/* ============================================
   VisualHub - Base Styles
   Dark Navy + Neon Blue/Purple Theme
   ============================================ */

/* CSS Variables */
:root {
    /* Colors - Dark Navy Base */
    --color-bg-primary: #0a0e27;
    --color-bg-secondary: #131829;
    --color-bg-tertiary: #1a1f3a;
    
    /* Neon Accents */
    --color-accent-primary: #37B6FF;
    --color-accent-secondary: #8A5CFF;
    --color-accent-glow: rgba(55, 182, 255, 0.4);
    
    /* Luxury Gold (for theme 02) */
    --color-gold-primary: #C9A86A;
    --color-gold-secondary: #F2D6A2;
    
    /* Text Colors */
    --color-text-primary: #FFFFFF;
    --color-text-secondary: #B8C1EC;
    --color-text-muted: #6B7A99;
    
    /* UI Elements */
    --color-border: rgba(184, 193, 236, 0.1);
    --color-border-light: rgba(184, 193, 236, 0.05);
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, var(--color-accent-primary), var(--color-accent-secondary));
    --gradient-glow: radial-gradient(circle at 50% 50%, var(--color-accent-glow), transparent);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 1rem;
    --radius-lg: 1.5rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 20px var(--color-accent-glow);
    
    /* Typography */
    --font-primary: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.5rem;
    --font-size-2xl: 2rem;
    --font-size-3xl: 3rem;
    --font-size-4xl: 4rem;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    background-color: var(--color-bg-primary);
    color: var(--color-text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container-sm {
    max-width: 1200px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-sm);
}

h1 {
    font-size: var(--font-size-4xl);
    font-weight: 800;
}

h2 {
    font-size: var(--font-size-3xl);
}

h3 {
    font-size: var(--font-size-2xl);
}

h4 {
    font-size: var(--font-size-xl);
}

p {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-secondary);
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition-fast);
}

/* Loading Screen */
#loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--color-bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

#loading-screen.hidden {
    opacity: 0;
    visibility: hidden;
}

.loader {
    width: 50px;
    height: 50px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Navigation */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(10, 14, 39, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: var(--transition-normal);
}

.main-nav.scrolled {
    background: rgba(10, 14, 39, 0.95);
    box-shadow: var(--shadow-md);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-sm) 0;
}

.logo {
    display: flex;
    align-items: center;
    font-size: var(--font-size-xl);
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo-img {
    height: 40px;
    width: auto;
}

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

.nav-link {
    color: var(--color-text-secondary);
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-accent-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transform: translateX(-50%);
    transition: var(--transition-fast);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 80%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

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

/* Footer */
.main-footer {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    margin-top: var(--spacing-xl);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 3fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-brand .footer-logo {
    height: 40px;
    margin-bottom: var(--spacing-sm);
}

.footer-tagline {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-md);
}

/* Footer Contact List */
.footer-contact-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: var(--spacing-md);
}

.footer-contact-item {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    transition: var(--transition-fast);
}

.footer-contact-item:hover {
    color: var(--color-accent-primary);
}

.footer-contact-item i {
    color: var(--color-accent-primary);
    font-size: 0.875rem;
    width: 18px;
    text-align: center;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
}

.footer-column h4 {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
    font-size: var(--font-size-base);
}

.footer-column ul {
    list-style: none;
}

.footer-column li {
    margin-bottom: var(--spacing-xs);
}

.footer-column a {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    transition: var(--transition-fast);
}

.footer-column a:hover {
    color: var(--color-accent-primary);
}

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

.social-links a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: var(--transition-fast);
}

.social-links a:hover {
    border-color: var(--color-accent-primary);
    background: rgba(55, 182, 255, 0.1);
    color: var(--color-accent-primary);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border-light);
}

.footer-bottom p {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    margin: 0;
}

.admin-link {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    opacity: 0.5;
    transition: var(--transition-fast);
}

.admin-link:hover {
    opacity: 1;
    color: var(--color-accent-primary);
}

/* Responsive Design */
@media (max-width: 1024px) {
    h1 { font-size: var(--font-size-3xl); }
    h2 { font-size: var(--font-size-2xl); }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
    }
    
    h1 { font-size: var(--font-size-2xl); }
    h2 { font-size: var(--font-size-xl); }
    
    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        flex-direction: column;
        background: rgba(10, 14, 39, 0.98);
        backdrop-filter: blur(10px);
        padding: var(--spacing-md);
        gap: var(--spacing-sm);
        transform: translateX(-100%);
        transition: var(--transition-normal);
        border-bottom: 1px solid var(--color-border);
    }
    
    .nav-links.active {
        transform: translateX(0);
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
    
    .footer-links {
        grid-template-columns: 1fr;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-xs);
        text-align: center;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
}