:root {
    --primary-color: #4C8DF6; /* BlueElectric from Android */
    --text-main: #E3E3E3; /* Gray100 */
    --text-sub: #C4C7C5; /* Gray300 */
    --text-tertiary: #8E918F; /* Gray500 */
    --bg-color: #101010; /* Gray950 - App Background */
    --surface-color: #1E1F20; /* Gray900 */
    --surface-variant: #222326; /* Gray850 */
    --border-color: #444746; /* Gray600 */
    --max-width: 1200px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-main);
    background-color: var(--bg-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
header {
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-main);
    text-decoration: none;
    letter-spacing: -0.025em;
}

.logo span {
    color: var(--primary-color);
    font-family: 'SF Mono', 'Fira Code', monospace;
}

.logo .divider {
    font-weight: 200;
    margin: 0 8px;
    color: var(--text-tertiary);
}

.nav-link {
    font-size: 0.85rem;
    color: var(--text-sub);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Brand Font */
.brand-font {
    font-family: 'SF Mono', 'Fira Code', monospace;
}

/* Main Content */
main {
    flex: 1;
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 3rem 2rem;
}

.content-card {
    background: transparent;
    border: none;
    border-radius: 0;
    padding: 0;
    box-shadow: none;
}

h1 {
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    color: var(--text-main);
    letter-spacing: -0.025em;
}

h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-main);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

h2.no-border {
    border-bottom: none;
    padding-bottom: 0;
}

h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-main);
}

p {
    margin-bottom: 1rem;
    color: var(--text-sub);
}

ul, ol {
    margin-bottom: 1rem;
    padding-left: 1.5rem;
    color: var(--text-sub);
}

li {
    margin-bottom: 0.5rem;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

a:hover {
    text-decoration: underline;
}

hr {
    border: 0;
    border-top: 1px solid var(--border-color);
    margin: 0;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 4rem 0;
}

.hero.hero-left {
    text-align: left;
    max-width: 900px;
}

.hero h1 {
    font-size: 2.5rem;
    line-height: 1.2;
    letter-spacing: -1px;
    margin-bottom: 1.5rem;
}

.hero h1.hero-large {
    font-size: 3rem;
}

.hero p {
    font-size: 1.15rem;
    line-height: 1.7;
    max-width: 700px;
    margin: 0 auto 1.5rem;
    color: var(--text-sub);
}

.hero.hero-left p {
    margin: 0 0 2rem 0;
}

/* Buttons */
.btn-primary {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 0.875rem 1.75rem;
    border-radius: 8px;
    font-weight: 600;
    transition: background-color 0.2s;
}

.btn-primary:hover {
    background-color: #3A7DE5;
    text-decoration: none;
}

.btn-outline {
    display: inline-block;
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.875rem 1.75rem;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.2s;
}

.btn-outline:hover {
    background-color: var(--surface-variant);
    border-color: var(--text-tertiary);
    text-decoration: none;
}

.hero-btns {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* Feature Grid */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.feature-item {
    padding: 2rem;
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
}

.feature-item h3 {
    margin-top: 0;
    margin-bottom: 1rem;
    color: var(--text-main);
}

.feature-item p {
    margin-bottom: 0;
    font-size: 0.95rem;
    line-height: 1.7;
    color: var(--text-sub);
}

/* Portfolio Card */
.portfolio-card {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--surface-color);
}

.portfolio-card h3 {
    margin: 0 0 0.5rem 0;
    color: var(--primary-color);
}

.portfolio-card p {
    margin: 0;
}

/* Section */
.section {
    padding: 4rem 0;
}

.section-divider {
    border-top: 1px solid var(--border-color);
}

/* Highlight Text */
.highlight {
    color: var(--primary-color);
}

.code-text {
    color: var(--primary-color);
    font-family: 'SF Mono', 'Fira Code', monospace;
    font-weight: 600;
}

/* Quote Section */
.quote-section {
    padding: 5rem 2rem;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.quote-section p {
    font-size: 1.35rem;
    font-weight: 300;
    letter-spacing: -0.5px;
    color: var(--text-tertiary);
    max-width: 800px;
    margin: 0 auto;
}

.quote-section strong {
    color: var(--text-main);
    font-weight: 600;
}

/* Footer */
footer {
    background-color: var(--bg-color);
    border-top: 1px solid var(--border-color);
    padding: 3rem 0;
    margin-top: auto;
}

.footer-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    font-size: 0.875rem;
}

.footer-section h4 {
    color: var(--text-main);
    font-weight: 600;
    margin-bottom: 1rem;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
}

.footer-section p, .footer-section a {
    color: var(--text-sub);
    display: block;
    margin-bottom: 0.5rem;
}

.copyright {
    text-align: center;
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-tertiary);
    font-size: 0.8rem;
}

/* Info Box */
.info-box {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 8px;
    margin-top: 1rem;
    margin-bottom: 3rem;
    border: 1px solid var(--border-color);
}

/* Responsive */
@media (max-width: 768px) {
    main {
        padding: 2rem 1.5rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero h1.hero-large {
        font-size: 2.25rem;
    }

    .hero {
        padding: 4rem 0;
    }

    .portfolio-card {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .feature-grid {
        grid-template-columns: 1fr;
    }
}