:root {
    /* Primary Colors */
    --intro-email-bg: hsl(217, 28%, 15%);
    --main-bg: hsl(218, 28%, 13%);
    --footer-bg: hsl(216, 53%, 9%);
    --testimonials-bg: hsl(219, 30%, 18%);
    
    /* Accent Colors */
    --cyan: hsl(176, 68%, 64%);
    --blue: hsl(198, 60%, 50%);
    --light-red: hsl(0, 100%, 63%);
    
    /* Neutral */
    --white: hsl(0, 0%, 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    font-size: 62.5%; /* 1rem = 10px*/
}

body {
    font-family: 'Open Sans', sans-serif;
    background-color: var(--main-bg);
    color: var(--white);
    line-height: 1.6;
}

h1, h2, h3, h4, button {
    font-family: 'Raleway', sans-serif;
}


/* header styling */
header {
    padding: 3.2rem 5%;
    background-color: var(--intro-email-bg);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1440px;
    margin: 0 auto;
}

.logo {
    width: 17.6rem; /* 176px */
}

nav ul {
    display: flex;
    justify-content: space-between;
    list-style: none;
    gap: 4.8rem; /* 48px */
}

nav a {
    color: var(--white);
    opacity: 0.7;
    text-decoration: none;
    font-family: 'Raleway', sans-serif;
    font-size: 1.6rem;
    transition: all 0.3s ease;
}

nav a:hover {
    text-decoration: underline;
    opacity: 1.2;
}

/* Hero section */

.hero {
    text-align: center;
    background-color: var(--intro-email-bg);
    width: 100%;
    padding: 3.2rem 0% 19.2rem;
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 449px;
    background-image: url('images/bg-curvy-desktop.svg');
    background-size: 100% 100%;
    background-position: bottom center;
    background-repeat: no-repeat;
    z-index: 1;
}

.hero-image {
    max-width: 720px;
    width: 100%;
    margin-bottom: 2rem;
    position: relative;
    z-index: 2;
}

.hero h1 {
    font-size: 4rem;
    margin-bottom: 1.6rem;
    margin: 0 auto 2.4rem;
    max-width: 720px;
    position: relative;
    z-index: 2;
    color: var(--white);
}

.hero p {
    max-width: 600px;
    margin: 0 auto 3.2rem;
    position: relative;
    z-index: 2;
    font-size: 1.6rem;
}

.cta-button {
    color: var(--white);
    background: linear-gradient(to right, var(--cyan), var(--blue));;
    font-size: 1.6rem;
    padding: 1.5rem 8rem;
    border-radius: 50px;
    border: none;
    position: relative;
    z-index: 2;
    cursor: pointer;
    font-weight: 700;
    transition: transform 0.3s ease;
}

.cta-button:hover {
    transform: translate(0, -5px);
}

/* Feature section */
.features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8rem;
    max-width: 880px;
    margin: 0 auto;
    padding: 8rem 3.2rem;
    font-size: 1.6rem;
    text-align: center;
}

.feature-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2.4rem;
}

.feature-card img{
    width: 80px;
    height: 80px;
    margin-bottom: 1.6rem
}

.feature-card h3 {
    font-size: 2rem;
    margin-bottom: 0.8rem;
    color: var(--white);
}

/* Productive section */
.productive {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 6.4rem;
    max-width: 1200px;
    align-items: center;
    margin: 0 auto;
    padding: 8rem 3.2rem;
}

.productive-img {
    width: 100%;
}

.productive-content {
    margin-right: 3.2rem;
}

.productive h2 {
    font-size: 4rem;
    margin-bottom: 2.4rem;
}

.productive p {
    margin-bottom: 1.6rem;
    font-size: 1.6rem;
}

.see-how {
    color: var(--cyan);
    text-decoration: underline var(--cyan);
    font-size: 1.6rem;
    padding: 0.4rem;
}

    
.see-how:hover {
    opacity: 0.5;
}

/* Testimonial section */
.testimonials {
    max-width: 1200px;
    margin: 0 auto;
    padding: 8rem 3.2rem;
    position: relative;
}

.quotes {
    position: absolute;
    top: 6.4rem;
    left: 1.6rem;
    z-index: 0;
}

.testimonial-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3.2rem;
    position: relative;
    z-index: 1;
}

.testimonial-card {
    background-color: var(--testimonials-bg);
    padding: 3.2rem;
    border-radius: 5px;
}

.testimonial-card > p {
    font-size: 1.6rem;
    color: var(--white);
}

.profile {
    display: flex;
    align-items: center;
    gap: 1.6rem;
    margin-top: 2.4rem;
}

.profile img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
}

.profile h4 {
    font-size: 1.44rem;
    margin-bottom: 0.4rem;
}

.profile p {
    font-size: 1.28rem;
    opacity: 0.8;
}

/* Early Access Section */
.early-access {
    background-color: var(--intro-email-bg);
    text-align: center;
    max-width: 864px;
    margin: 0 auto;
    padding: 4.8rem;
    border-radius: 10px;
    position: relative;
    top: 150px;
    z-index: 1;
    box-shadow: 5px 5px 15px rgba(0, 0, 0, 0.2);
}

.early-access h2 {
    margin-bottom: 2.4rem;
    font-size: 2.4rem;
}

.early-access p {
    margin-bottom: 3.2rem;
    max-width: 620px;
    margin-left: auto;
    margin-right: auto ;
    font-size: 1.6rem;
}

form {
    display: flex;
    gap: 3.2rem;
    max-width: 800px;
    margin: 0 auto;
}

form input {
    flex: 1;
    padding: 1.6rem 3.2rem;
    border-radius: 50px;
    border: none;
    outline: none;
}

form button {
    background: linear-gradient(to right, var(--cyan), var(--blue));
    color: var(--white);
    border: none;
    border-radius: 50px;
    padding: 1.6rem 3.2rem;
    cursor: pointer;
    transition: transform 0.3s;
    font-weight: 700;
}

form button:hover {
    transform: translate(0, -5px);
}

/* Footer */
footer {
    background-color: var(--footer-bg);
    padding: 19.2rem 5% 8rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 6.4rem;
    padding-top: 4.8rem;
}

.footer-logo {
    margin-bottom: 3.2rem;
}

.location {
    display: flex;
    gap: 2.4rem ;
    align-items: flex-start;
    font-size: 1.6rem;
}

.location img {
    margin-top: 0.8rem;
}

.contact > div {
    display: flex;
    gap: 2.4rem;
    margin-bottom: 1.6rem;
    font-size: 1.6rem;
}

.footer-links ul {
    list-style: none;
    font-size: 1.6rem;
}

.footer-links a {
    color: var(--white);
    text-decoration: none;
    line-height: 2;
    transition: color 0.3s;
}

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

.social-links {
    display: flex;
    gap: 1rem;
}

.social-icon {
    color: var(--white);
    border: 1px solid var(--white);
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all 0.3s;
}

.social-icon:hover {
    color: var(--cyan);
    border-color: var(--cyan);
    transform: translateY(-2px);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .features {
        gap: 4.8rem;
    }

    .testimonial-cards {
        gap: 2.4rem;
    }

    .footer-content {
        grid-template-columns: 1.5fr 1fr 1fr 1fr;
        gap: 3.2rem;
    }
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .features {
        grid-template-columns: 1fr;
        max-width: 500px;
    }
    
    .productive {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .productive-content {
        padding-right: 0px;
        margin-right: 0px;
    }
    
    .testimonial-cards {
        grid-template-columns: 1fr;
    }
    
    .early-access {
        padding: 2rem;
        margin: 0 1rem;
    }
    
    .early-access form {
        flex-direction: column;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .social-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 50%;
    }

    .logo {
        width: 30%;
    }

    .footer-logo {
        margin-top: 8rem;
    }

    nav {
        gap: 2rem;
    }
    
    nav ul {
        gap: 1.5rem;
    }
    
    .hero::after {
        background-image: url('images/bg-curvy-mobile.svg');
        height: 150px;
        bottom: -1px;
    }
    
    .hero {
        padding: 0 8% 12rem;
    }

    .hero h1 {
        font-size: 3.1rem;
    }
    
    .cta-button {
        padding: 1.5rem 8rem;
    }

    .features {
        margin-top: 10rem;
    }
}