/* Modern Reset & Variables */
:root {
    --primary: #2d6a4f;
    --primary-dark: #1b4332;
    --secondary: #d8f3dc;
    --accent: #b7e4c7;
    --text-main: #1f2937;
    --text-light: #6b7280;
    --bg-body: #f9fafb;
    --bg-card: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(255, 255, 255, 0.3);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;
    --transition: all 0.3s ease;
}

/* for tutorial show-button */
.hidden {
    display: none;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    background-image: 
        radial-gradient(at 0% 0%, hsla(152,100%,93%,1) 0, transparent 50%), 
        radial-gradient(at 100% 0%, hsla(135,100%,96%,1) 0, transparent 50%);
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--primary-dark);
}

a {
    text-decoration: none;
    color: forestgreen;
    transition: var(--transition);
}

a:hover {
    text-decoration: none;
    color: limegreen;
}

img {
    max-width: 100%;
    display: block;
    border-radius: 12px;
}

.header-image{
    max-width: 200px;
    max-height: 200px;
}

/* Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.desc-list{
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    gap: 1.25rem;
    padding-bottom: 1rem;
}

.section {
    padding: 3rem 0;
}

.text-center { text-align: center; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 2rem; }
.mb-8 { margin-bottom: 4rem; }

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--glass-border);
    padding: 1rem 0;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary);
    font-family: var(--font-heading);
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-link {
    font-weight: 500;
    color: var(--text-main);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background-color: var(--primary);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Hero Section */
.hero {
    padding: 10rem 0 2rem;
    text-align: center;
    background: linear-gradient(180deg, rgba(216, 243, 220, 0.3) 0%, rgba(255,255,255,0) 100%);
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, var(--primary-dark), var(--primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: fadeInUp 0.8s ease-out;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto 2.5rem;
    animation: fadeInUp 0.8s ease-out 0.2s backwards;
}

.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(45, 106, 79, 0.39);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(45, 106, 79, 0.23);
}

/* Cards & Glassmorphism */
.card {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

/* About Page Specifics */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(125px, 1fr));
    gap: 2rem;
}

.feature-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

/* Team Page Specifics */
.team-member {
    display: flex;
    align-items: center;
    gap: 4rem;
    margin-bottom: 6rem;
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.8s ease-out forwards;
}

.team-member:nth-child(even) {
    flex-direction: row-reverse;
}

.team-img-wrapper {
    flex: 1;
    position: relative;
}

.team-img-wrapper img {
    width: 100%;
    height: 400px;
    object-fit: cover;
    box-shadow: var(--shadow-lg);
}

.team-info {
    flex: 1;
}

.team-info h3 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.team-role {
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 1.5rem;
    display: block;
}

/* Download Page Specifics */
.download-options {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.download-card {
    text-align: center;
    padding: 3rem 2rem;
    max-width: 350px;
}

.download-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    color: var(--primary);
}

/* Tutorial Page Specifics */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--secondary);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
    border-radius: 2px;
}

.step {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
    box-sizing: border-box;
}

.step::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: var(--bg-body);
    border: 4px solid var(--primary);
    top: 25px;
    border-radius: 50%;
    z-index: 1;
}

.left { left: 0; }
.right { left: 50%; }

.left::before {
    content: " ";
    height: 0;
    position: absolute;
    top: 22px;
    width: 0;
    z-index: 1;
    right: 30px;
    border: medium solid white;
    border-width: 10px 0 10px 10px;
    border-color: transparent transparent transparent white;
}

.right::before {
    content: " ";
    height: 0;
    position: absolute;
    top: 22px;
    width: 0;
    z-index: 1;
    left: 30px;
    border: medium solid white;
    border-width: 10px 10px 10px 0;
    border-color: transparent white transparent transparent;
}

.right::after { left: -10px; }

.step-content {
    padding: 20px 30px;
    background-color: white;
    position: relative;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
}

/* Footer */
footer {
    background-color: white;
    padding: 3rem 0;
    margin-top: 4rem;
    border-top: 1px solid var(--glass-border);
    text-align: center;
    color: var(--text-light);
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media screen and (max-width: 768px) {
    .feature-grid { grid-template-columns: 1fr; gap: 2rem; }
    .team-member { flex-direction: column !important; gap: 2rem; }
    .timeline::after { left: 31px; }
    .step { width: 100%; padding-left: 70px; padding-right: 25px; }
    .step::before { left: 60px; border: medium solid white; border-width: 10px 10px 10px 0; border-color: transparent white transparent transparent; }
    .left::after, .right::after { left: 21px; }
    .right { left: 0%; }
    .hero h1 { font-size: 2.5rem; }
}