/* TERRAPORTERS - Minimal Design Documentation Stylesheet */
/* PC-98 Retro Aesthetic - Hopeful Exploration Theme */
/* Inspired by nature reclaiming civilization */

/* ==================== CSS RESET ==================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

/* ==================== CSS VARIABLES ==================== */
:root {
    /* Backgrounds - Muted earth tones */
    --bg-primary: #c8d0c8;        /* Muted gray-green, like weathered concrete */
    --bg-card: #f0f4f0;            /* Very light gray-green for cards */
    --bg-header: linear-gradient(135deg, #d8e0d8 0%, #c8d4cc 100%);

    /* Accent colors - From hero image */
    --accent-teal: #1de9b6;        /* Bright teleporter glow */
    --accent-green: #6b8e5c;       /* Moss green */
    --accent-green-dark: #4a6741;  /* Darker moss for borders */
    --accent-earth: #8b7355;       /* Earth/wood tones */
    --accent-orange: #ff8c42;      /* Warm orange for warnings */

    /* Text - Dark on light */
    --text-primary: #2a3028;       /* Very dark green-black */
    --text-secondary: #5a6555;     /* Medium green-gray */
    --text-muted: #8a9585;         /* Light green-gray */

    /* Borders */
    --border-light: #c0c8c0;       /* Light green-gray */
    --border-color: #98a898;       /* Medium green-gray */

    /* Interactive */
    --link-color: #0d9b7a;         /* Darker teal for links on light bg */
    --link-hover: #1de9b6;         /* Bright cyan on hover */

    /* Spacing (4 variables) */
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;

    /* Typography (2 variables) */
    --font-heading: 'Courier New', Courier, monospace;
    --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* ==================== BASE STYLES ==================== */
html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    /* Scrolling atmospheric gradient: sky to earth */
    background-image:
        repeating-linear-gradient(0deg, transparent, transparent 2px, rgba(107, 142, 92, 0.03) 2px, rgba(107, 142, 92, 0.03) 4px),
        linear-gradient(180deg, #e0eae0 0%, #c0ccc0 30%, #a8b4a8 70%, #90a090 100%);
    /* Gradient scrolls with content - no fixed attachment */
}

/* Typography */
h1, h2, h3, h4 {
    font-family: var(--font-heading);
    margin-bottom: var(--spacing-md);
    line-height: 1.3;
}

h1 {
    font-size: 2rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--accent-teal);
}

h2 {
    font-size: 1.5rem;
    margin-top: var(--spacing-xl);
    color: var(--accent-green-dark);
}

h3 {
    font-size: 1.2rem;
    color: var(--accent-green);
    margin-top: var(--spacing-lg);
}

h4 {
    font-size: 1rem;
    color: var(--text-secondary);
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

/* Links */
a {
    color: var(--link-color);
    text-decoration: none;
    transition: color 0.2s ease, text-shadow 0.2s ease;
    font-weight: 500;
}

a:hover {
    color: var(--link-hover);
    text-shadow: 0 0 8px rgba(29, 233, 182, 0.3);
}

/* Lists */
ul, ol {
    margin-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

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

/* ==================== LAYOUT ==================== */
header {
    background: transparent;
    border-bottom: 2px solid var(--border-color);
    padding: var(--spacing-lg) var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

header h1 {
    margin: 0;
    font-size: 1.5rem;
    color: var(--text-primary);
    letter-spacing: 0.03em;
}

header .tagline {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-top: 0.25rem;
    font-weight: 400;
}

header nav {
    margin-top: var(--spacing-md);
}

header nav a {
    margin-right: var(--spacing-lg);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
}

main {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl) var(--spacing-xl);
}

footer {
    background: var(--bg-header);
    border-top: 2px solid var(--accent-green);
    padding: var(--spacing-lg) var(--spacing-xl);
    margin-top: var(--spacing-xl);
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
    box-shadow: 0 -2px 8px rgba(74, 103, 65, 0.08);
}

/* ==================== NAVIGATION SIDEBAR ==================== */
#nav-sidebar {
    position: fixed;
    left: var(--spacing-lg);
    top: 140px;
    width: 220px;
    max-height: calc(100vh - 180px);
    overflow-y: auto;
    z-index: 100;
}

#table-of-contents {
    background-color: var(--bg-card);
    border: 1px solid var(--border-light);
    border-left: 4px solid var(--accent-teal);
    border-radius: 6px;
    padding: var(--spacing-md);
    box-shadow: 0 2px 8px rgba(74, 103, 65, 0.08);
}

#table-of-contents h3 {
    margin: 0 0 var(--spacing-md) 0;
    font-size: 0.9rem;
    color: var(--accent-green-dark);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

#nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

#nav-list li {
    margin-bottom: 0.25rem;
}

#nav-list a {
    display: block;
    padding: 0.4rem 0.5rem;
    font-size: 0.8rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.2s ease;
    line-height: 1.3;
}

#nav-list a:hover {
    color: var(--link-hover);
    background-color: rgba(29, 233, 182, 0.05);
    transform: translateX(2px);
    text-shadow: none;
}

#nav-list a.active {
    color: var(--link-color);
    background-color: rgba(29, 233, 182, 0.08);
    font-weight: 600;
    border-left: 2px solid var(--accent-teal);
    padding-left: calc(0.5rem - 2px);
}

/* ==================== COMPONENTS ==================== */

/* Hero Image */
.hero {
    width: 100%;
    height: auto;
    border-radius: 8px;
    border: 3px solid var(--accent-teal);
    margin-bottom: var(--spacing-xl);
    display: block;
    box-shadow: 0 4px 16px rgba(29, 233, 182, 0.15);
}

/* Card - Content Container */
.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-light);
    border-left: 4px solid var(--accent-green);
    border-radius: 6px;
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    box-shadow: 0 2px 8px rgba(74, 103, 65, 0.08);
    transition: box-shadow 0.3s ease, transform 0.2s ease;
    scroll-margin-top: 120px; /* Offset for header height when jumping to sections */
}

.card:hover {
    box-shadow: 0 4px 16px rgba(74, 103, 65, 0.12);
    transform: translateY(-2px);
}

.card h2:first-child {
    margin-top: 0;
}

/* TBD Note */
.tbd-note {
    background-color: rgba(255, 140, 66, 0.08);
    border-left: 4px solid var(--accent-orange);
    border-radius: 4px;
    padding: var(--spacing-md);
    margin: var(--spacing-md) 0;
    font-style: italic;
    color: var(--text-secondary);
    box-shadow: 0 1px 4px rgba(255, 140, 66, 0.1);
}

.tbd-list {
    list-style-type: none;
    margin-left: 0;
}

.tbd-list li {
    color: var(--text-primary);
}

.tbd-list li::before {
    content: "⚠ ";
    color: var(--accent-orange);
    font-weight: bold;
}

/* ==================== RESPONSIVE ==================== */

/* Hide sidebar on tablets and smaller */
@media (max-width: 1200px) {
    #nav-sidebar {
        display: none;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }

    header {
        padding: var(--spacing-md);
    }

    header h1 {
        font-size: 1.5rem;
    }

    header nav a {
        display: block;
        margin-bottom: var(--spacing-sm);
    }

    main {
        padding: 0 var(--spacing-md) var(--spacing-md);
    }

    .card {
        padding: var(--spacing-md);
    }

    h1 {
        font-size: 1.6rem;
    }

    h2 {
        font-size: 1.3rem;
    }
}