/* ===================================
   QualifyMD - Main Stylesheet
   Modern, Clean, Medical-themed Design
   =================================== */

/* CSS Variables - Light Mode (default) */
:root {
    /* Colors */
    --primary: #0066CC;
    --primary-dark: #004C99;
    --primary-light: #E6F0FA;
    --secondary: #00A878;
    --secondary-dark: #008060;
    --accent: #FF6B6B;
    --dark: #1A1A2E;
    --dark-light: #2D2D44;
    --gray-900: #111827;
    --gray-800: #1F2937;
    --gray-700: #374151;
    --gray-600: #4B5563;
    --gray-500: #6B7280;
    --gray-400: #9CA3AF;
    --gray-300: #D1D5DB;
    --gray-200: #E5E7EB;
    --gray-100: #F3F4F6;
    --gray-50: #F9FAFB;
    --white: #FFFFFF;
    --success: #10B981;
    --warning: #F59E0B;
    --error: #EF4444;

    /* Theme-specific colors */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F9FAFB;
    --bg-tertiary: #F3F4F6;
    --bg-card: #FFFFFF;
    --bg-header: rgba(255, 255, 255, 0.95);
    --text-primary: #1A1A2E;
    --text-secondary: #4B5563;
    --text-tertiary: #6B7280;
    --border-color: #E5E7EB;
    --shadow-color: rgba(0, 0, 0, 0.1);

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #0066CC 0%, #00A878 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-dark: linear-gradient(135deg, #1A1A2E 0%, #2D2D44 100%);
    --gradient-hero-bg: linear-gradient(180deg, var(--gray-50) 0%, var(--white) 100%);

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --font-size-6xl: 3.75rem;

    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    --spacing-20: 5rem;
    --spacing-24: 6rem;

    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
}

/* Dark Mode */
[data-theme="dark"] {
    --primary: #4D9FFF;
    --primary-dark: #3385FF;
    --primary-light: #1A2A3D;
    --secondary: #00D99A;
    --secondary-dark: #00B880;
    
    --dark: #E5E7EB;
    --dark-light: #D1D5DB;
    --gray-900: #F9FAFB;
    --gray-800: #F3F4F6;
    --gray-700: #E5E7EB;
    --gray-600: #D1D5DB;
    --gray-500: #9CA3AF;
    --gray-400: #6B7280;
    --gray-300: #4B5563;
    --gray-200: #374151;
    --gray-100: #1F2937;
    --gray-50: #111827;
    --white: #0D1117;
    
    /* Theme-specific colors */
    --bg-primary: #0D1117;
    --bg-secondary: #161B22;
    --bg-tertiary: #21262D;
    --bg-card: #161B22;
    --bg-header: rgba(13, 17, 23, 0.95);
    --text-primary: #E6EDF3;
    --text-secondary: #8B949E;
    --text-tertiary: #6E7681;
    --border-color: #30363D;
    --shadow-color: rgba(0, 0, 0, 0.4);
    
    --gradient-hero-bg: linear-gradient(180deg, #161B22 0%, #0D1117 100%);
}

/* Reset & Base Styles */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-secondary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition-base), color var(--transition-base);
}

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

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

ul {
    list-style: none;
}

/* Container */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-6);
}

/* ===================================
   Header & Navigation
   =================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--bg-header);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: var(--spacing-8);
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    font-weight: 700;
    font-size: var(--font-size-xl);
    color: var(--text-primary);
}

.logo-icon {
    font-size: var(--font-size-2xl);
}

.nav-links {
    display: flex;
    gap: var(--spacing-8);
}

.nav-links a {
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

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

.nav-actions {
    display: flex;
    gap: var(--spacing-3);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-2);
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

/* Theme Toggle Button */
.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-left: auto;
}

.theme-toggle:hover {
    background: var(--primary-light);
    border-color: var(--primary);
}

.theme-toggle .icon {
    font-size: 18px;
    line-height: 1;
}

.theme-toggle .icon-sun {
    display: none;
}

.theme-toggle .icon-moon {
    display: block;
}

[data-theme="dark"] .theme-toggle .icon-sun {
    display: block;
}

[data-theme="dark"] .theme-toggle .icon-moon {
    display: none;
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-3) var(--spacing-5);
    font-family: var(--font-family);
    font-size: var(--font-size-sm);
    font-weight: 600;
    border-radius: var(--radius-lg);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

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

.btn-outline {
    background: transparent;
    border-color: var(--border-color);
    color: var(--text-primary);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.btn-white {
    background: var(--white);
    color: var(--primary);
}

.btn-white:hover {
    background: var(--gray-100);
    transform: translateY(-1px);
}

.btn-outline-white {
    background: transparent;
    border-color: rgba(255, 255, 255, 0.5);
    color: var(--white);
}

.btn-outline-white:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--white);
}

.btn-lg {
    padding: var(--spacing-4) var(--spacing-8);
    font-size: var(--font-size-base);
}

.btn-block {
    width: 100%;
}

.play-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: var(--primary-light);
    border-radius: var(--radius-full);
    font-size: 10px;
    color: var(--primary);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    position: relative;
    padding: calc(72px + var(--spacing-20)) 0 var(--spacing-20);
    overflow: hidden;
    background: var(--gradient-hero-bg);
    transition: background var(--transition-base);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-16);
    align-items: center;
}

.hero-badge {
    display: inline-block;
    padding: var(--spacing-2) var(--spacing-4);
    background: var(--primary-light);
    color: var(--primary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-6);
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 800;
    line-height: 1.1;
    color: var(--text-primary);
    margin-bottom: var(--spacing-6);
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-8);
    max-width: 540px;
}

.hero-actions {
    display: flex;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-12);
}

.hero-stats {
    display: flex;
    gap: var(--spacing-10);
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    color: var(--text-primary);
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

.hero-image {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
}

.hero-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-6);
    box-shadow: var(--shadow-xl);
    min-width: 280px;
    transition: background-color var(--transition-base);
}

.hero-card.floating {
    position: absolute;
    top: 20%;
    right: 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    padding: var(--spacing-4) var(--spacing-5);
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.card-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
    margin-bottom: var(--spacing-4);
}

.card-badge {
    padding: var(--spacing-1) var(--spacing-3);
    font-size: var(--font-size-xs);
    font-weight: 600;
    border-radius: var(--radius-full);
}

.card-badge.active {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.card-title {
    font-weight: 600;
    color: var(--text-primary);
}

.progress-bar {
    height: 8px;
    background: var(--border-color);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--spacing-2);
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

.progress-text {
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

.cert-icon {
    font-size: var(--font-size-2xl);
}

.cert-text {
    font-weight: 600;
    color: var(--success);
}

.hero-bg-gradient {
    position: absolute;
    top: 0;
    right: 0;
    width: 50%;
    height: 100%;
    background: radial-gradient(circle at 70% 30%, rgba(0, 102, 204, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

/* ===================================
   Section Styles
   =================================== */
section {
    padding: var(--spacing-24) 0;
}

.section-header {
    text-align: center;
    max-width: 640px;
    margin: 0 auto var(--spacing-16);
}

.section-badge {
    display: inline-block;
    padding: var(--spacing-2) var(--spacing-4);
    background: var(--primary-light);
    color: var(--primary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-4);
}

.section-title {
    font-size: var(--font-size-4xl);
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: var(--spacing-4);
}

.section-description {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
}

/* ===================================
   Features Section
   =================================== */
.features {
    background: var(--bg-primary);
    transition: background-color var(--transition-base);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-8);
}

.feature-card {
    padding: var(--spacing-8);
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
}

.feature-card:hover {
    background: var(--bg-card);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--primary-light);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-2xl);
    margin-bottom: var(--spacing-5);
}

.feature-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-3);
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===================================
   Certifications Section
   =================================== */
.certifications {
    background: var(--bg-secondary);
    transition: background-color var(--transition-base);
}

.cert-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-8);
}

.cert-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-8);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.cert-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.cert-card.featured {
    border: 2px solid var(--primary);
}

.cert-card.featured::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
}

.cert-header {
    margin-bottom: var(--spacing-4);
}

.cert-badge {
    display: inline-block;
    padding: var(--spacing-1) var(--spacing-3);
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-size: var(--font-size-xs);
    font-weight: 600;
    border-radius: var(--radius-full);
}

.cert-card.featured .cert-badge {
    background: var(--primary-light);
    color: var(--primary);
}

.cert-icon-large {
    font-size: 48px;
    margin-bottom: var(--spacing-4);
}

.cert-name {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-3);
}

.cert-desc {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-5);
    line-height: 1.6;
}

.cert-features {
    margin-bottom: var(--spacing-6);
}

.cert-features li {
    padding: var(--spacing-2) 0;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.cert-cta {
    text-align: center;
    margin-top: var(--spacing-12);
}

.cert-cta p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-4);
}

/* ===================================
   How It Works Section
   =================================== */
.how-it-works {
    background: var(--bg-primary);
    transition: background-color var(--transition-base);
}

.steps-container {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: var(--spacing-4);
}

.step {
    flex: 1;
    max-width: 300px;
    text-align: center;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    color: var(--white);
    font-size: var(--font-size-2xl);
    font-weight: 800;
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-6);
}

.step-connector {
    flex: 0 0 80px;
    height: 2px;
    background: var(--border-color);
    margin-top: 32px;
}

.step-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-3);
}

.step-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===================================
   Testimonials Section
   =================================== */
.testimonials {
    background: var(--bg-secondary);
    transition: background-color var(--transition-base);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-8);
}

.testimonial-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-8);
    box-shadow: var(--shadow-md);
}

.testimonial-content {
    margin-bottom: var(--spacing-6);
}

.testimonial-content p {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    line-height: 1.7;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--spacing-4);
}

.author-avatar {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--gradient-primary);
    color: var(--white);
    font-weight: 700;
    border-radius: var(--radius-full);
}

.author-info {
    display: flex;
    flex-direction: column;
}

.author-name {
    font-weight: 600;
    color: var(--text-primary);
}

.author-title {
    font-size: var(--font-size-sm);
    color: var(--text-tertiary);
}

/* ===================================
   CTA Section
   =================================== */
.cta {
    background: var(--gradient-primary);
    padding: var(--spacing-20) 0;
}

.cta-content {
    text-align: center;
    max-width: 640px;
    margin: 0 auto;
}

.cta-title {
    font-size: var(--font-size-4xl);
    font-weight: 800;
    color: var(--white);
    margin-bottom: var(--spacing-4);
}

.cta-description {
    font-size: var(--font-size-lg);
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--spacing-8);
}

.cta-actions {
    display: flex;
    justify-content: center;
    gap: var(--spacing-4);
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: #0D1117;
    color: var(--gray-400);
    padding: var(--spacing-16) 0 var(--spacing-8);
    transition: background-color var(--transition-base);
}

[data-theme="dark"] .footer {
    background: #000000;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--spacing-12);
    margin-bottom: var(--spacing-12);
}

.footer-brand .logo {
    color: var(--white);
    margin-bottom: var(--spacing-4);
}

.footer-tagline {
    margin-bottom: var(--spacing-6);
    line-height: 1.7;
}

.social-links {
    display: flex;
    gap: var(--spacing-4);
}

.social-links a {
    font-size: var(--font-size-xl);
    transition: transform var(--transition-fast);
}

.social-links a:hover {
    transform: scale(1.1);
}

.footer-links h4 {
    color: var(--white);
    font-weight: 600;
    margin-bottom: var(--spacing-5);
}

.footer-links li {
    margin-bottom: var(--spacing-3);
}

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

.footer-bottom {
    padding-top: var(--spacing-8);
    border-top: 1px solid #30363D;
    text-align: center;
    font-size: var(--font-size-sm);
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-description {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-image {
        display: none;
    }

    .features-grid,
    .cert-grid,
    .testimonials-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-5xl: 2.5rem;
        --font-size-4xl: 2rem;
        --font-size-3xl: 1.5rem;
    }

    .nav-links,
    .nav-actions {
        display: none;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero-title {
        font-size: var(--font-size-4xl);
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--spacing-6);
    }

    .features-grid,
    .cert-grid,
    .testimonials-grid {
        grid-template-columns: 1fr;
    }

    .steps-container {
        flex-direction: column;
        align-items: center;
    }

    .step-connector {
        width: 2px;
        height: 40px;
        margin: 0;
    }

    .cta-actions {
        flex-direction: column;
        align-items: center;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .social-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-4);
    }

    section {
        padding: var(--spacing-16) 0;
    }

    .section-header {
        margin-bottom: var(--spacing-10);
    }

    .feature-card,
    .cert-card,
    .testimonial-card {
        padding: var(--spacing-6);
    }
}