 1;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--color-gray-600);
    font-weight: var(--font-weight-medium);
    margin-top: var(--spacing-xs);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-placeholder {
    width: 200px;
    height: 200px;
    background-color: var(--color-gray-200);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: var(--color-gray-400);
    transition: var(--transition-medium);
}

.profile-placeholder:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

.profile-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 20px;
}

/* ========== SECTION STYLES ========== */
.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xxl);
}

.section-title {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--color-black);
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-gray-600);
    max-width: 600px;
    margin: 0 auto;
}

/* ========== APPS SECTION ========== */
.apps-section {
    margin-bottom: var(--spacing-xxl);
}

.apps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-lg);
}

.app-card {
    background-color: var(--color-white);
    border-radius: 16px;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: var(--transition-medium);
    border: 1px solid var(--color-gray-200);
}

.app-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.app-icon {
    width: 64px;
    height: 64px;
    background-color: var(--color-gray-100);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-md);
}

.app-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 12px;
}

.app-title {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    color: var(--color-black);
    margin-bottom: var(--spacing-sm);
}

.app-description {
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.app-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.tag {
    background-color: var(--color-gray-100);
    color: var(--color-gray-700);
    font-size: 0.75rem;
    font-weight: var(--font-weight-medium);
    padding: 4px 8px;
    border-radius: 6px;
    transition: var(--transition-fast);
}

.tag:hover {
    background-color: var(--color-gray-200);
}

.app-links {
    display: flex;
    gap: var(--spacing-sm);
}

.app-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 8px 16px;
    border-radius: 8px;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: var(--font-weight-medium);
    transition: var(--transition-fast);
}

.app-link.primary {
    background-color: var(--color-black);
    color: var(--color-white);
}

.app-link.primary:hover {
    background-color: var(--color-gray-800);
    transform: translateY(-1px);
}

.app-link.secondary {
    background-color: var(--color-gray-100);
    color: var(--color-gray-700);
    border: 1px solid var(--color-gray-300);
}

.app-link.secondary:hover {
    background-color: var(--color-gray-200);
    transform: translateY(-1px);
}

/* Add More Apps Card */
.app-card.add-more {
    border: 2px dashed var(--color-gray-300);
    background-color: transparent;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 280px;
}

.app-card.add-more:hover {
    border-color: var(--color-gray-400);
    background-color: var(--color-gray-50);
}

.add-more-content {
    text-align: center;
    color: var(--color-gray-500);
}

.add-more-content i {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
    display: block;
}

.add-more-content span {
    font-weight: var(--font-weight-medium);
}

/* ========== CONTACT SECTION ========== */
.contact-section {
    margin-bottom: var(--spacing-xxl);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.contact-card {
    background-color: var(--color-white);
    border-radius: 16px;
    padding: var(--spacing-lg);
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-medium);
    border: 1px solid var(--color-gray-200);
}

.contact-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.contact-card i {
    font-size: 2rem;
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-md);
}

.contact-card h4 {
    font-size: 1.125rem;
    font-weight: var(--font-weight-semibold);
    color: var(--color-black);
    margin-bottom: var(--spacing-sm);
}

.contact-card p {
    color: var(--color-gray-600);
}

/* ========== FOOTER ========== */
.footer {
    background-color: var(--color-white);
    border-top: 1px solid var(--color-gray-200);
    padding: var(--spacing-lg) 0;
    margin-left: var(--sidebar-width);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: var(--color-gray-600);
}

.footer-links {
    display: flex;
    gap: var(--spacing-md);
}

.footer-links a {
    color: var(--color-gray-600);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-black);
}

/* ========== RESPONSIVE DESIGN ========== */

/* Tablet */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-lg);
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .apps-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

/* ========== MOBILE SIDEBAR ========== */
.mobile-sidebar {
    position: fixed;
    top: var(--header-height);
    left: -100%;
    width: 280px;
    height: calc(100vh - var(--header-height));
    background-color: var(--color-white);
    box-shadow: var(--shadow-lg);
    z-index: 999;
    transition: var(--transition-medium);
    overflow-y: auto;
}

.mobile-sidebar.active {
    left: 0;
}

.mobile-sidebar-content {
    padding: var(--spacing-xl) 0;
}

.mobile-nav {
    display: flex;
    flex-direction: column;
}

.mobile-nav-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-xl);
    text-decoration: none;
    color: var(--color-gray-700);
    font-weight: var(--font-weight-medium);
    font-size: 1.1rem;
    transition: var(--transition-fast);
    border-bottom: 1px solid var(--color-gray-100);
}

.mobile-nav-link:hover {
    background-color: var(--color-gray-50);
    color: var(--color-black);
}

.mobile-nav-link i {
    font-size: 1.2rem;
    width: 24px;
    text-align: center;
}

.mobile-nav-link.active {
    background-color: var(--color-gray-100);
    color: var(--color-black);
}

/* Mobile */
@media (max-width: 768px) {
    :root {
        --sidebar-width: 0;
    }
    
    .nav {
        display: none;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.active {
        transform: translateX(0);
        width: 100%;
        background-color: var(--color-white);
    }
    
    .main {
        margin-left: 0;
    }
    
    .footer {
        margin-left: 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .apps-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .profile-placeholder {
        width: 150px;
        height: 150px;
        font-size: 3rem;
    }
    
    .app-card {
        padding: var(--spacing-md);
    }
}

/* ========== ANIMATIONS ========== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.hero, .apps-section, .contact-section {
    animation: fadeInUp 0.6s ease-out;
}

.app-card, .contact-card {
    animation: fadeIn 0.5s ease-out;
}

/* ========== SCROLL BEHAVIOR ========== */
.header.scrolled {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
}

/* ========== FOCUS STYLES ========== */
a:focus,
button:focus {
    outline: 2px solid var(--color-black);
    outline-offset: 2px;
}

/* ========== SELECTION ========== */
::selection {
    background-color: var(--color-gray-800);
    color: var(--color-white);
}

/* ========== POLICY PAGES ========== */
.privacy-section,
.terms-section {
    margin-bottom: var(--spacing-xxl);
    min-height: calc(100vh - var(--header-height) - 200px);
}

.policy-content,
.terms-content {
    max-width: 800px;
    margin: 0 auto;
}

.policy-card,
.terms-card {
    background-color: var(--color-white);
    border-radius: 16px;
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-gray-200);
}

.policy-item,
.terms-item {
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-gray-200);
}

.policy-item:last-of-type,
.terms-item:last-of-type {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.policy-item h3,
.terms-item h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    color: var(--color-black);
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.01em;
}

.policy-item p,
.terms-item p {
    color: var(--color-gray-600);
    line-height: 1.7;
    margin-bottom: var(--spacing-sm);
}

.policy-item p:last-child,
.terms-item p:last-child {
    margin-bottom: 0;
}

.policy-item ul,
.terms-item ul {
    margin: var(--spacing-sm) 0;
    padding-left: var(--spacing-md);
}

.policy-item li,
.terms-item li {
    color: var(--color-gray-600);
    line-height: 1.7;
    margin-bottom: var(--spacing-xs);
}

.contact-info {
    background-color: var(--color-gray-100);
    padding: var(--spacing-md);
    border-radius: 8px;
    margin-top: var(--spacing-sm);
}

.contact-info p {
    margin-bottom: var(--spacing-xs);
    font-size: 0.9rem;
}

.contact-info p:last-child {
    margin-bottom: 0;
}

.policy-footer,
.terms-footer {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-gray-200);
    margin-top: var(--spacing-lg);
}

.policy-footer p,
.terms-footer p {
    font-size: 0.875rem;
    color: var(--color-gray-500);
    font-style: italic;
}

/* Responsive adjustments for policy pages */
@media (max-width: 768px) {
    .policy-card,
    .terms-card {
        padding: var(--spacing-lg);
        margin: var(--spacing-sm);
    }
    
    .policy-item,
    .terms-item {
        margin-bottom: var(--spacing-lg);
        padding-bottom: var(--spacing-md);
    }
    
    .policy-item h3,
    .terms-item h3 {
        font-size: 1.125rem;
    }
}

@media (max-width: 480px) {
    .policy-card,
    .terms-card {
        padding: var(--spacing-md);
    }
    
    .contact-info {
        padding: var(--spacing-sm);
    }
}