/* ========================================
   CALIBER RESEARCH LAB - STYLESHEET
   Brand Colors: Dark Blue #1B4F72, Cyan #5DADE2
   ======================================== */

/* CSS Variables */
:root {
    --primary-dark: #1B4F72;
    --primary-cyan: #5DADE2;
    --accent-light: #85C1E9;
    --text-dark: #2C3E50;
    --text-gray: #707B7C;
    --text-light: #95A5A6;
    --bg-light: #F8F9FA;
    --bg-white: #FFFFFF;
    --border-color: #E8E8E8;
    --shadow-sm: 0 2px 8px rgba(27, 79, 114, 0.08);
    --shadow-md: 0 4px 16px rgba(27, 79, 114, 0.12);
    --shadow-lg: 0 8px 32px rgba(27, 79, 114, 0.16);
    --focus-ring: 0 0 0 3px rgba(93,173,226,0.4);
    --hero-text-color: #FFFFFF;
    --hero-text-shadow: none;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --border-radius-sm: 6px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --border-radius-xl: 16px;
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
    --touch-target-min: 44px;
}

/* Dark Theme Overrides */
[data-theme='dark'] {
    --text-dark: #E6E9EC;
    --text-gray: #B0B8C1;
    --text-light: #8A939C;
    --bg-white: #121417;
    --bg-light: #1A1F24;
    --border-color: #2A323A;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.6);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.55);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.5);
    --hero-text-color: #FFFFFF;
    --hero-text-shadow: 0 2px 6px rgba(0,0,0,0.55);
}

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

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

/* Skip to content link for accessibility */
.skip-to-content {
    position: absolute;
    top: -100px;
    left: 0;
    background: var(--primary-dark);
    color: var(--bg-white);
    padding: 1rem 2rem;
    z-index: 10000;
    text-decoration: none;
    font-weight: 600;
}

.skip-to-content:focus {
    top: 0;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text-dark);
    line-height: 1.7;
    background: var(--bg-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

[data-theme='dark'] body {
    color: var(--text-dark);
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--primary-dark);
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

h1 { 
    font-size: clamp(2rem, 5vw, 3.5rem);
    line-height: 1.2;
    margin-bottom: var(--spacing-lg);
}

h2 { 
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
}

h3 { 
    font-size: clamp(1.375rem, 3vw, 1.75rem);
    line-height: 1.4;
    margin-bottom: var(--spacing-sm);
}

h4 { 
    font-size: clamp(1.125rem, 2.5vw, 1.25rem);
    line-height: 1.5;
    margin-bottom: var(--spacing-sm);
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--text-gray);
    line-height: 1.7;
    font-size: 1rem;
}

/* Improved link styles */
a:focus-visible {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
    border-radius: var(--border-radius-sm);
}

/* Navigation with Logo */
.navbar {
    background: var(--bg-white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 4px 20px rgba(27, 79, 114, 0.15);
    backdrop-filter: blur(10px);
    padding: 0.75rem 0;
}

[data-theme='dark'] .navbar {
    background: var(--bg-light);
    box-shadow: var(--shadow-sm);
}

[data-theme='dark'] .navbar.scrolled {
    background: rgba(26,31,36,0.9);
    box-shadow: 0 4px 20px rgba(0,0,0,0.5);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

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

.navbar-logo img {
    height: 70px;
    width: auto;
    max-width: 250px;
    object-fit: contain;
    transition: all 0.3s ease;
}

.navbar.scrolled .navbar-logo img {
    height: 55px;
}

.nav-menu {
    display: flex;
    gap: 2.5rem;
    align-items: center;
    margin-left: auto;
}

.nav-menu a {
    color: var(--text-dark);
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-cyan);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    z-index: 10;
    padding: 0.5rem;
    min-width: var(--touch-target-min);
    min-height: var(--touch-target-min);
    justify-content: center;
    align-items: center;
}

.mobile-menu-toggle:focus-visible {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
    border-radius: var(--border-radius-sm);
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--primary-dark);
    transition: all var(--transition-base);
}

[data-theme='dark'] .mobile-menu-toggle span {
    background: var(--primary-cyan);
}

/* Theme Toggle Button */
.theme-toggle {
    margin-left: 1rem;
    background: var(--bg-light);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: var(--touch-target-min);
    height: var(--touch-target-min);
    min-width: var(--touch-target-min);
    min-height: var(--touch-target-min);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.1rem;
    color: var(--primary-dark);
    transition: background var(--transition-base), transform var(--transition-fast), border-color var(--transition-base);
}

.theme-toggle:hover {
    background: var(--bg-white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.theme-toggle:active {
    transform: translateY(0);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
}

[data-theme='dark'] .theme-toggle {
    background: var(--bg-white);
    color: var(--primary-cyan);
    border-color: var(--border-color);
}

[data-theme='dark'] .theme-toggle:hover {
    background: var(--bg-light);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #2874A6 100%);
    color: var(--bg-white);
    padding: 120px 0 100px;
    position: relative;
    overflow: hidden;
}

[data-theme='dark'] .hero {
    background: linear-gradient(135deg, #0F1215 0%, #1B4F72 100%);
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(93, 173, 226, 0.15) 0%, transparent 70%);
    border-radius: 50%;
}

.hero-content {
    max-width: 900px;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--hero-text-color);
    text-shadow: var(--hero-text-shadow);
}

.gradient-text {
    background: linear-gradient(90deg, var(--primary-cyan) 0%, var(--accent-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

[data-theme='dark'] .gradient-text {
    text-shadow: 0 1px 4px rgba(0,0,0,0.45);
}

.hero-subtitle {
    font-size: 1.25rem;
    line-height: 1.8;
    margin-bottom: 2.5rem;
    color: rgba(255, 255, 255, 0.9);
}

.hero-cta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    min-height: var(--touch-target-min);
    border-radius: var(--border-radius-md);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-base);
    border: 2px solid transparent;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.btn:focus-visible {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
}

.btn-primary {
    background: var(--primary-cyan);
    color: #FFFFFF !important;
}

.btn-primary:hover {
    background: var(--accent-light);
    color: #FFFFFF !important;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-primary:active {
    color: #FFFFFF !important;
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

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

.btn-secondary:hover {
    background: var(--bg-white);
    color: var(--primary-dark);
}

.btn-secondary:active {
    background: rgba(255, 255, 255, 0.9);
}

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

[data-theme='dark'] .btn-white {
    background: #FFFFFF;
    color: var(--primary-dark);
}

.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    background: rgba(255, 255, 255, 0.95);
}

[data-theme='dark'] .btn-white:hover {
    background: #FFFFFF;
}

.btn-white:active {
    transform: translateY(0);
}

/* Sections */
.section {
    padding: var(--spacing-2xl) 0;
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-xl);
}

.section-header h2 {
    margin-bottom: var(--spacing-md);
}

.section-header p {
    font-size: 1.125rem;
    line-height: 1.7;
}

/* Research Focus */
.research-focus {
    background: var(--bg-light);
}

.divisions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
    gap: 2rem;
}

.division-card {
    background: var(--bg-white);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    border: 1px solid transparent;
}

[data-theme='dark'] .division-card {
    background: var(--bg-light);
    border-color: var(--border-color);
}

.division-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-cyan);
}

.division-card:focus-within {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
}

.division-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary-cyan) 0%, var(--accent-light) 100%);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    color: var(--bg-white);
}

.division-card h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.division-card > p {
    margin-bottom: 1.5rem;
}

.division-features {
    margin-bottom: 1.5rem;
}

.division-features li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-gray);
}

.division-features li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-cyan);
    font-weight: 700;
}

.link-arrow {
    color: var(--primary-cyan);
    font-weight: 600;
    transition: all var(--transition-base);
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
}

.link-arrow:hover {
    color: var(--primary-dark);
    gap: 0.5rem;
}

[data-theme='dark'] .link-arrow:hover {
    color: var(--primary-cyan);
    opacity: 0.9;
}

.link-arrow:focus-visible {
    outline: 2px solid var(--primary-cyan);
    outline-offset: 2px;
    border-radius: var(--border-radius-sm);
}

/* Core Strengths */
.strengths-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.strength-item {
    position: relative;
}

.strength-number {
    font-size: 4rem;
    font-weight: 700;
    color: rgba(93, 173, 226, 0.1);
    margin-bottom: -2rem;
}

.strength-item h3 {
    margin-bottom: 1rem;
    position: relative;
    z-index: 1;
}

/* Research Impact */
.research-impact {
    background: var(--bg-light);
}

.impact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.impact-text h2 {
    margin-bottom: 1.5rem;
}

.impact-text p {
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
}

.impact-stats {
    display: grid;
    gap: 1.5rem;
}

.stat-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: all var(--transition-base);
}

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

[data-theme='dark'] .stat-card {
    background: var(--bg-light);
}

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-cyan);
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-gray);
    font-weight: 500;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #2874A6 100%);
    color: var(--bg-white);
}

[data-theme='dark'] .cta-section {
    background: linear-gradient(135deg, #0F1215 0%, #1B4F72 100%);
}

.cta-card {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-card h2 {
    color: var(--bg-white);
    margin-bottom: 1rem;
}

.cta-card p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
    color: rgba(255, 255, 255, 0.9);
}

/* Footer */
.footer {
    background: var(--primary-dark);
    color: var(--bg-white);
    padding: 60px 0 30px;
}

[data-theme='dark'] .footer {
    background: #0F1215;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-logo {
    height: 60px;
    width: auto;
    max-width: 250px;
    margin-bottom: 1rem;
    padding: 0.75rem;
    background: #FFFFFF;
    border-radius: 8px;
    object-fit: contain;
}

[data-theme='dark'] .footer-logo {
    background: #FFFFFF;
}

.footer-section h4 {
    color: var(--bg-white);
    margin-bottom: 1rem;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
}

[data-theme='dark'] .footer-section a {
    color: rgba(255, 255, 255, 0.9);
}

.footer-section a:hover {
    color: var(--primary-cyan);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
}

[data-theme='dark'] .footer-section p {
    color: rgba(255, 255, 255, 0.85);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: var(--spacing-xl);
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.6);
}

/* Responsive Design */
@media (max-width: 968px) {
    .hero-title { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
    
    .divisions-grid {
        grid-template-columns: 1fr;
    }
    
    .impact-content {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .navbar-logo img {
        height: 50px;
        max-width: 180px;
    }
    
    .navbar {
        padding: 0.75rem 0;
    }
    
    .navbar.scrolled {
        padding: 0.5rem 0;
    }
    
    .navbar.scrolled .navbar-logo img {
        height: 45px;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--bg-white);
        width: 100%;
        text-align: center;
        transition: var(--transition-base);
        box-shadow: var(--shadow-md);
        padding: var(--spacing-lg) 0;
        max-height: calc(100vh - 70px);
        overflow-y: auto;
        margin-left: 0;
        gap: 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-menu li {
        width: 100%;
    }
    
    .nav-menu a {
        display: block;
        padding: var(--spacing-md);
        min-height: var(--touch-target-min);
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-title { 
        font-size: clamp(1.75rem, 6vw, 2.5rem);
        line-height: 1.2;
    }
    
    .hero-subtitle { 
        font-size: clamp(1rem, 4vw, 1.125rem);
        line-height: 1.6;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-cta .btn {
        width: 100%;
    }
    
    .strengths-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }
    
    .footer-logo {
        max-width: 200px;
    }
    
    .section {
        padding: var(--spacing-xl) 0;
    }
    
    .divisions-grid {
        grid-template-columns: 1fr;
    }
}

/* Utility Classes for Pages with Inline Styles */
.page-hero {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #2874A6 100%);
    color: var(--bg-white);
    padding: var(--spacing-2xl) 0 var(--spacing-xl);
    text-align: center;
}

[data-theme='dark'] .page-hero {
    background: linear-gradient(135deg, #0F1215 0%, #1B4F72 100%);
}

.page-hero h1 {
    color: var(--bg-white);
    margin-bottom: var(--spacing-md);
}

.page-hero p {
    font-size: clamp(1.125rem, 3vw, 1.25rem);
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.7;
}

/* Content Cards */
.content-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

[data-theme='dark'] .content-card {
    background: var(--bg-light);
    border: 1px solid var(--border-color);
}

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

.content-card h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--primary-cyan);
}

.content-card p {
    color: var(--text-gray);
    line-height: 1.7;
}

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

.grid-2-col {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.grid-3-col {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

/* Centered Content */
.content-centered {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.content-narrow {
    max-width: 800px;
    margin: 0 auto;
}

.content-wide {
    max-width: 1000px;
    margin: 0 auto;
}

/* Icon Circles */
.icon-circle {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-cyan), var(--accent-light));
    border-radius: 50%;
    margin: 0 auto var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
}

/* Section Backgrounds */
.section-bg-light {
    background: var(--bg-light);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-xl);
}

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

.text-large {
    font-size: 1.125rem;
    line-height: 1.8;
}

/* Spacing Utilities */
.mb-lg {
    margin-bottom: var(--spacing-lg);
}

.mb-xl {
    margin-bottom: var(--spacing-xl);
}

.mt-lg {
    margin-top: var(--spacing-lg);
}

.mt-xl {
    margin-top: var(--spacing-xl);
}

/* Contact Page Specific */
.contact-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: all var(--transition-base);
}

[data-theme='dark'] .contact-card {
    background: var(--bg-light);
    border: 1px solid var(--border-color);
}

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

.contact-card h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--primary-dark);
}

.contact-card p {
    color: var(--text-gray);
    line-height: 1.8;
    margin-bottom: var(--spacing-sm);
}

.contact-card a {
    color: var(--primary-cyan);
    font-weight: 600;
    word-break: break-all;
    transition: color var(--transition-base);
}

.contact-card a:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

[data-theme='dark'] .contact-card a:hover {
    color: var(--primary-cyan);
    opacity: 0.9;
}

/* Capabilities Page Specific */
.capability-card {
    padding: var(--spacing-lg);
    background: var(--bg-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

[data-theme='dark'] .capability-card {
    background: var(--bg-light);
    border: 1px solid var(--border-color);
}

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

.capability-card h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--primary-cyan);
}

.capability-card p {
    color: var(--text-gray);
}