/* Variables */
:root {
    --primary-dark: #0A192F;
    --primary-light: #172A45;
    --accent-blue: #00B4D8;
    --accent-coral: #FF6B6B;
    --text-white: #E6F1FF;
    --text-gray: #8892B0;
    --font-main: 'Inter', sans-serif;
}

/* Global Reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    background-color: var(--primary-dark);
    color: var(--text-white);
    line-height: 1.6;
}

/* Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.text-highlight {
    color: var(--accent-blue);
}

.btn-primary {
    background-color: transparent;
    border: 1px solid var(--accent-blue);
    color: var(--accent-blue);
    padding: 12px 24px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: rgba(0, 180, 216, 0.1);
}

.btn-secondary {
    color: var(--text-white);
    padding: 12px 24px;
    text-decoration: none;
    margin-left: 20px;
    font-weight: 600;
}

/* Navbar */
.navbar {
    padding: 20px 0;
    position: sticky;
    top: 0;
    background-color: rgba(10, 25, 47, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
}

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    color: var(--text-white);
    text-decoration: none;
    font-size: 0.9rem;
}

/* Hero Section */
.hero {
    padding: 100px 0;
    min-height: 90vh;
    display: flex;
    align-items: center;
    background: radial-gradient(circle at 70% 50%, rgba(0, 180, 216, 0.1) 0%, transparent 50%);
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.1;
}

.hero-sub {
    font-size: 1.2rem;
    color: var(--text-gray);
    max-width: 600px;
    margin-bottom: 40px;
}

/* Problem Section */
.section-dark {
    background-color: var(--primary-dark);
    padding: 100px 0;
}

.grid-2-col {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.feature-list {
    list-style: none;
    margin-top: 30px;
}

.feature-list li {
    margin-bottom: 15px;
    color: var(--text-gray);
}

.feature-list i {
    color: var(--accent-coral);
    margin-right: 10px;
    width: 20px;
}

.card-alert {
    background-color: var(--primary-light);
    padding: 30px;
    border-radius: 10px;
    border-left: 4px solid var(--accent-coral);
}

.graph-mockup {
    height: 200px;
    position: relative;
    border-bottom: 1px solid var(--text-gray);
    border-left: 1px solid var(--text-gray);
    margin-bottom: 20px;
    display: flex;
    align-items: flex-end;
}

/* Abstract graph lines using CSS borders */
.graph-line {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.oxygen {
    border-bottom: 2px solid var(--accent-coral);
    transform: skewY(10deg);
    transform-origin: bottom left;
    opacity: 0.8;
}

.symptoms {
    border-bottom: 2px dashed var(--text-gray);
    width: 100%;
    bottom: 80%;
    position: absolute;
}

.graph-label {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--accent-coral);
    font-weight: bold;
    text-transform: uppercase;
    font-size: 0.8rem;
    letter-spacing: 2px;
}

.caption {
    font-size: 0.9rem;
    color: var(--text-gray);
}

/* Solution Section */
.section-light {
    background-color: #0d203a;
    padding: 100px 0;
}

.grid-3-col {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.card {
    background-color: var(--primary-light);
    padding: 30px;
    border-radius: 8px;
    transition: transform 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
}

.card-icon {
    font-size: 2rem;
    color: var(--accent-blue);
    margin-bottom: 20px;
}

.card h3 {
    margin-bottom: 15px;
    color: var(--text-white);
}

.card p {
    color: var(--text-gray);
    font-size: 0.95rem;
}

/* Technology Section */
.section-tech {
    padding: 100px 0;
    text-align: center;
    border-top: 1px solid var(--primary-light);
}

.partner-logos {
    display: flex;
    justify-content: center;
    gap: 50px;
    margin-top: 40px;
    flex-wrap: wrap;
}

.partner {
    font-weight: 800;
    color: var(--text-gray);
    font-size: 1.2rem;
    letter-spacing: 1px;
}

/* Footer */
footer {
    padding: 80px 0 40px;
    text-align: center;
    background-color: #050d1a;
}

.footer-cta h2 {
    margin-bottom: 20px;
}

.footer-cta p {
    margin-bottom: 40px;
    color: var(--text-gray);
}

.footer-bottom {
    margin-top: 80px;
    color: var(--text-gray);
    font-size: 0.8rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--primary-light);
    padding-top: 20px;
}

.socials a {
    color: var(--text-gray);
    margin-left: 20px;
    font-size: 1.2rem;
    transition: color 0.3s;
}

.socials a:hover {
    color: var(--accent-blue);
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .navbar .container {
        flex-direction: column;
    }
    
    .nav-links {
        margin-top: 20px;
        flex-direction: column;
        gap: 15px;
    }
    
    .nav-links li {
        margin: 0;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

    .grid-2-col, .grid-3-col {
        grid-template-columns: 1fr;
    }
    
    .hero-btns {
        display: flex;
        flex-direction: column;
        gap: 15px;
    }
    
    .btn-secondary {
        margin-left: 0;
        text-align: center;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 20px;
    }
}