:root {
    /* Ice Blue Theme Variables */
    --primary-color: #87CEEB; /* Sky Blue / Ice Blue */
    --primary-dark: #4682B4;  /* Steel Blue */
    --secondary-color: #B0E0E6; /* Powder Blue */
    --accent-color: #00BFFF; /* Deep Sky Blue */
    
    --bg-color: #FFFFFF;
    --bg-secondary: #F0F8FF; /* Alice Blue */
    --text-color: #2F4F4F; /* Dark Slate Gray */
    --text-light: #778899; /* Light Slate Gray */
    
    --card-bg: #FFFFFF;
    --card-shadow: 0 4px 6px rgba(135, 206, 235, 0.2);
    --card-hover-shadow: 0 10px 20px rgba(135, 206, 235, 0.4);
    
    --font-main: 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    --transition-speed: 0.3s;
    --border-radius: 12px;
    --bg-overlay: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] {
    --bg-color: #121212;
    --bg-secondary: #1E1E1E;
    --text-color: #E0E0E0;
    --text-light: #A0A0A0;
    
    --card-bg: #2C2C2C;
    --card-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --card-hover-shadow: 0 10px 20px rgba(135, 206, 235, 0.15);
    --bg-overlay: rgba(18, 18, 18, 0.95);
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow-x: hidden;
    line-height: 1.6;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: var(--text-color);
    margin-bottom: 1rem;
    font-weight: 600;
}

h1 { font-size: 3rem; }
h2 { font-size: 2.5rem; text-align: center; margin-bottom: 3rem; position: relative; }
h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    margin: 10px auto 0;
    border-radius: 2px;
}

h3 { font-size: 1.5rem; margin-bottom: 0.5rem; }
h4 { font-size: 1.2rem; margin-bottom: 0.5rem; color: var(--primary-dark); }
[data-theme="dark"] h4 { color: var(--primary-color); }

a {
    text-decoration: none;
    color: var(--primary-dark);
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--accent-color);
}

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

section {
    padding: 80px 0;
}

section:nth-child(even) {
    background-color: var(--bg-secondary);
}

/* Header & Navigation */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    transition: background-color var(--transition-speed);
}

[data-theme="dark"] header {
    background-color: rgba(18, 18, 18, 0.9);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-dark);
}

[data-theme="dark"] .logo {
    color: var(--primary-color);
}

.nav-links {
    display: flex;
    gap: 30px;
    list-style: none;
}

.nav-links a {
    color: var(--text-color);
    font-weight: 500;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--primary-color);
    transition: width var(--transition-speed);
}

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

.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-color);
    font-size: 1.2rem;
    padding: 8px;
    border-radius: 50%;
    transition: background-color var(--transition-speed);
}

.theme-toggle:hover {
    background-color: var(--bg-secondary);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border-radius: 30px;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
    border: none;
    cursor: pointer;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(70, 130, 180, 0.4);
    color: white;
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-dark);
}

[data-theme="dark"] .btn-outline {
    color: var(--primary-color);
}

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

/* Card Style */
.card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--card-shadow);
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--card-hover-shadow);
}

/* Footer */
footer {
    background-color: var(--text-color);
    color: white;
    padding: 50px 0 20px;
    text-align: center;
    transition: background-color var(--transition-speed);
}

[data-theme="dark"] footer {
    background-color: #0a0a0a; /* Darker background for dark mode */
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-content {
    margin-bottom: 30px;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    opacity: 0.8;
    transition: opacity var(--transition-speed);
}

.social-links a:hover {
    opacity: 1;
}

.copyright {
    opacity: 0.6;
    font-size: 0.9rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 20px;
}

/* Utilities for Knowledge Section */
.icon-inline {
    vertical-align: middle;
    margin-right: 8px;
    color: var(--primary-dark);
}

[data-theme="dark"] .icon-inline {
    color: var(--primary-color);
}

.mb-30 { margin-bottom: 30px; }
.mt-20 { margin-top: 20px; }

.grid-2-cols {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.grid-3-cols {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 20px;
}

.code-block {
    background-color: var(--bg-secondary);
    padding: 15px;
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
    color: var(--text-color);
}

.highlight {
    background-color: rgba(135, 206, 235, 0.2);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--primary-dark);
}

[data-theme="dark"] .highlight {
    color: var(--primary-color);
    background-color: rgba(135, 206, 235, 0.1);
}

.filing-info a {
    color: white;
    text-decoration: none;
    transition: opacity 0.2s;
}

.filing-info a:hover {
    text-decoration: underline;
    opacity: 1;
}

/* Timeline specific (moved from inline) */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}
.timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--primary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
    border-radius: 2px;
}
.timeline-item {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
    box-sizing: border-box;
}
.timeline-item:nth-child(odd) {
    left: 0;
    text-align: right;
}
.timeline-item:nth-child(even) {
    left: 50%;
    text-align: left;
}
.timeline-item::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: var(--bg-color);
    border: 4px solid var(--accent-color);
    top: 15px;
    border-radius: 50%;
    z-index: 1;
}
.timeline-item:nth-child(even)::after {
    left: -10px;
}