/* ============================================
   Cambridge Industrialisation Website Styles
   ============================================ */

/* CSS Variables */
:root {
    /* Cambridge Blue Palette */
    --cambridge-blue: #003E74;
    --cambridge-blue-dark: #002952;
    --cambridge-blue-light: #0055A3;
    --cambridge-gold: #C4A75B;
    --cambridge-gold-light: #D4B76C;
    
    /* Neutral Colors */
    --white: #FFFFFF;
    --off-white: #F8F9FA;
    --light-gray: #E9ECEF;
    --gray: #6C757D;
    --dark-gray: #343A40;
    --black: #1A1A1A;
    
    /* Accent Colors */
    --accent-red: #C13832;
    --accent-teal: #0097A7;
    
    /* Typography */
    --font-serif: 'Crimson Pro', Georgia, serif;
    --font-sans: 'Source Sans 3', -apple-system, BlinkMacSystemFont, sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2.5rem;
    --spacing-xl: 4rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.15);
}

/* ============================================
   Reset & Base Styles
   ============================================ */

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

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

body {
    font-family: var(--font-sans);
    font-weight: 400;
    line-height: 1.6;
    color: var(--dark-gray);
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    font-weight: 700;
    line-height: 1.2;
    color: var(--cambridge-blue-dark);
    margin-bottom: var(--spacing-md);
}

h1 { font-size: 3.5rem; }
h2 { font-size: 2.5rem; }
h3 { font-size: 1.875rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1.125rem; }

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

.lead {
    font-size: 1.25rem;
    font-weight: 400;
    line-height: 1.7;
    color: var(--dark-gray);
}

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

a:hover {
    color: var(--cambridge-blue-light);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

@media (min-width: 768px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
}

/* Utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }

/* ============================================
   Navigation
   ============================================ */

.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--white);
    border-bottom: 1px solid var(--light-gray);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

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

.logo-link {
    display: flex;
    align-items: center;
}

.logo {
    height: 50px;
    width: auto;
    transition: transform var(--transition-fast);
}

.logo:hover {
    transform: scale(1.05);
}

.nav-menu {
    display: none;
    list-style: none;
    gap: var(--spacing-lg);
    align-items: center;
}

@media (min-width: 768px) {
    .nav-menu {
        display: flex;
    }
}

.nav-menu a {
    font-size: 1rem;
    font-weight: 600;
    color: var(--dark-gray);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 4px;
    transition: all var(--transition-fast);
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--cambridge-blue);
    transition: all var(--transition-fast);
    transform: translateX(-50%);
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--cambridge-blue);
}

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

/* Dropdown */
.dropdown {
    position: relative;
}

.dropdown-toggle::after {
    content: ' ▾';
    font-size: 0.875rem;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 220px;
    background: var(--white);
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    list-style: none;
    padding: var(--spacing-sm);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-normal);
}

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

.dropdown-menu li {
    margin: 0;
}

.dropdown-menu a {
    display: block;
    padding: var(--spacing-sm);
    border-radius: 4px;
    color: var(--dark-gray);
}

.dropdown-menu a::after {
    display: none;
}

.dropdown-menu a:hover {
    background: var(--off-white);
    color: var(--cambridge-blue);
}

/* Language Switch */
.lang-btn {
    padding: var(--spacing-xs) var(--spacing-sm);
    background: transparent;
    border: 1px solid var(--gray);
    border-radius: 4px;
    color: var(--gray);
    font-size: 0.875rem;
    cursor: not-allowed;
    opacity: 0.6;
}

.lang-btn:not(:disabled) {
    cursor: pointer;
    opacity: 1;
}

.lang-btn:not(:disabled):hover {
    background: var(--cambridge-blue);
    color: var(--white);
    border-color: var(--cambridge-blue);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

@media (min-width: 768px) {
    .mobile-menu-toggle {
        display: none;
    }
}

.mobile-menu-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--cambridge-blue);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
    position: relative;
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--cambridge-blue-dark) 0%, var(--cambridge-blue) 50%, var(--cambridge-blue-light) 100%);
    overflow: hidden;
}

.hero-background {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(circle at 20% 80%, rgba(196, 167, 91, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.05) 0%, transparent 50%);
    animation: heroBackgroundShift 20s ease-in-out infinite;
}

@keyframes heroBackgroundShift {
    0%, 100% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.1) rotate(2deg); }
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    color: var(--white);
    padding: var(--spacing-xl) var(--spacing-md);
    animation: heroFadeIn 1s ease-out;
}

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

.hero-badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    margin-bottom: var(--spacing-md);
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: heroFadeIn 1s ease-out 0.2s both;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 700;
    color: var(--white);
    margin-bottom: var(--spacing-sm);
    animation: heroFadeIn 1s ease-out 0.4s both;
}

.hero-subtitle {
    font-size: clamp(1.25rem, 3vw, 2rem);
    font-weight: 300;
    color: var(--cambridge-gold-light);
    margin-bottom: var(--spacing-xs);
    animation: heroFadeIn 1s ease-out 0.6s both;
}

.hero-tagline {
    font-size: clamp(1rem, 2vw, 1.25rem);
    font-weight: 400;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--spacing-xl);
    animation: heroFadeIn 1s ease-out 0.8s both;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    animation: heroFadeIn 1s ease-out 1s both;
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-family: var(--font-sans);
    font-size: 1rem;
    font-weight: 600;
    text-align: center;
    border-radius: 6px;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: 2px solid transparent;
    text-decoration: none;
}

.btn-primary {
    background: var(--white);
    color: var(--cambridge-blue);
    border-color: var(--white);
}

.btn-primary:hover {
    background: var(--cambridge-gold);
    color: var(--white);
    border-color: var(--cambridge-gold);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: transparent;
    color: var(--white);
    border-color: var(--white);
}

.btn-secondary:hover {
    background: var(--white);
    color: var(--cambridge-blue);
}

.btn-accent {
    background: var(--cambridge-gold);
    color: var(--white);
    border-color: var(--cambridge-gold);
}

.btn-accent:hover {
    background: var(--cambridge-gold-light);
    border-color: var(--cambridge-gold-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-outline {
    background: transparent;
    color: var(--cambridge-blue);
    border-color: var(--cambridge-blue);
}

.btn-outline:hover {
    background: var(--cambridge-blue);
    color: var(--white);
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.125rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
}

.btn-text {
    font-weight: 700;
}

.btn-subtext {
    font-size: 0.875rem;
    font-weight: 400;
    opacity: 0.9;
}

.btn-sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: 0.875rem;
}

/* ============================================
   Announcement Banner
   ============================================ */

.announcement-banner {
    background: linear-gradient(90deg, var(--cambridge-gold) 0%, var(--cambridge-gold-light) 100%);
    padding: var(--spacing-md) 0;
    box-shadow: var(--shadow-md);
}

.announcement-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    justify-content: center;
}

.announcement-icon {
    font-size: 1.5rem;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.announcement-text {
    flex: 1;
    min-width: 300px;
    color: var(--white);
}

.announcement-text strong {
    display: block;
    font-size: 1.125rem;
    margin-bottom: 0.25rem;
}

.announcement-theme {
    font-size: 0.875rem;
    opacity: 0.95;
}

.announcement-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* ============================================
   Sections
   ============================================ */

.section {
    padding: var(--spacing-xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.section-title {
    font-size: clamp(2rem, 4vw, 2.5rem);
    color: var(--cambridge-blue-dark);
    margin-bottom: var(--spacing-sm);
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--gray);
    font-weight: 300;
}

/* About Section */
.section-about {
    background: var(--off-white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
    align-items: start;
}

@media (min-width: 968px) {
    .about-grid {
        grid-template-columns: 1.5fr 1fr;
    }
}

.about-text {
    font-size: 1.0625rem;
    line-height: 1.8;
}

.mission-statement {
    background: var(--white);
    padding: var(--spacing-lg);
    border-left: 4px solid var(--cambridge-gold);
    border-radius: 8px;
    margin: var(--spacing-lg) 0;
    box-shadow: var(--shadow-sm);
}

.mission-statement h3 {
    font-size: 1.5rem;
    color: var(--cambridge-blue);
    margin-bottom: var(--spacing-sm);
}

.link-arrow {
    display: inline-flex;
    align-items: center;
    font-weight: 600;
    color: var(--cambridge-blue);
    margin-top: var(--spacing-md);
    transition: all var(--transition-fast);
}

.link-arrow:hover {
    color: var(--cambridge-blue-light);
    transform: translateX(5px);
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.stat-card {
    background: var(--white);
    padding: var(--spacing-md);
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.stat-number {
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 700;
    color: var(--cambridge-blue);
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--gray);
    line-height: 1.3;
}

/* Framework Preview */
.framework-preview {
    background: var(--white);
    padding: var(--spacing-lg);
    border-radius: 12px;
    box-shadow: var(--shadow-md);
}

.framework-preview h4 {
    font-size: 1.25rem;
    color: var(--cambridge-blue);
    margin-bottom: var(--spacing-md);
    text-align: center;
}

.framework-stages {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
}

.stage {
    flex: 1;
    text-align: center;
    padding: var(--spacing-md);
    background: var(--off-white);
    border-radius: 8px;
    transition: all var(--transition-normal);
}

.stage:hover {
    background: var(--cambridge-blue);
    color: var(--white);
    transform: scale(1.05);
}

.stage-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-xs);
}

.stage-name {
    font-weight: 700;
    font-size: 1.125rem;
}

.stage-arrow {
    font-size: 1.5rem;
    color: var(--cambridge-gold);
    font-weight: 700;
}

/* Conference Section */
.section-conference {
    background: var(--cambridge-blue-dark);
    color: var(--white);
}

.conference-highlight {
    max-width: 900px;
    margin: 0 auto;
}

.conference-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid rgba(255, 255, 255, 0.2);
}

.conference-year {
    font-family: var(--font-serif);
    font-size: 4rem;
    font-weight: 700;
    color: var(--cambridge-gold);
    line-height: 1;
    margin-bottom: var(--spacing-sm);
}

.conference-header h2 {
    color: var(--white);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.conference-theme {
    font-size: 1.5rem;
    color: var(--cambridge-gold-light);
    font-weight: 300;
}

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

.conference-info {
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

.info-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.info-label {
    font-size: 0.875rem;
    color: var(--cambridge-gold-light);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.25rem;
}

.info-value {
    font-size: 1.125rem;
    font-weight: 600;
    line-height: 1.4;
}

.conference-tracks {
    background: rgba(255, 255, 255, 0.05);
    padding: var(--spacing-lg);
    border-radius: 12px;
    margin-bottom: var(--spacing-lg);
}

.conference-tracks h3 {
    color: var(--cambridge-gold);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
}

.tracks-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-sm);
}

.tracks-list li {
    padding: var(--spacing-sm);
    background: rgba(255, 255, 255, 0.05);
    border-left: 3px solid var(--cambridge-gold);
    border-radius: 4px;
    transition: all var(--transition-fast);
}

.tracks-list li:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateX(5px);
}

.conference-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* Quick Links Section */
.section-quick-links {
    background: var(--off-white);
}

.quick-links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.quick-link-card {
    position: relative;
    background: var(--white);
    padding: var(--spacing-lg);
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    border: 2px solid transparent;
    display: block;
    text-decoration: none;
}

.quick-link-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--cambridge-gold);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.quick-link-card h3 {
    font-size: 1.5rem;
    color: var(--cambridge-blue);
    margin-bottom: var(--spacing-sm);
}

.quick-link-card p {
    color: var(--gray);
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.card-arrow {
    position: absolute;
    bottom: var(--spacing-md);
    right: var(--spacing-md);
    font-size: 1.5rem;
    color: var(--cambridge-gold);
    transition: all var(--transition-fast);
}

.quick-link-card:hover .card-arrow {
    transform: translateX(5px);
}

/* ============================================
   Footer
   ============================================ */

.footer {
    background: var(--cambridge-blue-dark);
    color: var(--white);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-logo {
    height: 60px;
    width: auto;
    margin-bottom: var(--spacing-md);
}

.footer-tagline {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--cambridge-gold-light);
    margin-bottom: var(--spacing-xs);
}

.footer-affiliation {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

.footer-section h4 {
    color: var(--cambridge-gold);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
}

.footer-links,
.footer-contact {
    list-style: none;
}

.footer-links li,
.footer-contact li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a,
.footer-contact a {
    color: rgba(255, 255, 255, 0.8);
    transition: color var(--transition-fast);
}

.footer-links a:hover,
.footer-contact a:hover {
    color: var(--cambridge-gold-light);
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
}

.footer-credit {
    margin-top: var(--spacing-xs);
}

/* ============================================
   Responsive Adjustments
   ============================================ */

@media (max-width: 768px) {
    h1 { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
    h3 { font-size: 1.5rem; }
    
    .hero {
        min-height: 70vh;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
    }
    
    .announcement-content {
        flex-direction: column;
        text-align: center;
    }
    
    .conference-cta {
        flex-direction: column;
    }
    
    .btn-large {
        width: 100%;
    }
}

/* ============================================
   Animations
   ============================================ */

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

.fade-in-up {
    animation: fadeInUp 0.8s ease-out;
}

/* Scroll reveal */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}