:root {
    --main: #00796B;
    --primary-font-family: "Crimson Pro";
    --secondary-font-family: "Nunito Sans";
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    outline: none;
}

body {
    background: var(--main);
}

.container {
    line-height: 1.6;
    color: white;
    z-index: 1;
}

h1 {
    font-family: var(--primary-font-family), sans-serif;
}

/* Navigation Styles */
.navbar {
    background: var(--main);
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 0 auto;
    padding: 20px 75px;
    z-index: 10;
    position: fixed;
    width: 100%;
    top: 0;
}

.logo {
    font-size: 2rem;
    font-weight: 500;
    font-family: var(--primary-font-family), sans-serif;
}

.logo a {
    text-decoration: none;
    color: white;
}

.nav-links {
    display: flex;
    font-family: var(--secondary-font-family), serif;
    gap: 30px;
    font-size: 1.2rem;
    align-items: center;
}

.nav-links a {
    color: rgba(255,255,255,0.95);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: rgba(255, 255, 255, 0.8);
}

.nav-links .learn-words-btn {
    color: var(--main);
    transition: color 0.3s ease;
}
.nav-links .learn-words-btn:hover {
    color: var(--main);
}

.learn-words-btn {
    background: white;
    font-family: var(--secondary-font-family), serif;
    padding: 10px 20px 10px;
    border-radius: 12px;
    color: var(--main);
    font-size: 1.2rem;
    font-weight: 600;
    border: none;
    transition-duration: 0.2s;
    text-decoration: none;
    display: flex;
    max-width: fit-content;
    gap: 7px;
}

.learn-words-btn:hover {
    background: #f6f6f6;
    color: var(--main);
    cursor: pointer;
}

/* Hero Section */
.hero-section {
    background: var(--main);
    min-height: 100vh;
    padding: 10px 20px;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--main);
}

.hero-content {
    max-width: 1200px;
    margin: 30px auto 0;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    align-items: center;
    padding: 90px 0 20px 0;
    position: relative;
    z-index: 1;
}

.hero-text h1 {
    font-size: 4rem;
    font-weight: bold;
    line-height: 4.6rem;
    margin-bottom: 10px;
}

.hero-text p {
    font-size: 2.4rem;
    font-family: var(--primary-font-family), sans-serif;
    margin-bottom: 80px;
}

.phone-mockup {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 25px;
    padding: 10px;
    max-width: 320px;
    margin: 0 auto;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.phone-mockup video {
    border-radius: 15px;
}

/* How It Works Section */
.how-it-works {
    background: var(--main);
    padding: 0 20px;
    text-align: center;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    font-family: var(--secondary-font-family), serif;
}

.how-it-works-title {
    font-size: 4rem;
    font-family: var(--primary-font-family), sans-serif;
    font-weight: bold;
}

.how-it-works-subtitle {
    font-size: 2rem;
    opacity: 0.9;
    margin-bottom: 80px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 60px;
    margin-bottom: 100px;
}

.feature {
    text-align: center;
}

.feature-icon {
    width: 100px;
    height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 30px;
    font-size: 6rem;
    backdrop-filter: blur(10px);
}

.feature h3 {
    font-size: 2rem;
    font-weight: bold;
    margin-bottom: 10px;
}

.feature p {
    opacity: 0.9;
    font-weight: 300;
    font-size: 1.4rem;
}

/* Science Section */
.science-section {
    text-align: left;
    width: 100%;
    padding: 0 20px;
}

.science-title {
    font-size: 4rem;
    font-weight: bold;
    font-family: var(--primary-font-family), sans-serif;
}

.science-text {
    font-weight: 300;
    font-size: 1.4rem;
    opacity: 0.9;
    max-width: 800px;
}

.science-text a {
    color: white;
    transition-duration: 0.2s;
}

.forgetting-curve {
    padding: 20px 0;
    backdrop-filter: blur(10px);
    position: relative;
}

.chart-explanation {
    text-align: right;
    font-weight: 300;
    font-size: 1.4rem;
    opacity: 0.9;
    position: absolute;
    max-width: 600px;
    right: 0;
}

/* Policy Page Styles */
.policy {
    padding-top: 150px;
}

.policy h1 {
    font-size: 3rem;
}

.policy a {
    color: white;
}

.policy h2 {
    font-size: 1.9rem;
    padding-top: 30px;
}

.policy p, .policy ul {
    font-size: 1.25rem;
    font-weight: 300;
}

.policy ul {
    padding-left: 30px;
    padding-bottom: 20px;
    padding-top: 10px;
}

/* Footer */
.footer {
    font-family: var(--secondary-font-family), serif;
    background: #000;
    margin-top: 200px;
    padding: 40px 20px 40px;
    text-align: center;
}

.footer-cta {
    font-size: 2.3rem;
    font-weight: bold;
    margin-bottom: 30px;
    font-family: var(--primary-font-family), sans-serif;
}

.footer .container {
    display: flex;
    justify-content: center;
    flex-direction: column;
}

.footer .container div {
    width: 100%;
    text-align: center;
    display: flex;
    justify-content: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 60px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.footer-links a {
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 300;
    line-height: 3rem;
    color: rgba(255, 255, 255, 0.78);
}

.footer-links span {
    font-size: 1.8rem;
}

.footer-links a:hover {
    color: white;
}

.copyright {
    font-size: .8rem;
    opacity: 0.5;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .navbar {
        text-align: center;
        display: flex;
        justify-content: center;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }

    .hero-text {
        display: flex;
        flex-direction: column;
    }

    .hero-text div {
        display: flex;
        justify-content: center;
    }

    .hero-text h1 {
        font-size: 2.5rem;
        line-height: 3.2rem;
    }

    .hero-text p {
        font-size: 2rem;
    }

    .phone-mockup {
        box-shadow: none;
    }

    .how-it-works-title {
        font-size: 3rem;
        line-height: 2rem;
        padding-top: 40px;
    }

    .how-it-works-subtitle {
        font-size: 1.5rem;
        line-height: 2rem;
        padding-top: 20px;
        font-weight: 300;
    }

    .features-grid {
        gap: 40px;
    }

    .nav-links {
        gap: 15px;
    }

    .nav-links a {
        display: none;
    }

    .science-title {
        line-height: 4rem;
        padding-bottom: 20px;
    }

    .forgetting-curve {
        display: none;
    }

    .chart-explanation {
        padding: 20px;
        text-align: left;
    }

    .footer-links {
        gap: 5px;
        flex-direction: column;
    }

    .footer-links span {
        display: none;
    }

    /* Policy page mobile styles */
    .policy {
        padding-left: 20px;
        padding-right: 20px;
    }

    .policy h1 {
        font-size: 2.5rem;
        line-height: 3rem;
    }
}