/* General Styles & Theme Variables (Consistent with main style.css) */
:root {
    /* Color Palette - Default Dark Theme */
    --primary-color: #8A2BE2;       /* Purple */
    --secondary-color: #4A90E2;     /* Blue */
    --accent-color-deep: #2a0a4a;   /* Deep purple for gradients */

    --bg-main: #10101f;             /* Darkest background */
    --bg-content: #1a1a2e;          /* Main content background */
    --bg-card: #2c2c44;             /* Card and elevated element background */

    --text-primary: #ffffff;        /* Primary text (headings, bright text) */
    --text-secondary: #e0e0e0;      /* Secondary text (paragraphs) */
    --text-muted: #a0a0c0;          /* Muted text, subtitles */

    --border-color: rgba(255, 255, 255, 0.1);
    --shadow-color: rgba(0, 0, 0, 0.4); /* Darker shadow for dark theme */

    --header-bg: rgba(26, 26, 46, 0.6);
    --nav-dropdown-bg: rgba(44, 44, 68, 0.85); /* For mobile dropdown */
    --btn-primary-shadow: rgba(138, 43, 226, 0.4);
    --btn-secondary-border: var(--secondary-color);
    
    --switcher-bg: #2c2c44;
    --switcher-icon-color: var(--primary-color);
    --switcher-shadow: rgba(0, 0, 0, 0.2);

    --font-family: 'Poppins', sans-serif;
}

body.light-theme {
    /* Light Theme Overrides */
    --primary-color: #7A1BD9;
    --secondary-color: #3A80D2;
    --accent-color-deep: #D1C4E9;

    --bg-main: #f4f6f8;
    --bg-content: #ffffff;
    --bg-card: #ffffff;

    --text-primary: #222222;
    --text-secondary: #555555;
    --text-muted: #777777;

    --border-color: rgba(0, 0, 0, 0.1);
    --shadow-color: rgba(0, 0, 0, 0.1); /* Lighter shadow for light theme */

    --header-bg: rgba(255, 255, 255, 0.7);
    --nav-dropdown-bg: rgba(245, 245, 245, 0.9); /* For mobile dropdown */
    --btn-primary-shadow: rgba(122, 27, 217, 0.3);
    
    --switcher-bg: #ffffff;
    --switcher-shadow: rgba(0, 0, 0, 0.15);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: var(--font-family);
    background-color: var(--bg-main);
    color: var(--text-secondary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-tap-highlight-color: transparent;
    transition: background-color 0.3s ease, color 0.3s ease;
    position: relative; /* For canvas positioning */
}

.container { width: 90%; max-width: 1200px; margin: 0 auto; padding: 0 15px; }

h1, h2, h3 { color: var(--text-primary); margin-bottom: 0.8em; }
h2 { font-size: 2.5rem; text-align: center; margin-bottom: 1.5em; }
a { color: var(--secondary-color); text-decoration: none; }

/* New Subheading Style */
.section-subheading-left {
    text-align: left;
    font-size: 1.75rem; /* Adjust size as needed, smaller than h2 */
    color: var(--text-primary); /* Or --text-secondary for less emphasis */
    margin-bottom: 1.2em; /* Space before the grid */
    font-weight: 600; /* Or 500 for less bold */
}

/* Meteor Trails Canvas */
#meteor-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1; /* Behind all content */
    pointer-events: none; /* Allow clicks to pass through */
}

/* Header */
.header {
    position: fixed; 
    left: 0; top: 0; width: 100%; z-index: 1000;
    padding: 15px 0;
    background: var(--header-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.3s ease;
}
.header-main { display: flex; align-items: center; justify-content: space-between; }
.logo-link { 
    font-size: 1.8rem; /* Kept for potential fallback if images fail, but images will dictate size */
    font-weight: 700; 
    color: var(--text-primary); 
    display: inline-block; /* Important for wrapping img tags */
    line-height: 0; /* Prevents extra space if text node exists or due to inline-block nature */
}
.logo-link .logo-image {
    vertical-align: middle; /* Good for alignment */
}

/* Logo Theming - START */
.logo-link .logo-light {
    display: none; /* Hidden by default */
}
.logo-link .logo-dark {
    display: inline; /* Shown by default (for dark theme) */
}

body.light-theme .logo-link .logo-light {
    display: inline; /* Show in light theme */
}
body.light-theme .logo-link .logo-dark {
    display: none; /* Hide in light theme */
}
/* Logo Theming - END */


/* Navigation - Desktop (portfolio-nav) & Mobile (nav-toggler, .nav) */
.portfolio-nav ul { 
    list-style: none;
    display: flex; 
    margin: 0;
    padding: 0;
}
.portfolio-nav li {
    margin-left: 25px;
}
.portfolio-nav a { 
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.3s ease;
    display: block;
    padding: 10px 0; 
    position: relative;
}
.portfolio-nav a:hover {
    color: var(--primary-color);
}

/* Hamburger Toggle Button Styles */
.nav-toggler {
    height: 34px;
    width: 40px;
    border: none;
    background-color: transparent;
    display: none; 
    cursor: pointer;
    z-index: 1001; 
}
.nav-toggler span {
    display: block;
    height: 2px;
    width: 24px;
    background-color: var(--text-primary);
    margin: auto;
    position: relative;
    transition: background-color 0.3s ease;
}
.nav-toggler.active span {
    background-color: transparent;
}
.nav-toggler span::before,
.nav-toggler span::after {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--text-primary);
    transition: top 0.2s ease 0.2s, transform 0.2s ease;
}
.nav-toggler span::before { top: -7px; }
.nav-toggler span::after { top: 7px; }
.nav-toggler.active span::before { top: 0; transform: rotate(45deg); transition-delay: 0s, 0.2s; }
.nav-toggler.active span::after { top: 0; transform: rotate(-45deg); transition-delay: 0s, 0.2s; }

/* Portfolio Main Content Area */
.portfolio-main {
    padding-top: 100px; 
}

/* Portfolio Intro Section */
.portfolio-intro-section {
    min-height: 60vh; 
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 60px 20px;
    position: relative; 
    background-color: transparent; 
    opacity: 0; /* Initially hidden, JS and .is-visible will manage this */
    transition: opacity 0.6s ease-out; /* Smooth transition for opacity changes by JS or class */
}
.portfolio-intro-section.is-visible {
    opacity: 1; /* Made visible by IntersectionObserver */
}
.intro-headline, .intro-subheadline {
    opacity: 0; 
    transform: translateY(20px);
    /* Children fade in after parent's .is-visible is applied */
    transition: opacity 0.8s ease-out 0.2s, transform 0.8s ease-out 0.2s; 
}
.portfolio-intro-section.is-visible .intro-headline,
.portfolio-intro-section.is-visible .intro-subheadline {
    opacity: 1;
    transform: translateY(0);
}
.intro-headline {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5em;
}
.intro-subheadline {
    font-size: 1.3rem;
    max-width: 700px;
    margin: 0 auto;
    color: var(--text-muted);
}

/* Portfolio Grid Section */
.portfolio-grid-section {
    padding: 80px 0;
    background-color: var(--bg-content); 
}
.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}
.portfolio-item {
    background-color: var(--bg-card);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 8px 25px var(--shadow-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
}
.portfolio-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 35px var(--shadow-color);
}
.portfolio-item-image-wrapper {
    width: 100%;
    padding-top: 60%; 
    position: relative;
    overflow: hidden;
}
.portfolio-item-image-wrapper img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}
.portfolio-item:hover .portfolio-item-image-wrapper img {
    transform: scale(1.05);
}
.portfolio-item-content {
    padding: 25px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}
.portfolio-item-content h3 {
    font-size: 1.6rem;
    color: var(--text-primary);
    margin-bottom: 0.5em;
}
.project-category {
    font-size: 0.9rem;
    color: var(--secondary-color);
    font-weight: 500;
    margin-bottom: 1em;
    text-transform: uppercase;
}
.project-description {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5em;
    flex-grow: 1;
}
.project-link {
    margin-top: auto; 
    align-self: flex-start; 
}

/* Buttons */
.btn {
    padding: 10px 24px;
    border-radius: 50px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    border: none;
    cursor: pointer;
    font-size: 0.95rem;
    text-align: center;
}
.btn-secondary {
    background-color: transparent;
    color: var(--text-primary);
    border: 2px solid var(--btn-secondary-border);
}
.btn-secondary:hover {
    background-color: var(--secondary-color);
    color: var(--bg-main); 
}

/* Footer */
.footer {
    background-color: var(--bg-main);
    color: var(--text-muted);
    text-align: center;
    padding: 30px 0;
    border-top: 1px solid var(--border-color);
}

/* Theme Switcher Button */
.theme-switcher {
    position: fixed; bottom: 25px; right: 25px;
    width: 50px; height: 50px; border-radius: 50%;
    background-color: var(--switcher-bg);
    color: var(--switcher-icon-color);
    border: none; box-shadow: 0 4px 12px var(--switcher-shadow);
    cursor: pointer; display: flex; align-items: center; justify-content: center;
    z-index: 1001;
    transition: background-color 0.3s ease, color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
    overflow: hidden; font-size: 1.5rem;
}
.theme-switcher:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 16px var(--switcher-shadow);
}
.theme-switcher .icon-moon,
.theme-switcher .icon-sun {
    position: absolute;
    transition: opacity 0.3s ease, transform 0.3s ease;
}
body:not(.light-theme) .theme-switcher .icon-moon { opacity: 0; transform: scale(0); }
body:not(.light-theme) .theme-switcher .icon-sun { opacity: 1; transform: scale(1); }
body.light-theme .theme-switcher .icon-moon { opacity: 1; transform: scale(1); }
body.light-theme .theme-switcher .icon-sun { opacity: 0; transform: scale(0); }

/* Responsive Adjustments */
@media (max-width: 991px) {
    /* Mobile Navigation Styles */
    .nav.portfolio-nav ul { 
        flex-direction: column;
        width: 100%;
        background-color: var(--nav-dropdown-bg);
        backdrop-filter: blur(8px);
        -webkit-backdrop-filter: blur(8px);
        border-radius: 0 0 10px 10px;
        box-shadow: 0 5px 15px var(--shadow-color);
        overflow: hidden;
        position: absolute; 
        right: 0;
        top: 100%; 
        margin-top: 12px; 
        max-width: 300px; 
        visibility: hidden; 
        opacity: 0;
        transform: translateY(-10px);
        transition: opacity 0.3s ease, transform 0.3s ease, visibility 0s ease 0.3s;
    }

    .nav.portfolio-nav.active ul { 
        visibility: visible;
        opacity: 1;
        transform: translateY(0);
        transition-delay: 0s;
    }
    
    .nav.portfolio-nav li { 
        margin-left: 0;
        text-align: left;
        border-bottom: 1px solid var(--border-color);
        transform: translateY(20px);
        opacity: 0;
        transition: opacity 0.4s ease, transform 0.4s ease;
        transition-delay: calc(0.05s * var(--item)); 
    }
    .nav.portfolio-nav.active li {
        opacity: 1;
        transform: translateY(0);
    }
    .nav.portfolio-nav li:last-child {
        border-bottom: none;
    }
    .nav.portfolio-nav a { 
        padding: 15px 25px;
        width: 100%;
    }
    .nav.portfolio-nav a::before { 
        display: none;
    }

    .nav-toggler {
        display: block; 
        margin-left: auto; 
    }
    
    .intro-headline { font-size: 2.8rem; }
    .intro-subheadline { font-size: 1.1rem; }
}

@media (max-width: 768px) {
    .portfolio-main { padding-top: 80px; }
    .intro-headline { font-size: 2.2rem; }
    .portfolio-grid { grid-template-columns: 1fr; } 
    .theme-switcher { width: 45px; height: 45px; font-size: 1.3rem; bottom: 20px; right: 20px; }
    .section-subheading-left { font-size: 1.5rem; } /* Adjust for smaller screens */
}