/* Reset & Box-Sizing */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* Light Mode Colors */
    --text-color: #042069; /* Dark Blue */
    --background-color: #e3e7f0; /* Light Grayish Blue */
    --accent-color: #FFA500; /* Marigold */
    --light-accent-color: #FFC04D; /* Lighter Orange for hover/active states */
    --border-color: #b0c4de; /* Light Steel Blue for borders */
    --card-background: #ffffff; /* White for content cards */

    /* Dark Mode Colors */
    --dark-text-color: #e3e7f0; /* Light Grayish Blue */
    --dark-background-color: #1a1a2e; /* Deep Dark Blue */
    --dark-accent-color: #ffda00; /* Gold dark mode contrast */
    --dark-light-accent-color: #ffe54c;
    --dark-border-color: #3f3e5b;
    --dark-card-background: #2a2a4a;

    /* Font Families */
    --font-heading: 'Roboto', sans-serif;
    --font-body: 'Fjord One', serif;

    /* Base font size for responsiveness */
    --base-font-size: clamp(16px, 1.2vw + 1rem, 18px); /* Min 16px, Preferred relative to viewport, Max 18px */

    /* Bookmark shape variables */
    --bookmark-cutout-size: 8px; /* Slightly smaller cutout for smaller nav items */
}

/* Base Body Styles */
body {
    font-family: var(--font-body);
    color: var(--text-color);
    background-color: var(--background-color);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease; /* Smooth transition for dark mode */
    font-size: var(--base-font-size); /* Apply base font size */

    display: flex; /* For sticky footer */
    flex-direction: column; /* For sticky footer */
    min-height: 100vh; /* Ensure body takes at least full viewport height */
    overflow-x: hidden; /* Prevent horizontal scroll when menu is off-screen */
}

/* Prevents scrolling when menu is open */
body.no-scroll {
    overflow: hidden;
}

/* Dark Mode Styles */
body.dark-mode {
    color: var(--dark-text-color);
    background-color: var(--dark-background-color);
}

body.dark-mode .site-header {
    background-color: var(--dark-background-color);
    border-bottom-color: var(--dark-border-color);
}

body.dark-mode .header-top {
    background-color: var(--dark-background-color);
    border-bottom-color: var(--dark-border-color); /* This specific border might not be needed after flex changes */
}

body.dark-mode .main-nav-overlay {
    background-color: rgba(26, 26, 46, 0.95); /* Semi-transparent dark background */
}

body.dark-mode .site-branding h1,
body.dark-mode .site-branding .tagline {
    color: var(--dark-text-color);
}

body.dark-mode .main-nav ul li a {
    color: var(--dark-text-color); /* Text color for nav items in dark mode */
}

body.dark-mode .main-nav ul li a:hover::before,
body.dark-mode .main-nav ul li a.active::before {
    background-color: var(--dark-accent-color); /* Bookmark background color in dark mode */
}

body.dark-mode .main-nav ul li a:hover,
body.dark-mode .main-nav ul li a.active {
    color: var(--dark-background-color); /* Text matches dark mode background when highlighted */
}

body.dark-mode .site-footer {
    background-color: var(--dark-background-color);
    color: var(--dark-text-color);
    border-top-color: var(--dark-border-color);
}

body.dark-mode .content-section {
    background-color: var(--dark-card-background);
    border-color: var(--dark-border-color);
    color: var(--dark-text-color);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

body.dark-mode .content-section h2 {
    color: var(--dark-accent-color);
}

body.dark-mode h3 {
    color: var(--dark-accent-color);
    border-bottom-color: var(--dark-border-color);
}


/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--text-color);
    margin-bottom: 0.8em;
    line-height: 1.2;
}

/* Fluid Font Sizes for Headings */
h1 {
    font-size: clamp(1.8em, 4.5vw, 3em);
    font-weight: 700;
    margin-bottom: 0em;
}

.tagline {
    font-family: var(--font-body);
    font-size: clamp(0.8em, 1.8vw, 1.0em);
    color: var(--text-color);
    margin-top: 0;
    margin-bottom: 0.5em;
}

h2 {
    font-size: clamp(1.8em, 4vw, 2.5em);
}

h3 {
    font-family: var(--font-heading);
    font-size: clamp(1.2em, 2.5vw, 1.8em);
    color: var(--accent-color);
    margin-top: 1.5em;
    margin-bottom: 0.8em;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.2em;
}

p {
    margin-bottom: 1em;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover, a:focus {
    color: var(--light-accent-color);
    text-decoration: underline;
}

/* Layout - Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header General Styles */
.site-header {
    width: 100%;
    background-color: var(--background-color);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    transition: background-color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    display: flex; /* Make header itself a flex container */
    flex-direction: column; /* Stack header-top and any other header elements */
    align-items: center; /* Center horizontally by default */
}

.header-top {
    padding: 10px 15px;
    display: flex;
    justify-content: center; /* Default to center */
    align-items: center;
    width: 100%; /* Take full width to allow internal centering */
}

.site-branding {
    text-align: center; /* Default to center */
    flex-grow: 0; /* Remove flex-grow */
    margin: 0 auto; /* Center with auto margins */
    margin-bottom: 0px;
}

/* NEW - Adjust for hamburger on mobile (up to 767px) */
@media (max-width: 767px) {
    .header-top {
        justify-content: space-between; /* Push branding left, hamburger right */
    }
    .site-branding {
        text-align: left; /* Align branding left on mobile */
        margin: 0; /* Remove auto margins when space-between is used */
    }
}

/* NEW: Hamburger Menu Toggle Button */
.hamburger-menu-toggle {
    display: flex; /* Always show hamburger by default (mobile-first) */
    flex-direction: column;
    justify-content: space-around;
    width: 30px;
    height: 25px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001; /* Above everything else */
    position: relative; /* For the bar animations */
}

.hamburger-menu-toggle .bar {
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--text-color); /* Color of the bars */
    border-radius: 5px;
    transition: all 0.3s ease-in-out;
}

/* Dark mode for hamburger bars */
body.dark-mode .hamburger-menu-toggle .bar {
    background-color: var(--dark-text-color);
}

/* Animation for close button (X shape) */
.hamburger-menu-toggle.open .bar:nth-child(1) {
    transform: translateY(11px) rotate(45deg);
}
.hamburger-menu-toggle.open .bar:nth-child(2) {
    opacity: 0;
}
.hamburger-menu-toggle.open .bar:nth-child(3) {
    transform: translateY(-11px) rotate(-45deg);
}

/* NEW: Main Navigation Overlay (hidden by default) */
.main-nav-overlay {
    position: fixed; /* Fixed to viewport */
    top: 0;
    left: -100%; /* Start off-screen to the left */
    width: 100%;
    height: 100vh; /* Full viewport height */
    background-color: rgba(227, 231, 240, 0.95); /* Semi-transparent background */
    z-index: 1000; /* Below hamburger, above content */
    transition: left 0.4s ease-in-out; /* Smooth slide in/out */
    display: flex; /* To center/align nav content */
    align-items: flex-start; /* Align nav to top (left-aligned from design) */
    padding-top: 60px; /* Space for the header above it */
    overflow-y: auto; /* Enable scrolling for long menus on small screens */
    box-shadow: 2px 0 10px rgba(0,0,0,0.2);
}

/* When menu is open */
.main-nav-overlay.open {
    left: 0; /* Slide into view */
}

/* Main Navigation (inside the overlay) */
.main-nav { /* This is the <nav class="main-nav container"> */
    display: flex; /* Make it a flex container */
    justify-content: flex-start; /* Align contents to the start */
    align-items: flex-start; /* Align contents to the top */
    padding-top: 20px; /* Add top padding here */
    padding-bottom: 20px; /* Add bottom padding here */
    padding-left: 15px; /* Add left padding to indent the entire menu */
    width: auto; /* Allow the nav to shrink to its content width */
}

.main-nav ul {
    list-style: none;
    display: flex;
    flex-direction: column; /* Stack vertically for mobile menu */
    justify-content: flex-start; /* Align items to the start (left) */
    align-items: flex-start; /* Align items to the start (left) */
    padding: 0; /* Removed padding here, it's now on .main-nav */
    margin: 0;
    width: auto; /* Allow the ul to shrink to its content */
}

.main-nav ul li {
    margin: 10px 0; /* More margin between vertical list items */
    width: 100%; /* Full width for clickable area within the flexible nav */
}

.main-nav ul li a {
    font-family: var(--font-heading);
    font-size: clamp(1em, 2.5vw, 1.2em); /* Slightly larger font for mobile links */
    color: var(--text-color);
    padding: 8px 15px; /* Keep this padding as it's part of the clickable area */
    display: block;
    position: relative;
    z-index: 1;
    text-decoration: none;
    transition: color 0.2s ease;
    overflow: hidden;
    white-space: nowrap;
    text-align: left; /* Ensure text is left-aligned */
}

/* Bookmark Highlight using ::before pseudo-element and clip-path */
/* Minor adjustments for vertical menu */
.main-nav ul li a::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--light-accent-color);
    z-index: -1;
    transition: background-color 0.2s ease, transform 0.3s ease, clip-path 0.3s ease;

    /* Maintain bookmark shape, but for full width item */
    clip-path: polygon(
        0% 0%,
        100% 0%,
        100% calc(100% - var(--bookmark-cutout-size)),
        50% 100%,
        0% calc(100% - var(--bookmark-cutout-size))
    );
    transform: translateX(-100%); /* Start off-screen to the left */
    opacity: 0;
}

/* Hover and Active states for the bookmark highlight */
.main-nav ul li a:hover::before,
.main-nav ul li a.active::before {
    transform: translateX(0); /* Slide in from left */
    opacity: 1;
    background-color: var(--accent-color);
}

/* Highlighted text color */
.main-nav ul li a:hover,
.main-nav ul li a.active {
    color: var(--background-color); /* Text matches page background when highlighted */
    background-color: transparent;
    border-radius: 0;
}


/* Main Content Area */
.site-content {
    flex-grow: 1;
    padding: 40px 0;
}

.content-section {
    background-color: var(--card-background);
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    padding: 30px;
    margin-bottom: 30px;
    border: 1px solid var(--border-color);
}

.content-section h2 {
    color: var(--accent-color);
}

/* Footer Styles */
.site-footer {
    background-color: var(--background-color);
    color: var(--text-color);
    text-align: center;
    padding: 20px 0;
    border-top: 1px solid var(--border-color);
    font-size: 0.9em;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.site-footer .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.footer-line {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    width: 100%;
    gap: 10px;
}

.footer-line p {
    margin: 0;
}

/* Dark Mode Toggle Button in Footer */
.dark-mode-toggle {
    background: none;
    border: none;
    font-size: 1.8em;
    cursor: pointer;
    padding: 5px;
    transition: transform 0.2s ease;
    color: inherit;
    outline: none;
}

.dark-mode-toggle:hover {
    transform: scale(1.1);
}

.dark-mode-toggle:focus-visible {
    outline: none;
}


/* Responsive Adjustments (Desktop/Tablet) - for the full menu */
@media (min-width: 768px) {
    .site-header {
        /* On desktop, allow header to center its direct children (header-top, main-nav-overlay) */
        flex-direction: column; /* Keep column for structure, but content will center */
    }

    .header-top {
        padding: 10px 15px;
        justify-content: center; /* Explicitly center content on desktop */
    }

    .site-branding {
        text-align: center;
        margin: 0 auto; /* Ensure it's centered on desktop */
    }

    /* Hide hamburger on desktop */
    .hamburger-menu-toggle {
        display: none;
    }

    /* Display full navigation on desktop */
    .main-nav-overlay {
        position: static; /* Remove fixed positioning */
        background-color: transparent; /* Remove background overlay */
        height: auto; /* Remove fixed height */
        width: 100%; /* Take full width */
        padding-top: 0;
        box-shadow: none;
        display: block; /* Ensure it's visible */
        left: auto; /* Reset left property */
        transition: none; /* No transition on desktop */
    }

    .main-nav { /* This nav already has container, so it will center */
        display: flex; /* Ensure flex behavior */
        justify-content: center; /* Center navigation items horizontally */
        align-items: center;
        padding: 0; /* Remove padding from .main-nav for desktop */
        width: auto; /* Allow it to shrink to content */
    }

    .main-nav ul {
        flex-direction: row; /* Display horizontally */
        justify-content: center; /* Center navigation items within the ul */
        align-items: center;
        padding: 5px 0; /* Smaller padding for horizontal menu */
        margin: 0 auto; /* Center the ul itself */
        width: auto; /* Adjust width to content */
        max-width: none; /* Remove max-width constraint */
    }

    .main-nav ul li {
        margin: 3px 5px; /* Margins for horizontal items */
        width: auto; /* Auto width */
    }

    .main-nav ul li a {
        font-size: clamp(0.85em, 1.6vw, 1.0em); /* Smaller font for horizontal links */
        padding: 6px 10px; /* Smaller padding */
        text-align: center; /* Center text if needed */
    }

    /* Bookmark highlight for desktop, slide in from bottom */
    .main-nav ul li a::before {
        transform: translateY(100%); /* Slide in from bottom for desktop */
        clip-path: polygon(
            0% 0%,
            100% 0%,
            100% calc(100% - var(--bookmark-cutout-size)),
            50% 100%,
            0% calc(100% - var(--bookmark-cutout-size))
        );
    }
    .main-nav ul li a:hover::before,
    .main-nav ul li a.active::before {
        transform: translateY(0);
    }

    .footer-line {
        justify-content: center;
    }

    .footer-line p {
        margin-right: 15px;
    }
}