/* ZKPassport - Minimal Dark Theme (Skeleton-inspired) */

/* Inter Font Import */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

/* CSS Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Color Variables (Inverted Zorp + Nostromo hints) */
:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --text-muted: #666666;
    --accent: #00ff41;
    --accent-dim: #00cc33;
    --border: #333333;
    --hover: #222222;
}

/* Typography */
html {
    font-size: 62.5%; /* 10px base for easy rem calculations */
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
    font-size: 1.6rem;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    font-weight: 400;
}

/* Container (Skeleton-inspired) */
.container {
    position: relative;
    width: 100%;
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Typography Scale */
h1 {
    font-size: 4.0rem;
    line-height: 1.2;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

h2 {
    font-size: 2.4rem;
    line-height: 1.25;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 2rem;
    margin-top: 4rem;
}

h3 {
    font-size: 1.8rem;
    line-height: 1.3;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

p {
    margin-bottom: 2rem;
    color: var(--text-secondary);
}

/* Header */
header {
    text-align: center;
    padding: 8rem 0 6rem 0;
}

.tagline {
    font-size: 1.8rem;
    color: var(--text-secondary);
    max-width: 60rem;
    margin: 0 auto;
}

/* Main Sections */
main {
    margin-bottom: 8rem;
}

section {
    margin-bottom: 6rem;
}

/* Download Section */
.download-section {
    text-align: center;
    margin-bottom: 8rem;
}

.download-btn {
    display: inline-block;
    background-color: var(--accent);
    color: var(--bg-primary);
    padding: 1.6rem 3.2rem;
    text-decoration: none;
    font-size: 1.6rem;
    font-weight: 500;
    border-radius: 4px;
    transition: all 0.2s ease;
    margin-bottom: 2rem;
}

.download-btn:hover {
    background-color: var(--accent-dim);
    transform: translateY(-1px);
}

.version-info {
    font-size: 1.4rem;
    color: var(--text-muted);
    margin-bottom: 0;
}

/* Features */
.features {
    display: grid;
    gap: 4rem;
    margin-bottom: 6rem;
}

.feature {
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.feature:last-child {
    border-bottom: none;
}

.feature h3 {
    color: var(--accent);
    margin-bottom: 1rem;
}

.feature p {
    margin-bottom: 0;
}

/* Lists */
ul, ol {
    margin-left: 2rem;
    margin-bottom: 2rem;
}

li {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

ul li {
    list-style-type: none;
    position: relative;
}

ul li::before {
    content: "→";
    color: var(--accent);
    position: absolute;
    left: -2rem;
}

ol li {
    color: var(--text-secondary);
}

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

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

/* Footer */
footer {
    text-align: center;
    padding: 4rem 0 6rem 0;
    border-top: 1px solid var(--border);
    margin-top: 8rem;
}

footer p {
    font-size: 1.4rem;
    color: var(--text-muted);
    margin-bottom: 0;
}

footer a {
    color: var(--text-muted);
}

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

/* Responsive (Mobile-First) */
@media (min-width: 400px) {
    .container {
        padding: 0 30px;
    }
}

@media (min-width: 550px) {
    h1 {
        font-size: 5.0rem;
    }
    
    .tagline {
        font-size: 2.0rem;
    }
    
    .features {
        grid-template-columns: 1fr 1fr;
        gap: 4rem 6rem;
    }
}

@media (min-width: 750px) {
    .container {
        padding: 0 40px;
    }
    
    header {
        padding: 12rem 0 8rem 0;
    }
    
    .tagline {
        font-size: 2.2rem;
    }
}

/* Focus states for accessibility */
.download-btn:focus,
a:focus {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}