/* Author: Shuyu Fan, MSc */
/* Date: December 8, 2025 */

/* ===== CSS Reset & Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette - inspired by mountain landscapes */
    --primary-black: #1a1a1a;
    --secondary-grey: #333333;
    --light-grey: #f5f5f5;
    --white: #ffffff;
    --accent-purple: #7b68ee;
    --accent-orange: #ff6b35;
    --text-grey: #666666;

    /* Typography */
    --font-main: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-heading: 'Georgia', serif;

    /* Spacing */
    --section-padding: 80px 20px;
    --container-max-width: 1200px;
}

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 20px 0;
    transition: all 0.3s ease;
}

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

.logo {
    font-size: 24px;
    font-weight: bold;
    color: var(--white);
    letter-spacing: 1px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    color: var(--white);
    text-decoration: none;
    font-size: 16px;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-purple);
    transition: width 0.3s ease;
}

.nav-links a:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--white);
    transition: all 0.3s ease;
}

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-black) 0%, var(--secondary-grey) 100%);
    color: var(--white);
    text-align: center;
    padding-top: 80px;
}

.hero-content h1 {
    font-family: var(--font-heading);
    font-size: 64px;
    font-weight: bold;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.tagline {
    font-size: 28px;
    margin-bottom: 10px;
    color: var(--accent-purple);
    font-weight: 300;
}

.subtitle {
    font-size: 20px;
    margin-bottom: 40px;
    color: rgba(255, 255, 255, 0.8);
}

.cta-button {
    display: inline-block;
    padding: 15px 40px;
    background-color: var(--accent-orange);
    color: var(--white);
    text-decoration: none;
    border-radius: 50px;
    font-size: 18px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(255, 107, 53, 0.3);
}

.cta-button:hover {
    background-color: #ff8555;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 53, 0.4);
}

/* ===== Section Styles ===== */
section {
    padding: var(--section-padding);
}

section h2 {
    font-family: var(--font-heading);
    font-size: 42px;
    margin-bottom: 30px;
    text-align: center;
    color: var(--primary-black);
}

section .content {
    max-width: 800px;
    margin: 0 auto;
    font-size: 18px;
    line-height: 1.8;
    color: var(--text-grey);
}

section .content p {
    margin-bottom: 20px;
}

/* ===== About Section ===== */
.about {
    background-color: var(--white);
}

/* ===== Mission Section ===== */
.mission {
    background-color: var(--light-grey);
}

.mission-content {
    text-align: center;
    padding: 40px 20px;
}

.mission-statement {
    font-family: var(--font-heading);
    font-size: 36px;
    font-style: italic;
    color: var(--secondary-grey);
    max-width: 600px;
    margin: 0 auto 20px auto;
}

.mission-description {
    font-size: 18px;
    color: var(--text-grey);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ===== Team Section ===== */
.team {
    background-color: var(--white);
}

/* ===== Apps Section ===== */
.apps {
    background-color: var(--light-grey);
}

.apps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.app-card {
    background-color: var(--white);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.app-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.15);
}

.app-card h3 {
    font-family: var(--font-heading);
    font-size: 24px;
    color: var(--primary-black);
    margin-bottom: 15px;
}

.app-card p {
    color: var(--text-grey);
    margin-bottom: 20px;
    line-height: 1.6;
}

.app-link {
    display: inline-block;
    color: var(--accent-purple);
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
}

.app-link:hover {
    color: var(--accent-orange);
    transform: translateX(5px);
}

/* ===== Contact Section ===== */
.contact {
    background: linear-gradient(135deg, var(--secondary-grey) 0%, var(--primary-black) 100%);
    color: var(--white);
}

.contact h2 {
    color: var(--white);
}

.contact-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-content p {
    font-size: 20px;
    margin-bottom: 30px;
    color: rgba(255, 255, 255, 0.9);
}

.email-link {
    display: inline-block;
    font-size: 24px;
    color: var(--accent-purple);
    text-decoration: none;
    padding: 10px 20px;
    border: 2px solid var(--accent-purple);
    border-radius: 10px;
    transition: all 0.3s ease;
}

.email-link:hover {
    background-color: var(--accent-purple);
    color: var(--white);
    transform: scale(1.05);
}

/* ===== Footer ===== */
.footer {
    background-color: var(--primary-black);
    color: var(--white);
    text-align: center;
    padding: 30px 20px;
}

.footer p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.7);
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: rgba(26, 26, 26, 0.98);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease;
        padding: 20px 0;
        gap: 0;
    }

    .nav-links li {
        padding: 15px 0;
    }

    .nav-links.active {
        left: 0;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }

    .hero-content h1 {
        font-size: 42px;
    }

    .tagline {
        font-size: 22px;
    }

    .subtitle {
        font-size: 18px;
    }

    section h2 {
        font-size: 32px;
    }

    .mission-statement {
        font-size: 28px;
    }

    section .content {
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 32px;
    }

    .tagline {
        font-size: 18px;
    }

    .subtitle {
        font-size: 16px;
    }

    section h2 {
        font-size: 28px;
    }

    .cta-button {
        padding: 12px 30px;
        font-size: 16px;
    }
}