/* 
   Bangladesh Startup Ecosystem Report Website
   Main Stylesheet
   Author: Kalyanjit Hatibaruah
   © 2025 Flugelsoft Lab
*/

/* ===== Base Styles ===== */
:root {
    /* Color Variables */
    --color-primary: #1a365d;
    --color-secondary: #2c7a7b;
    --color-accent: #d69e2e;
    --color-background: #f7fafc;
    --color-text: #2d3748;
    --color-text-light: #718096;
    --color-white: #ffffff;
    --color-border: #e2e8f0;
    --color-gradient-start: #1a365d;
    --color-gradient-end: #2c7a7b;
    
    /* Typography */
    --font-heading: 'Montserrat', sans-serif;
    --font-body: 'Source Sans Pro', sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-xxl: 5rem;
    
    /* Container Width */
    --container-width: 1200px;
    
    /* Border Radius */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --border-radius-full: 50%;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-background);
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
    color: var(--color-primary);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
}

h2 {
    font-size: 2rem;
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

p {
    margin-bottom: var(--spacing-md);
}

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

a:hover {
    color: var(--color-primary);
}

ul, ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-lg);
}

img {
    max-width: 100%;
    height: auto;
}

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius-md);
    font-family: var(--font-heading);
    font-weight: 600;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
    color: var(--color-white);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--color-gradient-end), var(--color-gradient-start));
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
    background-color: var(--color-primary);
    color: var(--color-white);
    transform: translateY(-2px);
}

.btn-outline {
    background-color: transparent;
    color: var(--color-secondary);
    border: 1px solid var(--color-secondary);
    font-size: 0.9rem;
    padding: 0.5rem 1rem;
}

.btn-outline:hover {
    background-color: var(--color-secondary);
    color: var(--color-white);
}

/* ===== Header & Navigation ===== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--color-white);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    padding: var(--spacing-md) 0;
    transition: all var(--transition-normal);
}

.site-header.scrolled {
    padding: var(--spacing-sm) 0;
    box-shadow: var(--shadow-md);
}

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

.logo {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-text {
    background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin-left: var(--spacing-md);
}

.nav-menu a {
    color: var(--color-text);
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    transition: all var(--transition-fast);
}

.nav-menu a:hover {
    color: var(--color-secondary);
}

.nav-menu a.nav-cta {
    color: var(--color-accent);
    border: 1px solid var(--color-accent);
    border-radius: var(--border-radius-md);
}

.nav-menu a.nav-cta:hover {
    background-color: var(--color-accent);
    color: var(--color-white);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--color-primary);
    margin-bottom: 5px;
    border-radius: 3px;
    transition: all var(--transition-fast);
}

/* ===== Hero Section ===== */
.hero {
    padding: calc(var(--spacing-xxl) * 2) 0 var(--spacing-xxl);
    background: linear-gradient(135deg, rgba(26, 54, 93, 0.05), rgba(44, 122, 123, 0.05));
    margin-bottom: var(--spacing-xl);
}

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

.hero-content {
    flex: 1;
    max-width: 600px;
}

.hero h1 {
    margin-bottom: var(--spacing-md);
    font-size: 3rem;
    background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero .subtitle {
    font-size: 1.25rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-lg);
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
}

.hero-image {
    flex: 1;
    max-width: 500px;
    margin-left: var(--spacing-lg);
}

/* ===== Main Content Layout ===== */
.main-content {
    display: flex;
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.toc-sidebar {
    width: 280px;
    flex-shrink: 0;
}

.toc-container {
    position: sticky;
    top: 100px;
    padding: var(--spacing-md);
    background-color: var(--color-white);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-sm);
}

.toc-list {
    list-style: none;
    padding-left: 0;
    margin-bottom: var(--spacing-lg);
}

.toc-list li {
    margin-bottom: var(--spacing-xs);
}

.toc-list a {
    display: block;
    padding: var(--spacing-xs) 0;
    color: var(--color-text);
    font-size: 0.9rem;
    transition: all var(--transition-fast);
}

.toc-list a:hover {
    color: var(--color-secondary);
    transform: translateX(3px);
}

.toc-list a.active {
    color: var(--color-secondary);
    font-weight: 600;
}

.toc-list ul {
    list-style: none;
    padding-left: var(--spacing-md);
    margin-top: var(--spacing-xs);
    margin-bottom: var(--spacing-xs);
}

.toc-download {
    text-align: center;
    margin-top: var(--spacing-lg);
}

.report-content {
    flex: 1;
    margin-left: var(--spacing-xl);
}

/* ===== Report Sections ===== */
.report-section {
    margin-bottom: var(--spacing-xxl);
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.section-header {
    padding: var(--spacing-lg);
    background: linear-gradient(135deg, var(--color-gradient-start), var(--color-gradient-end));
    color: var(--color-white);
}

.section-header h2 {
    color: var(--color-white);
    margin-bottom: 0;
}

.section-content {
    padding: var(--spacing-lg);
}

.section-content h3 {
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    color: var(--color-primary);
}

.section-content h4 {
    margin-top: var(--spacing-md);
    color: var(--color-secondary);
}

/* ===== Info Cards ===== */
.info-card {
    background-color: rgba(44, 122, 123, 0.05);
    border-radius: var(--border-radius-md);
    margin: var(--spacing-lg) 0;
    overflow: hidden;
}

.info-card-header {
    background-color: var(--color-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
}

.info-card-header h4 {
    color: var(--color-white);
    margin-bottom: 0;
}

.info-card-content {
    padding: var(--spacing-md);
}

/* ===== Author Section ===== */
.author-section {
    margin-top: var(--spacing-xxl);
}

.author-profile {
    display: flex;
    gap: var(--spacing-xl);
}

.author-image {
    flex-shrink: 0;
    width: 200px;
    height: 200px;
    border-radius: var(--border-radius-full);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 4px solid var(--color-white);
}

.author-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.author-details {
    flex: 1;
}

.author-title {
    color: var(--color-secondary);
    font-weight: 600;
    margin-top: -0.5rem;
    margin-bottom: var(--spacing-md);
}

.expertise-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    list-style: none;
    padding-left: 0;
    margin-bottom: var(--spacing-md);
}

.expertise-list li {
    background-color: rgba(44, 122, 123, 0.1);
    color: var(--color-secondary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    font-size: 0.9rem;
}

.contact-list {
    list-style: none;
    padding-left: 0;
}

.contact-list li {
    margin-bottom: var(--spacing-xs);
}

.contact-list i {
    width: 20px;
    color: var(--color-secondary);
    margin-right: var(--spacing-sm);
}

/* ===== Footer ===== */
.site-footer {
    background-color: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-xxl);
}

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

.footer-logo {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
}

.footer-copyright {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

.footer-links ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.footer-links li {
    margin-left: var(--spacing-lg);
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    transition: color var(--transition-fast);
}

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

/* ===== Back to Top Button ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: var(--border-radius-full);
    background-color: var(--color-secondary);
    color: var(--color-white);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    border: none;
    box-shadow: var(--shadow-md);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--color-primary);
    transform: translateY(-3px);
}

/* ===== Responsive Styles ===== */
@media (max-width: 1024px) {
    .main-content {
        flex-direction: column;
    }
    
    .toc-sidebar {
        width: 100%;
        margin-bottom: var(--spacing-lg);
    }
    
    .toc-container {
        position: relative;
        top: 0;
    }
    
    .report-content {
        margin-left: 0;
    }
    
    .hero .container {
        flex-direction: column;
    }
    
    .hero-content {
        max-width: 100%;
        text-align: center;
    }
    
    .hero-cta {
        justify-content: center;
    }
    
    .hero-image {
        margin-left: 0;
        margin-top: var(--spacing-lg);
        max-width: 100%;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background-color: var(--color-white);
        flex-direction: column;
        align-items: center;
        padding: var(--spacing-md) 0;
        box-shadow: var(--shadow-md);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-normal);
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-menu li {
        margin: var(--spacing-xs) 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .author-profile {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .author-image {
        margin-bottom: var(--spacing-lg);
    }
    
    .expertise-list {
        justify-content: center;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-logo, .footer-copyright {
        margin-bottom: var(--spacing-md);
    }
    
    .footer-links ul {
        justify-content: center;
    }
    
    .footer-links li {
        margin: 0 var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero .subtitle {
        font-size: 1rem;
    }
    
    .hero-cta {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .section-header, .section-content {
        padding: var(--spacing-md);
    }
}