/* CSS Variables - Design System */
:root {
    --primary: hsl(217, 91%, 60%);
    --primary-hover: hsl(217, 91%, 55%);
    --primary-foreground: hsl(0, 0%, 100%);
    --secondary: hsl(220, 14%, 20%);
    --secondary-hover: hsl(220, 14%, 25%);
    --background: hsl(0, 0%, 98%);
    --foreground: hsl(220, 15%, 15%);
    --muted: hsl(220, 14%, 96%);
    --muted-foreground: hsl(220, 9%, 46%);
    --card: hsl(0, 0%, 100%);
    --nav-bg: hsl(220, 15%, 8%);
    --footer-bg: hsl(220, 14%, 20%);
    
    /* Shadows */
    --shadow-sm: 0 2px 8px hsla(220, 15%, 15%, 0.05);
    --shadow-md: 0 4px 16px hsla(220, 15%, 15%, 0.1);
    --shadow-lg: 0 8px 32px hsla(220, 15%, 15%, 0.15);
    --shadow-glow: 0 0 30px hsla(217, 91%, 60%, 0.3);
    --shadow-glow-lg: 0 0 50px hsla(217, 91%, 60%, 0.4);
    --shadow-hover: 0 12px 40px hsla(220, 15%, 15%, 0.2);
    
    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: all 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

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

html {
    scroll-behavior: smooth;
    height: -webkit-fill-available;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--foreground);
    background-color: var(--background);
    overflow-x: hidden;
    min-height: 100vh;
    min-height: -webkit-fill-available;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header Styles */
header {
    background: var(--nav-bg);
    color: var(--primary-foreground);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: var(--transition);
}

header.scrolled {
    background: var(--nav-bg);
    box-shadow: var(--shadow-lg);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-foreground);
    z-index: 1002;
}

/* Navigation */
.nav-container {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    color: var(--primary-foreground);
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
    background: rgba(255, 255, 255, 0.1);
}

/* Language Switcher */
.language-switcher {
    position: relative;
    z-index: 1002;
}

.lang-btn {
    background: transparent;
    border: 2px solid var(--primary-foreground);
    color: var(--primary-foreground);
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
    font-weight: 500;
}

.lang-btn:hover {
    background: var(--primary-foreground);
    color: var(--nav-bg);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--card);
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
    min-width: 120px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: var(--transition);
    z-index: 1001;
}

.lang-dropdown.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-option {
    padding: 0.75rem 1rem;
    cursor: pointer;
    transition: var(--transition);
    color: var(--foreground);
    border-bottom: 1px solid var(--muted);
}

.lang-option:last-child {
    border-bottom: none;
}

.lang-option:hover {
    background: var(--primary);
    color: var(--primary-foreground);
}

/* Hamburger Menu */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 0.5rem;
    background: none;
    border: none;
    z-index: 1002;
}

.hamburger span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--primary-foreground);
    margin: 3px 0;
    transition: var(--transition);
    border-radius: 2px;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* Section Styles */
section {
    padding: 5rem 2rem;
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

section.visible {
    opacity: 1;
    transform: translateY(0);
}

.section-title {
    text-align: center;
    margin-bottom: 4rem;
    overflow: hidden;
}

.section-title h2 {
    font-size: 3rem;
    font-weight: 700;
    color: var(--foreground);
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-title h2::after {
    content: '';
    position: absolute;
    width: 0;
    height: 4px;
    background: var(--primary);
    bottom: -10px;
    left: 0;
    transition: width 1s ease;
}

.section-title.visible h2::after {
    width: 100%;
}

.section-title p {
    font-size: 1.2rem;
    color: var(--muted-foreground);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 0.5rem;
    transition: var(--transition-bounce);
    cursor: pointer;
    border: none;
    text-decoration: none;
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: left 0.5s;
    z-index: -1;
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: var(--primary);
    color: var(--primary-foreground);
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-5px);
    box-shadow: var(--shadow-glow-lg);
}

.btn-outline {
    background: transparent;
    color: var(--primary-foreground);
    border: 2px solid var(--primary-foreground);
    backdrop-filter: blur(10px);
}

.btn-outline:hover {
    background: var(--primary-foreground);
    color: var(--secondary);
    transform: translateY(-5px);
}

/* Animations */
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-15px); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

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

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-50px); }
    to { opacity: 1; transform: translateX(0); }
}

.animate-float { animation: float 6s ease-in-out infinite; }
.animate-fade-in-up { animation: fadeInUp 0.8s ease-out forwards; }
.animate-slide-in-right { animation: slideInRight 0.8s ease-out forwards; }
.animate-slide-in-left { animation: slideInLeft 0.8s ease-out forwards; }

/* Mobile Responsive Design */
@media (max-width: 992px) {
    .container {
        padding: 0 1.5rem;
    }

    .section-title h2 { 
        font-size: 2.5rem; 
    }
    
    section { 
        padding: 4rem 1rem; 
    }

    /* Mobile Navigation */
    .hamburger {
        display: flex;
    }
    
    .nav-container {
        gap: 1rem;
    }
    
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        height: 100dvh;
        background: var(--nav-bg);
        flex-direction: column;
        align-items: center;
        justify-content: flex-start;
        padding-top: 5rem;
        transition: var(--transition);
        box-shadow: var(--shadow-lg);
        z-index: 1000;
        gap: 0;
    }
    
    .nav-links.active {
        right: 0;
        transform: translate3d(0, 0, 0);
    }
    
    .nav-links li {
        width: 100%;
        text-align: center;
    }
    
    .nav-links a {
        display: block;
        padding: 1rem 1.5rem;
        font-size: 1.1rem;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        width: 100%;
        min-height: 60px;
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    /* Language switcher in mobile menu */
    .nav-links .language-switcher {
        margin-top: 2rem;
        width: 100%;
        padding: 0 1.5rem;
    }
    
    .nav-links .lang-btn {
        width: 100%;
        justify-content: center;
    }
    
    .nav-links .lang-dropdown {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        background: transparent;
        display: none;
    }
    
    .nav-links .lang-dropdown.active {
        display: block;
    }
    
    .nav-links .lang-option {
        color: var(--primary-foreground);
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        text-align: center;
    }
    
    /* Prevent body scroll when menu is open */
    body.menu-open {
        overflow: hidden;
    }
    
    /* Backdrop overlay */
    .nav-links::before {
        content: '';
        position: fixed;
        top: 0;
        left: 0;
        width: 100vw;
        height: 100vh;
        background: rgba(0, 0, 0, 0.5);
        z-index: -1;
        opacity: 0;
        transition: opacity 0.3s ease;
    }
    
    .nav-links.active::before {
        opacity: 1;
    }
}

@media (max-width: 768px) {
    /* Base mobile adjustments */
    body {
        font-size: 14px;
        line-height: 1.5;
    }

    .container {
        padding: 0 1rem;
    }

    /* Section spacing for mobile */
    section {
        padding: 3rem 1rem;
    }

    /* Improved section titles for mobile */
    .section-title {
        margin-bottom: 2.5rem;
    }

    .section-title h2 {
        font-size: 2rem;
        margin-bottom: 0.5rem;
    }

    .section-title p {
        font-size: 1rem;
    }

    /* Better button sizing for touch */
    .btn {
        padding: 0.875rem 1.5rem;
        font-size: 0.9rem;
        min-height: 44px;
        min-width: 44px;
    }

    /* Enhanced hamburger menu */
    .hamburger {
        padding: 0.75rem;
    }

    .hamburger span {
        width: 30px;
        height: 3px;
    }

    /* Header adjustments */
    .header-content {
        padding: 0.75rem 0;
    }

    /* Improved mobile navigation */
    .nav-links {
        width: 85%;
        max-width: 280px;
        padding-top: 4rem;
    }

    /* Hide desktop language switcher */
    .nav-container .language-switcher {
        display: none;
    }
}

@media (max-width: 576px) {
    /* Extra small devices */
    section {
        padding: 2rem 1rem;
    }

    .section-title h2 {
        font-size: 1.75rem;
    }

    .section-title p {
        font-size: 0.9rem;
    }

    .btn {
        padding: 0.75rem 1.25rem;
        font-size: 0.85rem;
    }

    /* Even more compact navigation */
    .nav-links {
        width: 90%;
        padding-top: 3.5rem;
    }

    .nav-links a {
        padding: 0.875rem 1rem;
        font-size: 1rem;
    }

    .logo {
        font-size: 1.3rem;
    }
}

/* Mobile landscape orientation */
@media (max-height: 500px) and (max-width: 992px) {
    .nav-links {
        padding-top: 2rem;
    }

    .nav-links a {
        padding: 0.75rem 1.5rem;
    }
}

/* Safe area insets for modern phones */
@supports(padding: max(0px)) {
    .container {
        padding-left: max(1rem, env(safe-area-inset-left));
        padding-right: max(1rem, env(safe-area-inset-right));
    }
    
    .nav-links {
        padding-top: max(4rem, env(safe-area-inset-top));
        padding-bottom: env(safe-area-inset-bottom);
    }
}

/* Reduced motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .animate-float,
    .animate-glow {
        animation: none;
    }
}

/* Touch device improvements */
@media (hover: none) and (pointer: coarse) {
    .btn:hover {
        transform: none;
    }

    .btn-primary:hover {
        transform: none;
        box-shadow: var(--shadow-glow);
    }

    /* Remove hover effects on touch devices */
    .nav-link:hover {
        color: inherit;
    }
}

/* Utility Classes */
.mobile-only {
    display: none !important;
}

.desktop-only {
    display: block !important;
}

.text-center-mobile {
    text-align: center;
}

@media (max-width: 768px) {
    .mobile-only {
        display: block !important;
    }
    
    .desktop-only {
        display: none !important;
    }
    
    .text-center-mobile {
        text-align: center;
    }
}