:root {
    --primary: #1e88e5;
    --secondary: #43a047;
    --bg: #f7fafd;
    --text: #222;
    --card-bg: #fff;
    --accent: #ffd600;
    --shadow: 0 4px 24px rgba(30,136,229,0.07);
    --radius: 16px;
    --transition: all 0.3s cubic-bezier(.4,0,.2,1);
}
[data-theme="dark"] {
    --primary: #90caf9;
    --secondary: #66bb6a;
    --bg: #181a1b;
    --text: #e0e0e0;
    --card-bg: #23272a;
    --accent: #ffd600;
    --shadow: 0 4px 24px rgba(30,136,229,0.12);
}

html, body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Inter', 'Poppins', Arial, sans-serif;
    margin: 0;
    padding: 0;
    min-height: 100vh;
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 3vw;
    height: 70px;
    background: var(--card-bg);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}
.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}
.logo-img {
    height: 38px;
    width: 38px;
}
.logo-text {
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary);
    letter-spacing: 1px;
}
.nav-links {
    display: flex;
    gap: 2vw;
    list-style: none;
}
.nav-links li a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    font-size: 1.08rem;
    padding: 8px 14px;
    border-radius: 6px;
    transition: var(--transition);
}
.nav-links li a.active, .nav-links li a:hover {
    background: var(--primary);
    color: #fff;
}
.theme-toggle {
    margin-left: 18px;
    background: var(--bg);
    border: none;
    border-radius: 50%;
    width: 38px;
    height: 38px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.3rem;
    cursor: pointer;
    transition: var(--transition);
}
.theme-toggle:hover {
    background: var(--primary);
    color: #fff;
}
.burger {
    display: none;
    flex-direction: column;
    gap: 5px;
    margin-left: 18px;
    cursor: pointer;
}
.burger span {
    display: block;
    width: 28px;
    height: 3px;
    background: var(--primary);
    border-radius: 2px;
    transition: var(--transition);
}

@media (max-width: 900px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100vw;
        background: var(--card-bg);
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow);
    }
    .nav-links.open {
        display: flex;
    }
    .burger {
        display: flex;
    }
}

.hero {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    padding: 60px 5vw 40px 5vw;
    min-height: 70vh;
    gap: 40px;
}
.hero-content {
    flex: 1 1 350px;
    min-width: 320px;
    z-index: 1;
}
.hero-content h1 {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 18px;
    line-height: 1.15;
}
.hero-content .highlight {
    color: var(--primary);
    font-size: 3.2rem;
    letter-spacing: 1px;
}
.hero-content .subtitle {
    font-size: 1.3rem;
    font-weight: 400;
    color: var(--secondary);
}
.hero-desc {
    font-size: 1.15rem;
    margin-bottom: 28px;
    color: var(--text);
}
.hero-badge {
    display: inline-block;
    background: var(--primary);
    color: #fff;
    font-size: 0.98rem;
    border-radius: 8px;
    padding: 4px 14px;
    margin-top: 10px;
    font-weight: 600;
    letter-spacing: 0.5px;
}
.hero-actions {
    display: flex;
    gap: 18px;
}
.btn {
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 1.08rem;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    box-shadow: 0 2px 8px rgba(30,136,229,0.08);
    letter-spacing: 0.5px;
}
.btn.primary {
    background: var(--primary);
    color: #fff;
}
.btn.secondary {
    background: var(--secondary);
    color: #fff;
}
.btn.primary:hover, .btn.secondary:hover {
    filter: brightness(1.1);
    transform: translateY(-2px) scale(1.04);
}
.hero-art {
    flex: 1 1 350px;
    min-width: 320px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.hero-art img {
    width: 100%;
    max-width: 420px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    background: var(--card-bg);
}

.contents-section {
    padding: 40px 5vw 20px 5vw;
    background: var(--card-bg);
    margin-bottom: 0;
}
.contents-section .section-title {
    margin-bottom: 18px;
}
.contents-list {
    list-style: none;
    padding: 0;
    margin: 0 auto;
    max-width: 600px;
    display: flex;
    flex-wrap: wrap;
    gap: 18px 32px;
    justify-content: center;
}
.contents-list li {
    margin: 0;
}
.contents-list a {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--bg);
    color: var(--primary);
    font-weight: 600;
    font-size: 1.08rem;
    padding: 10px 22px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(30,136,229,0.07);
    text-decoration: none;
    transition: var(--transition);
    border: 1.5px solid #e3eaf2;
}
.contents-list a:hover {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
    transform: translateY(-2px) scale(1.04);
}
.contents-list span {
    display: inline-block;
}

.project-overview .overview-grid {
    display: flex;
    gap: 32px;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 30px;
}
.overview-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 28px 24px;
    min-width: 260px;
    max-width: 420px;
    flex: 1 1 260px;
    border: 1.5px solid #e3eaf2;
}
.overview-card h3 {
    color: var(--primary);
    margin-bottom: 10px;
    font-size: 1.15rem;
}
.overview-card ul {
    margin: 0 0 0 18px;
    padding: 0;
    color: var(--text);
    font-size: 1.02rem;
}
.overview-card p {
    color: var(--text);
    font-size: 1.05rem;
}

.features-preview {
    padding: 40px 5vw 60px 5vw;
    background: var(--card-bg);
}
.section-title {
    text-align: center;
    font-size: 2.1rem;
    color: var(--primary);
    margin-bottom: 36px;
    font-weight: 700;
    letter-spacing: 0.5px;
}
.features-grid {
    display: flex;
    gap: 32px;
    justify-content: center;
    flex-wrap: wrap;
}
.feature-card {
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 32px 28px 28px 28px;
    max-width: 320px;
    min-width: 240px;
    flex: 1 1 240px;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: var(--transition);
    border: 1.5px solid #e3eaf2;
}
.feature-card:hover {
    transform: translateY(-6px) scale(1.03);
    border-color: var(--primary);
}
.feature-icon img {
    width: 54px;
    height: 54px;
    margin-bottom: 18px;
}
.feature-card h3 {
    font-size: 1.18rem;
    color: var(--primary);
    margin-bottom: 10px;
    font-weight: 600;
}
.feature-card p {
    font-size: 1.02rem;
    color: var(--text);
    text-align: center;
}

.hardware-section .hardware-grid {
    display: flex;
    gap: 28px;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 30px;
}
.hardware-card {
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px 18px 18px 18px;
    min-width: 180px;
    max-width: 220px;
    flex: 1 1 180px;
    display: flex;
    flex-direction: column;
    align-items: center;
    border: 1.5px solid #e3eaf2;
    transition: var(--transition);
}
.hardware-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px) scale(1.03);
}
.hardware-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 12px;
}
.hardware-card h3 {
    color: var(--primary);
    margin-bottom: 8px;
    font-size: 1.08rem;
}
.hardware-card p {
    color: var(--text);
    font-size: 0.98rem;
    text-align: center;
}

.software-section .software-grid {
    display: flex;
    gap: 28px;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 30px;
}
.software-card {
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 20px 18px;
    min-width: 220px;
    max-width: 320px;
    flex: 1 1 220px;
    display: flex;
    align-items: center;
    gap: 18px;
    border: 1.5px solid #e3eaf2;
    transition: var(--transition);
}
.software-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px) scale(1.03);
}
.software-icon {
    width: 44px;
    height: 44px;
}
.software-details h3 {
    color: var(--primary);
    margin-bottom: 6px;
    font-size: 1.08rem;
}
.software-purpose {
    color: var(--text);
    font-size: 0.98rem;
}

.workflow-section .workflow-diagram {
    display: flex;
    justify-content: center;
    margin-bottom: 24px;
}
.workflow-steps {
    max-width: 700px;
    margin: 0 auto;
    padding-left: 18px;
    color: var(--text);
    font-size: 1.05rem;
}
.workflow-steps li {
    margin-bottom: 10px;
}

.team-section .team-grid {
    display: flex;
    gap: 28px;
    flex-wrap: wrap;
    justify-content: center;
    margin-bottom: 30px;
}
.team-card {
    background: var(--bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 22px 16px 16px 16px;
    min-width: 160px;
    max-width: 200px;
    flex: 1 1 160px;
    display: flex;
    flex-direction: column;
    align-items: center;
    border: 1.5px solid #e3eaf2;
    transition: var(--transition);
}
.team-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px) scale(1.03);
}
.team-photo {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    margin-bottom: 10px;
    object-fit: cover;
    background: #e3eaf2;
}
.team-card h3 {
    color: var(--primary);
    margin-bottom: 6px;
    font-size: 1.08rem;
}
.team-card p {
    color: var(--text);
    font-size: 0.98rem;
    text-align: center;
}

.contact-section .contact-info {
    max-width: 400px;
    margin: 0 auto;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px 18px;
    color: var(--text);
    font-size: 1.08rem;
    border: 1.5px solid #e3eaf2;
    text-align: center;
}
.contact-section .contact-info p {
    margin-bottom: 10px;
}

.footer {
    background: var(--card-bg);
    border-top: 1.5px solid #e3eaf2;
    padding: 40px 0 20px 0;
    margin-top: 40px;
}
.footer-main {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding: 0 5vw;
}
.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary);
}
.footer-links {
    display: flex;
    gap: 24px;
}
.footer-links a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    font-size: 1.05rem;
    transition: color 0.2s;
}
.footer-links a:hover {
    color: var(--primary);
}
.footer-copy {
    color: #888;
    font-size: 0.98rem;
    margin-top: 10px;
}

@media (max-width: 1100px) {
    .features-grid,
    .hardware-grid,
    .software-grid,
    .team-grid {
        flex-wrap: wrap;
        gap: 18px;
    }
    .feature-card,
    .hardware-card,
    .software-card,
    .team-card {
        min-width: 180px;
        max-width: 100%;
        flex: 1 1 180px;
    }
}

@media (max-width: 900px) {
    .navbar {
        flex-wrap: wrap;
        padding: 0 2vw;
        height: auto;
    }
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100vw;
        background: var(--card-bg);
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow);
        z-index: 1000;
    }
    .nav-links.open {
        display: flex;
    }
    .burger {
        display: flex;
    }
    .hero,
    .footer-main {
        flex-direction: column;
        text-align: center;
        gap: 32px;
    }
    .hero-content {
        padding-right: 0;
        min-width: 0;
    }
    .hero-art {
        margin-top: 24px;
    }
    .features-grid,
    .hardware-grid,
    .software-grid,
    .team-grid {
        flex-direction: column;
        gap: 18px;
    }
    .feature-card,
    .hardware-card,
    .software-card,
    .team-card {
        max-width: 100%;
        min-width: 0;
    }
    .contents-list {
        flex-direction: column;
        gap: 10px;
    }
}

@media (max-width: 600px) {
    html, body {
        font-size: 15px;
    }
    .navbar {
        flex-direction: row;
        height: auto;
        padding: 0 1vw;
    }
    .logo-img {
        height: 32px;
        width: 32px;
    }
    .hero {
        padding: 32px 2vw 24px 2vw;
        min-height: 0;
        gap: 18px;
    }
    .hero-content h1 {
        font-size: 2rem;
    }
    .hero-content .highlight {
        font-size: 2.2rem;
    }
    .hero-content .subtitle {
        font-size: 1.1rem;
    }
    /* .hero-art img {
        max-width: 90vw;
        height: auto;
    } */
    .section-title {
        font-size: 1.3rem;
        margin-bottom: 18px;
    }
    .overview-card,
    .feature-card,
    .hardware-card,
    .software-card,
    .team-card {
        padding: 16px 8px;
    }
    .contents-section {
        padding: 24px 2vw 10px 2vw;
    }
    .footer-main {
        padding: 0 2vw;
        gap: 10px;
    }
    .footer-brand .logo-img {
        height: 28px;
        width: 28px;
    }
    .footer-links {
        gap: 8px;
    }
    .contact-info {
        padding: 14px 6px;
    }
}

/* SVG scaling for all icons and images */
.logo-img,
.feature-icon img,
.hardware-icon,
.software-icon,
.team-photo {
    width: 100%;
    max-width: 54px;
    height: auto;
    display: block;
    margin: 0 auto;
}

.hero-art img{
    width: 100%;
    max-width: 540px;
    height: auto;
    display: block;
    margin: 0 auto;
}

/* Fast transitions for nav and burger */
.nav-links,
.burger {
    transition: all 0.25s cubic-bezier(.4,0,.2,1);
}