/* ============================================
   JSA Climate - Modern Responsive Design System
   ============================================ */

/* CSS Variables for Design System */
:root {
    /* Colors - Peach & Rose Palette */
    --color-primary: #6d6875;        /* Dim Grey - headers, navigation */
    --color-primary-dark: #6d6875;
    --color-accent: #b5838d;         /* Dusty Rose - accents */
    --color-accent-warm: #e5989b;    /* Cotton Candy - warm accents */
    --color-accent-light: #ffb4a2;   /* Powder Blush */
    --color-accent-lightest: #ffcdb2; /* Peach Fuzz */
    --color-bg: #f5f5f5;
    --color-bg-white: #ffffff;
    --color-text: #2c2c2c;
    --color-text-light: #666666;
    --color-border: #e0e0e0;
    --color-hover: #e5989b;
    
    /* Spacing System */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 0.8rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    
    /* Typography */
    --font-primary: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'IBM Plex Mono', 'Courier New', monospace;
    
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.5rem;
    --text-2xl: 2rem;
    --text-3xl: 2.5rem;
    
    /* Layout */
    --container-max: 1200px;
    --container-narrow: 800px;
    --border-radius: 4px;
    --border-radius-lg: 8px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
}

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

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-primary);
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

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

ul {
    list-style: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

/* ============================================
   Header & Navigation
   ============================================ */

.site-header {
    background-color: var(--color-primary);
    color: white;
    padding: var(--space-md) var(--space-lg);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.header-container {
    max-width: var(--container-max);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-md);
}

.site-branding {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.site-logo {
    width: 60px;
    height: 60px;
    flex-shrink: 0;
}

.site-title {
    font-size: var(--text-xl);
    font-weight: 600;
    letter-spacing: 0.02em;
}

/* Navigation */
.main-nav ul {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.main-nav a {
    padding: var(--space-xs) 0;
    font-weight: 500;
    font-size: var(--text-lg);
    position: relative;
}

.main-nav a:hover {
    color: var(--color-accent-light);
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: white;
    transition: width var(--transition-base);
}

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

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

.dropdown-toggle {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    cursor: pointer;
}

.dropdown-arrow {
    font-size: var(--text-xs);
    transition: transform var(--transition-fast);
}

.dropdown:hover .dropdown-arrow {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    margin-top: var(--space-sm);
    min-width: 200px;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-base);
}

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

.dropdown-menu a {
    display: block;
    padding: var(--space-sm) var(--space-md);
    color: var(--color-text);
    font-weight: 500;
    border-bottom: 1px solid var(--color-border);
}

.dropdown-menu a:last-child {
    border-bottom: none;
}

.dropdown-menu a:hover {
    background: var(--color-bg);
    color: var(--color-accent);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: var(--space-xs);
}

.menu-toggle span {
    width: 24px;
    height: 2px;
    background: white;
    transition: all var(--transition-fast);
}

/* ============================================
   Main Content Layout
   ============================================ */

.main-content {
    flex: 1;
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-xl) var(--space-lg);
}

/* Intro Grid (Homepage) */
.intro-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--space-xl);
    align-items: start;
}

.intro-left p {
    line-height: 1.7;
    color: var(--color-text);
    margin-top: var(--space-sm);
}

.intro-right {
    padding: var(--space-md);
    background: var(--color-bg);
    border-radius: var(--border-radius-lg);
    border-left: 3px solid var(--color-accent);
}

.intro-right h3 {
    font-size: var(--text-xl);
    color: var(--color-primary);
    margin-bottom: var(--space-xs);
}

.intro-right .affiliation {
    font-size: var(--text-sm);
    color: var(--color-text-light);
    margin-bottom: var(--space-md);
}

.contact-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.contact-link {
    display: flex;
    align-items: center;
    padding: var(--space-xs);
    background: white;
    border-radius: var(--border-radius);
    color: var(--color-accent);
    font-weight: 500;
    font-size: var(--text-sm);
    transition: all var(--transition-base);
    border: 1px solid var(--color-border);
}

.contact-link:hover {
    background: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
    transform: translateX(4px);
}

.content-section {
    background: var(--color-bg-white);
    border-radius: var(--border-radius-lg);
    padding: var(--space-md);
    margin-bottom: var(--space-lg);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.section-header {
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--color-border);
}

.section-title {
    font-size: var(--text-2xl);
    font-weight: 600;
    color: var(--color-primary-dark);
    margin-bottom: var(--space-xs);
}

.section-subtitle {
    font-size: var(--text-base);
    color: var(--color-text-light);
    font-weight: 400;
}

/* ============================================
   Button System
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: 0.4rem 0.75rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    font-size: var(--text-sm);
    transition: all var(--transition-base);
    text-align: center;
}

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

.btn-primary:hover {
    background: var(--color-primary);
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.btn-secondary {
    background: var(--color-bg);
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

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

/* Active state for clicked buttons */
.btn.active {
    background: var(--color-accent);
    color: white;
    border-color: var(--color-accent);
}

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

.btn-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    justify-content: center;
    margin: var(--space-sm) 0;
}

/* ============================================
   Image Gallery / Viewer System
   ============================================ */

.image-viewer {
    margin-top: var(--space-sm);
}

.image-controls {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    justify-content: center;
    margin-bottom: var(--space-md);
}

.image-viewer .image-display {
    position: relative;
    width: 100%;
    min-height: 400px;
    background: var(--color-bg);
    border-radius: var(--border-radius);
    overflow: auto;
}

.image-display {
    position: relative;
    width: fit-content;
    max-width: 900px;
    margin: 0 auto;
    background: var(--color-bg);
    border-radius: var(--border-radius);
    padding: var(--space-xs);
    overflow: auto;
    text-align: center;
    display: block;
}

.image-display img {
    width: 100%;
    max-width: 100%;
    height: auto;
    opacity: 0;
    display: none;
    transition: opacity var(--transition-base);
    margin: 0;
    vertical-align: bottom;
}

.image-display img.active {
    opacity: 1;
    display: block;
    position: relative;
}

/* Hovmöller images - increase vertical size */
.monitoring-section .image-display img {
    width: auto;
    max-height: 80vh;
    margin: 0 auto;
}

/* ============================================
   Research Publications
   ============================================ */

.publication {
    margin-bottom: var(--space-xl);
}

.publication-header {
    margin-bottom: var(--space-md);
}

.publication-title {
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-primary-dark);
    margin-bottom: var(--space-sm);
    line-height: 1.3;
}

.publication-links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.publication-content {
    display: grid;
    gap: var(--space-lg);
    align-items: start;
}

.publication-text {
    line-height: 1.7;
    color: var(--color-text);
}

.publication-text h3 {
    font-size: var(--text-lg);
    margin-bottom: var(--space-sm);
    color: var(--color-primary);
}

.publication-text p {
    margin-bottom: var(--space-md);
}

.publication-image {
    text-align: center;
}

.publication-image img {
    max-width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* ============================================
   Monitoring Controls
   ============================================ */

.monitoring-section {
    margin-bottom: var(--space-xl);
}

.monitoring-header {
    text-align: center;
    margin-bottom: var(--space-lg);
}

.monitoring-category {
    font-size: var(--text-lg);
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--space-sm);
    text-decoration: underline;
    text-decoration-thickness: 2px;
    text-underline-offset: 4px;
}

.text-description {
    margin-top: var(--space-sm);
    padding: var(--space-md);
    background: var(--color-bg);
    border-radius: var(--border-radius);
    border-left: 3px solid var(--color-accent);
}

.text-description p {
    line-height: 1.7;
    color: var(--color-text);
    margin: 0;
}

.control-group {
    margin-bottom: var(--space-xl);
}

.btn-oceanic {
    background: var(--color-accent);
    color: white;
}

.btn-oceanic:hover {
    background: var(--color-primary-dark);
}

.btn-atmospheric {
    background: var(--color-accent-warm);
    color: white;
}

.btn-atmospheric:hover {
    background: var(--color-primary-dark);
}

/* ============================================
   About / Bio Section
   ============================================ */

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

.bio-text h2 {
    font-size: var(--text-xl);
    color: var(--color-primary);
    margin-bottom: var(--space-md);
}

.bio-text p {
    line-height: 1.8;
    margin-bottom: var(--space-md);
    color: var(--color-text);
}

.bio-image {
    text-align: center;
}

.bio-image img {
    max-width: 300px;
    border-radius: var(--border-radius-lg);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}

/* ============================================
   PDF Embed
   ============================================ */

.pdf-embed {
    margin-top: var(--space-lg);
}

.pdf-embed embed {
    width: 100%;
    min-height: 800px;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius);
}

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

.site-footer {
    background: var(--color-primary-dark);
    color: white;
    padding: var(--space-lg);
    text-align: center;
    margin-top: auto;
}

.site-footer p {
    font-size: var(--text-sm);
    opacity: 0.9;
}

/* ============================================
   Responsive Design - Mobile First
   ============================================ */

/* Tablets and up */
@media (min-width: 768px) {
    .bio-section {
        grid-template-columns: 2fr 1fr;
    }
    
    .publication-content {
        grid-template-columns: 1fr 1fr;
    }
    
    .image-display {
        min-height: 500px;
    }
}

/* Mobile Styles */
@media (max-width: 767px) {
    :root {
        --text-2xl: 1.5rem;
        --text-xl: 1.25rem;
    }
    
    .intro-grid {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }
    
    .header-container {
        flex-wrap: wrap;
    }
    
    .menu-toggle {
        display: flex;
        order: 1;
    }
    
    .site-branding {
        order: 0;
    }
    
    .main-nav {
        order: 2;
        width: 100%;
        display: none;
    }
    
    .main-nav.active {
        display: block;
    }
    
    .main-nav ul {
        flex-direction: column;
        gap: 0;
        margin-top: var(--space-md);
        border-top: 1px solid rgba(255, 255, 255, 0.2);
    }
    
    .main-nav li {
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }
    
    .main-nav a {
        display: block;
        padding: var(--space-md);
    }
    
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        margin-top: 0;
        background: rgba(0, 0, 0, 0.1);
        display: none;
    }
    
    .dropdown.active .dropdown-menu {
        display: block;
    }
    
    .main-content {
        padding: var(--space-lg) var(--space-md);
    }
    
    .content-section {
        padding: var(--space-lg);
    }
    
    .btn-group {
        justify-content: stretch;
    }
    
    .btn {
        flex: 1;
        min-width: 120px;
    }
    
    .site-logo {
        width: 32px;
        height: 32px;
    }
    
    .site-title {
        font-size: var(--text-base);
    }
}

/* Large Screens */
@media (min-width: 1400px) {
    .image-display {
        min-height: 600px;
    }
}

/* ============================================
   Utility Classes
   ============================================ */

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

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

.mb-lg {
    margin-bottom: var(--space-lg);
}

.hidden {
    display: none;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}