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

:root {
    --color-green: rgb(9, 136, 227);
    --color-green-light: rgb(62, 162, 240);
    --color-green-dark: rgb(6, 108, 181);
    --color-green-subtle: rgba(9, 136, 227, 0.16);
    --color-green-border: rgba(9, 136, 227, 0.25);
    --color-green-glow: rgba(9, 136, 227, 0.15);
    --color-ink: #0a1410;
    --color-ink-mid: #3a5244;
    --color-ink-light: #7a9486;
    --color-paper: #f6f9f6;
    --color-white: #fff;
    --color-dark-bg: #0b1810;
    --color-dark-surface: #0f2218;
    --color-dark-border: hsla(0, 0%, 100%, 0.07);
    --color-dark-text: hsla(0, 0%, 100%, 0.88);
    --color-dark-text-mid: hsla(0, 0%, 100%, 0.48);
    --font-sans: "IBM Plex Sans", system-ui, -apple-system, sans-serif;
    --font-mono: "IBM Plex Mono", "Fira Code", monospace;
    --fw-regular: 400;
    --fw-medium: 500;
    --fw-semibold: 600;
    --fw-bold: 700;
    --ls-tight: -0.04em;
    --ls-snug: -0.02em;
    --ls-normal: 0em;
    --ls-wide: 0.08em;
    --ls-wider: 0.1em;
    --radius-sm: 5px;
    --radius-md: 7px;
    --radius-lg: 10px;
    --radius-xl: 12px;
    --radius-2xl: 16px;
    --radius-pill: 9999px;
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;
    --shadow-sm: 0 1px 3px rgba(10, 20, 14, 0.06), 0 1px 2px rgba(10, 20, 14, 0.04);
    --shadow-md: 0 4px 12px rgba(10, 20, 14, 0.08), 0 2px 4px rgba(10, 20, 14, 0.04);
    --shadow-lg: 0 12px 32px rgba(10, 20, 14, 0.1), 0 4px 8px rgba(10, 20, 14, 0.04);
    --transition-fast: 0.12s ease;
    --transition-base: 0.18s ease;
    --transition-slow: 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--color-paper);
    color: var(--color-ink);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

@media (min-width: 640px) {
    .container {
        padding: 0 2rem;
    }
}

.navbar {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(246, 249, 246, 0.85);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--color-green-border);
    box-shadow: var(--shadow-sm);
}

.navbar-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    text-decoration: none;
    user-select: none;
}

.logo-area img {
    width: 50px;
    height: 50px;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: var(--fw-bold);
    color: var(--color-green-dark);
    letter-spacing: var(--ls-snug);
}

.nav-links {
    display: none;
    align-items: center;
    gap: 2rem;
    font-size: 0.9rem;
    font-weight: var(--fw-medium);
    color: var(--color-ink-mid);
}

.nav-links a {
    color: var(--color-ink-mid);
    transition: color var(--transition-fast);
}

.nav-links a:hover {
    color: var(--color-green);
}

.menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    padding: 0;
    color: var(--color-ink-light);
    background: none;
    border: none;
    cursor: pointer;
    transition: color var(--transition-fast);
}

.menu-btn:hover,
.menu-btn:focus-visible {
    color: var(--color-green);
}

.menu-icon {
    position: relative;
    display: block;
    width: 22px;
    height: 16px;
}

.bar {
    position: absolute;
    left: 0;
    width: 100%;
    height: 2px;
    background: currentColor;
    border-radius: 999px;
    transition: transform var(--transition-base), opacity var(--transition-base), top var(--transition-base);
}

.bar-1 {
    top: 0;
}

.bar-2 {
    top: 7px;
}

.bar-3 {
    top: 14px;
}

.menu-btn.active .bar-1 {
    top: 7px;
    transform: rotate(45deg);
}

.menu-btn.active .bar-2 {
    opacity: 0;
}

.menu-btn.active .bar-3 {
    top: 7px;
    transform: rotate(-45deg);
}

.mobile-menu {
    display: block;
    padding-bottom: var(--space-4);
    font-size: 0.9rem;
    font-weight: var(--fw-medium);
    color: var(--color-ink-mid);
}

.mobile-menu.hidden {
    display: none;
}

.mobile-menu a {
    display: block;
    padding: var(--space-3) 0;
    color: var(--color-ink-mid);
}

.mobile-menu a:hover {
    color: var(--color-green);
}

@media (min-width: 768px) {
    .nav-links {
        display: flex;
    }

    .menu-btn {
        display: none;
    }

    .mobile-menu {
        display: none !important;
    }
}

.hero {
    background: var(--color-dark-bg);
    color: var(--color-dark-text);
    padding: 5rem 0;
    text-align: center;
}

@media (min-width: 768px) {
    .hero {
        padding: 7rem 0;
    }
}

.hero p {
    font-size: 1.05rem;
    color: var(--color-dark-text-mid);
    max-width: 40rem;
    margin: 1rem auto 0;
}

.hero-buttons {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-4);
    margin-top: 2rem;
}

.btn-primary {
    background: var(--color-green);
    color: white;
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-md);
    font-weight: var(--fw-semibold);
    transition: background var(--transition-fast), box-shadow var(--transition-fast);
    box-shadow: 0 4px 12px rgba(87, 169, 111, 0.3);
}

.btn-primary:hover {
    background: var(--color-green-dark);
    box-shadow: 0 8px 20px rgba(87, 169, 111, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--color-dark-text);
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-md);
    font-weight: var(--fw-semibold);
    transition: background var(--transition-fast);
    border: 1px solid var(--color-dark-border);
    backdrop-filter: blur(4px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: var(--fw-bold);
    color: var(--color-ink);
    letter-spacing: var(--ls-snug);
}

.section-title p {
    color: var(--color-ink-light);
    margin-top: var(--space-3);
    font-size: 1rem;
}

.features-section {
    padding: var(--space-20) 0;
    background: var(--color-white);
}

.features-grid {
    display: grid;
    gap: var(--space-6);
}

@media (min-width: 768px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.feature-card {
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-green-border);
    background: var(--color-white);
    transition: box-shadow var(--transition-base), transform var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.feature-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.feature-icon {
    width: 2.75rem;
    height: 2.75rem;
    background: var(--color-green-subtle);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    transition: background var(--transition-fast);
}

.feature-card:hover .feature-icon {
    background: var(--color-green-glow);
}

.feature-card h3 {
    font-size: 1.1rem;
    font-weight: var(--fw-semibold);
    margin-top: var(--space-4);
    color: var(--color-ink);
}

.feature-card p {
    color: var(--color-ink-light);
    font-size: 0.95rem;
    margin-top: var(--space-2);
    line-height: 1.5;
}

.demo-section {
    padding: var(--space-20) 0;
    background: var(--color-paper);
}

.demo-grid {
    display: grid;
    gap: var(--space-6);
}

@media (min-width: 768px) {
    .demo-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.demo-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    text-align: center;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-green-border);
    transition: box-shadow var(--transition-base);
}

.demo-card:hover {
    box-shadow: var(--shadow-md);
}

.demo-card .tz-label {
    font-size: 0.85rem;
    font-weight: var(--fw-semibold);
    color: var(--color-green);
    letter-spacing: var(--ls-snug);
}

.demo-card .time-display {
    font-size: clamp(1.75rem, 4vw, 1.5rem);
    font-weight: var(--fw-bold);
    color: var(--color-ink);
    margin-top: var(--space-3);
    letter-spacing: 0.02em;
    font-family: var(--font-mono);
}

.demo-card .date-display {
    font-size: 0.9rem;
    color: var(--color-ink-light);
    margin-top: var(--space-2);
}

.stats-section {
    padding: var(--space-16) 0;
    background: var(--color-white);
    border-top: 1px solid var(--color-green-border);
    border-bottom: 1px solid var(--color-green-border);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
    text-align: center;
}

@media (min-width: 768px) {
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.stat-number {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    font-weight: var(--fw-bold);
    color: var(--color-green);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--color-ink-light);
    margin-top: var(--space-2);
}

.footer {
    background: var(--color-dark-bg);
    color: var(--color-dark-text-mid);
    padding: var(--space-6) 0;
}

.footer-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-4);
    text-align: center;
}

.footer-links {
    display: flex;
    gap: var(--space-6);
}

.footer-links a {
    color: var(--color-dark-text-mid);
    transition: color var(--transition-fast);
    font-weight: var(--fw-medium);
}

.footer-links a:hover {
    color: var(--color-green-light);
}

@media (min-width: 768px) {
    .footer-inner {
        flex-direction: row;
        justify-content: space-between;
        text-align: left;
    }
}