:root {
    --bs-font-sans-serif: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans", "Liberation Sans", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";

    /* Light Theme */
    --background-primary: #f5f9fc;
    --background-secondary: #e0e7ed;
    /* Light blue-gray */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --accent-color: #0d9488;
    /* Teal */
    --card-background: #ffffff;
    --card-border: #e2e8f0;
    --nav-background: #115e59;
    /* Medium-dark Teal */
    --nav-text: #f1f5f9;
    --nav-text-hover: #ffffff;
    --primary-color: var(--accent-color);
    --primary-hover: #0f766e;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

html {
    height: 100%;
    scroll-behavior: smooth;
}

body {
    display: flex;
    flex-direction: column;
    min-height: 100%;
    font-family: var(--bs-font-sans-serif);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background: var(--card-background);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
    margin: 0;
}

body.dark-theme {
    /* Dark Theme */
    --background-primary: #0f172a;
    --background-secondary: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --accent-color: #2dd4bf;
    /* Brighter Teal */
    --card-background: #1e293b;
    --card-border: #334155;
    --nav-background: #042f2e;
    /* Rich Teal Header */
    --nav-text: #94a3b8;
    --nav-text-hover: #ffffff;
}

main {
    flex-grow: 1;
}

.navbar {
    background-color: var(--nav-background) !important;
    padding: 0.5rem 0;
    /* Slimmer header */
}

.navbar-brand {
    color: #ffffff !important;
    font-weight: 700;
}

.nav-link {
    color: var(--nav-text) !important;
}

.nav-link:hover {
    color: var(--nav-text-hover) !important;
}

.theme-switcher-btn {
    background: transparent;
    border: none;
    color: var(--nav-text);
    font-size: 1.2rem;
    cursor: pointer;
    transition: color 0.3s;
}

.theme-switcher-btn:hover {
    color: var(--nav-text-hover);
}

.dropdown-menu {
    background-color: var(--card-background);
    border: 1px solid var(--card-border);
    box-shadow: var(--shadow);
}

.dropdown-item {
    color: var(--text-primary) !important;
}

.dropdown-item:hover {
    background-color: var(--background-secondary);
    color: var(--accent-color) !important;
}

.banner-container {
    background: linear-gradient(135deg, #03131B 0%, #02131E 100%);
    height: 340px;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}

.banner-container img {
    height: 100%;
    width: auto;
    filter: drop-shadow(0 10px 15px rgba(0, 0, 0, 0.3));
    /* Slight transition to left and right borders only */
    -webkit-mask-image: linear-gradient(to right, transparent 0%, black 3%, black 97%, transparent 100%);
    mask-image: linear-gradient(to right, transparent 0%, black 3%, black 97%, transparent 100%);
}

.hero-intro {
    padding: 60px 0;
    margin-top: 50px;
    text-align: center;
    background: var(--background-secondary);
}

.hero-intro p {
    font-size: 1.15em;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 30px;
}

.cta-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 16px 32px;
    font-size: 1em;
    font-weight: 500;
    border-radius: 50px;
    text-decoration: none;
    transition: all 0.3s;
    box-shadow: var(--shadow);
}

.cta-button:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
}

section {
    padding: 50px 0;
}

h2 {
    text-align: center;
    font-size: 1.6em;
    margin-bottom: 60px;
    /*position: relative;
    color: var(--text-primary);  Use themed text color - fo */
}

h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--accent-color);
    /* background: var(--primary-color); - fo */
    margin: 20px auto 0;
}

/* --- Features Section --- */
#features {
    padding-top: 160px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
    text-align: center;
}

.feature {
    background: var(--background-primary);
    padding: 30px;
    border-radius: 16px;
    border: 1px solid var(--card-border);
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

.feature:hover {
    transform: translateY(-8px);
}

.feature h2,
.feature h3 {
    text-align: left;
    font-size: 1.1em;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--primary-color);
}

.feature h2::after {
    display: none;
}

.features-grid h2 {
    text-align: center;
}

.feature p {
    color: var(--text-secondary);
}

/* --- How It Works (Screenshot Showcase) --- */
#how-it-works {
    padding: 120px 0 170px 0;
}

/* --- Privacy Section --- */
#local-trust {
    background: var(--background-primary);
    border-radius: 8px;
    padding: 50px 40px;
    margin-bottom: 50px;
    text-align: center;
}

/* --- Developer Section --- */
#developer {
    background: var(--background-secondary);
    border-radius: 8px;
    padding: 60px 20px;
    margin-bottom: 40px;
    text-align: center;
}

#developer p {
    margin-bottom: 20px;
}

@media (max-width: 768px) {
    .hero-intro h2 {
        font-size: 2rem;
    }

    .banner-container {
        height: 200px;
    }

    .banner-container img {
        max-height: 150px;
    }
}