/* style.css - Clean, premium, accessible style guide for K-BridgeHealth */

/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Outfit:wght@300;400;500;600;700;800&display=swap');

/* Variables & Design System */
:root {
    --font-heading: 'SamsungOne', Arial, 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-body: 'SamsungOne', Arial, 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    
    /* Branding Colors */
    --color-navy: #000000;
    --color-indigo: #1428a0;
    --color-violet: #6C3AA8;
    --color-soft-blue: #F1F5F9;
    --color-soft-purple: #F8FAFC;
    --color-emerald: #059669;
    --color-emerald-light: #D1FAE5;
    
    /* Semantic Colors */
    --bg-primary: #F8F9FA;
    --bg-card: #FFFFFF;
    --text-primary: #000000;
    --text-secondary: #363636;
    --border-color: #E5E5E5;
    --color-accent: #1428a0;
    
    /* Utilities */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.05), 0 4px 6px -2px rgba(0,0,0,0.02);
    --transition-base: all 0.2s ease-in-out;
}

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

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

body {
    font-family: var(--font-body);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 1.125rem; /* 18px body text as recommended for seniors */
    -webkit-font-smoothing: antialiased;
    transition: var(--transition-base);
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--color-navy);
    font-weight: 700;
    line-height: 1.25;
    margin-bottom: 1rem;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; border-left: 5px solid var(--color-indigo); padding-left: 0.75rem; }
h3 { font-size: 1.5rem; }
p { margin-bottom: 1.25rem; color: var(--text-secondary); }

a {
    color: var(--color-indigo);
    text-decoration: none;
    transition: var(--transition-base);
    font-weight: 500;
}

a:hover {
    text-decoration: underline;
    color: var(--color-violet);
}

/* Accessible focus states for keyboard users */
a:focus, button:focus, input:focus, select:focus, textarea:focus {
    outline: 3px solid var(--color-violet);
    outline-offset: 2px;
}

/* Layout Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.grid {
    display: grid;
    gap: 1.5rem;
}

.grid-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }

/* Card styles */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.75rem;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-base);
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.card-title {
    color: var(--color-navy);
    margin-bottom: 0.75rem;
}

/* Button & Interactive styles (minimum 44px height) */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    border: 2px solid transparent;
    cursor: pointer;
    min-height: 48px; /* High target for accessibility */
    transition: var(--transition-base);
    text-decoration: none !important;
}

.btn-primary {
    background-color: var(--color-navy);
    color: #FFFFFF !important;
}

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

.btn-secondary {
    background-color: var(--color-soft-blue);
    color: var(--color-navy) !important;
    border: 2px solid var(--color-indigo);
}

.btn-secondary:hover {
    background-color: var(--color-indigo);
    color: #FFFFFF !important;
}

.btn-accent {
    background-color: var(--color-violet);
    color: #FFFFFF !important;
}

.btn-accent:hover {
    background-color: var(--color-indigo);
}

/* Header & Navigation */
header {
    background: #ffffff;
    border-bottom: 1px solid #eeeeee;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 1px 2px rgba(0,0,0,0.03);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 2rem;
}

.logo {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.35rem;
    color: #000000 !important;
    letter-spacing: -0.5px;
    text-decoration: none !important;
    white-space: nowrap;
    display: flex;
    align-items: center;
}

/* Remove dot, keep it clean */
.logo-dot {
    display: none !important;
}

nav#main-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 1;
}

nav#main-nav ul {
    list-style: none;
    display: flex;
    gap: 1.75rem;
    align-items: center;
    margin: 0;
    padding: 0;
}

nav#main-nav ul li a {
    color: #363636;
    font-size: 0.9rem;
    font-weight: 500;
    white-space: nowrap;
    text-decoration: none !important;
    padding: 0.5rem 0;
    position: relative;
    transition: color 0.15s ease-in-out;
}

nav#main-nav ul li a:hover {
    color: #000000;
}

/* Active navigation link indicator - clean bottom bar */
nav#main-nav ul li a.active-nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: #000000;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Clean CTA pill buttons in Samsung Business style */
.btn-nav-outline, .btn-nav-solid {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 38px;
    padding: 0 1.25rem;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 20px;
    text-decoration: none !important;
    white-space: nowrap;
    cursor: pointer;
    transition: all 0.15s ease-in-out;
}

.btn-nav-outline {
    background: transparent;
    color: #000000 !important;
    border: 1px solid #cccccc;
}

.btn-nav-outline:hover {
    border-color: #000000;
    background: #f5f5f5;
}

.btn-nav-solid {
    background: #000000;
    color: #ffffff !important;
    border: 1px solid #000000;
}

.btn-nav-solid:hover {
    background: #333333;
    border-color: #333333;
}

.lang-selector {
    display: inline-flex;
    align-items: center;
    border: 1px solid #cccccc;
    height: 38px;
    border-radius: 20px;
    padding: 0 0.75rem;
    background: #ffffff;
}

.lang-selector select {
    background: transparent;
    border: none;
    font-weight: 600;
    color: #000000;
    cursor: pointer;
    font-size: 0.85rem;
    outline: none;
}

.hamburger {
    display: none;
    background: none;
    border: none;
    font-size: 1.75rem;
    cursor: pointer;
    color: #000000;
    padding: 0.5rem;
}

.mobile-only-actions {
    display: none !important;
}

/* Hero Section */
.hero-section {
    padding: 4.5rem 0;
    background: linear-gradient(135deg, var(--color-soft-blue) 0%, #FFFFFF 100%);
    border-bottom: 1px solid var(--border-color);
}

.hero-layout {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 3rem;
    line-height: 1.15;
    margin-bottom: 1.5rem;
}

.hero-content p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.hero-visual {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 1.5rem;
    border: 1.5px solid var(--border-color);
}

/* Demo badge for safety notice */
.demo-badge {
    background-color: #FEF3C7;
    color: #92400E;
    font-size: 0.8rem;
    font-weight: 700;
    padding: 0.25rem 0.6rem;
    border-radius: 9999px;
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    margin-bottom: 1rem;
    border: 1px solid #F59E0B;
    text-transform: uppercase;
}

/* Multilingual display styling */
.multi-lang {
    display: block;
}

/* Default language visibility based on data-active attribute */
.multi-lang[data-active="en"] .lang-val:not(.lang-en) { display: none; }
.multi-lang[data-active="ko"] .lang-val:not(.lang-ko) { display: none; }
.multi-lang[data-active="zh"] .lang-val:not(.lang-zh) { display: none; }
.multi-lang[data-active="ja"] .lang-val:not(.lang-ja) { display: none; }

/* When multilingual-view-active is toggled, display ALL side-by-side */
body.multilingual-view-active .multi-lang {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    border-left: 2px dashed var(--color-indigo);
    padding-left: 0.75rem;
    margin: 0.5rem 0;
}

body.multilingual-view-active .multi-lang .lang-val {
    display: inline-block !important;
    position: relative;
    padding-left: 2.25rem;
    margin-bottom: 0.25rem;
}

body.multilingual-view-active .multi-lang .lang-val::before {
    content: attr(lang);
    text-transform: uppercase;
    font-size: 0.7rem;
    font-weight: 800;
    color: #FFFFFF;
    background: var(--color-indigo);
    padding: 0.15rem 0.35rem;
    border-radius: 4px;
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 1.5rem;
    text-align: center;
}

body.multilingual-view-active .multi-lang .lang-val[lang="ko"]::before {
    background: #E11D48; /* Red for Korean badge */
}

body.multilingual-view-active .multi-lang .lang-val[lang="zh"]::before {
    background: #D97706; /* Amber for Chinese badge */
}

body.multilingual-view-active .multi-lang .lang-val[lang="ja"]::before {
    background: #059669; /* Emerald for Japanese badge */
}

/* Accessibility high contrast mode stylesheet overrides */
body.accessibility-high-contrast {
    background-color: #000000 !important;
    color: #FFFF00 !important;
}

body.accessibility-high-contrast h1, 
body.accessibility-high-contrast h2, 
body.accessibility-high-contrast h3, 
body.accessibility-high-contrast h4, 
body.accessibility-high-contrast h5, 
body.accessibility-high-contrast h6, 
body.accessibility-high-contrast p, 
body.accessibility-high-contrast span, 
body.accessibility-high-contrast div, 
body.accessibility-high-contrast li, 
body.accessibility-high-contrast label, 
body.accessibility-high-contrast header, 
body.accessibility-high-contrast nav a, 
body.accessibility-high-contrast footer {
    background-color: #000000 !important;
    color: #FFFF00 !important;
    border-color: #FFFF00 !important;
    text-shadow: none !important;
    box-shadow: none !important;
}

body.accessibility-high-contrast .btn, 
body.accessibility-high-contrast input, 
body.accessibility-high-contrast select, 
body.accessibility-high-contrast textarea, 
body.accessibility-high-contrast .card {
    background: #000000 !important;
    color: #FFFF00 !important;
    border: 2px solid #FFFF00 !important;
    outline: none !important;
}

body.accessibility-high-contrast .btn:hover {
    background: #FFFF00 !important;
    color: #000000 !important;
}

body.accessibility-high-contrast a {
    color: #FFFF00 !important;
    text-decoration: underline !important;
}

/* OpenDyslexic fallback font styling */
body.dyslexia-font {
    font-family: 'Comic Sans MS', 'Trebuchet MS', sans-serif !important;
    word-spacing: 0.15em;
    letter-spacing: 0.05em;
}

/* Accessibility widget CSS */
#accessibility-widget {
    position: fixed;
    bottom: 25px;
    right: 25px;
    z-index: 10000;
    font-family: var(--font-body);
}

#acy-fab {
    background-color: var(--color-indigo);
    color: #FFFFFF;
    border: none;
    border-radius: 9999px;
    padding: 0.75rem 1.25rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    min-height: 48px;
    transition: var(--transition-base);
}

#acy-fab:hover {
    background-color: var(--color-navy);
    transform: scale(1.05);
}

#acy-fab svg {
    width: 24px;
    height: 24px;
}

#acy-panel {
    display: none;
    position: absolute;
    bottom: 60px;
    right: 0;
    width: 320px;
    background: #FFFFFF;
    border: 2px solid var(--color-navy);
    border-radius: var(--radius-md);
    box-shadow: 0 10px 25px rgba(0,0,0,0.25);
    overflow: hidden;
    color: var(--text-primary);
}

#acy-panel.open {
    display: block;
}

.acy-header {
    background: var(--color-navy);
    color: #FFFFFF;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.acy-header h2 {
    font-size: 1.15rem;
    margin: 0;
    color: #FFFFFF;
    border-left: none;
    padding-left: 0;
}

#acy-close {
    background: transparent;
    border: none;
    color: #FFFFFF;
    font-size: 1.5rem;
    cursor: pointer;
    font-weight: 700;
}

.acy-body {
    padding: 1.25rem;
    max-height: 450px;
    overflow-y: auto;
}

.acy-control-group {
    margin-bottom: 1.25rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
}

.acy-control-group:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.acy-label {
    display: block;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--color-navy);
}

.acy-btn-row {
    display: flex;
    gap: 0.5rem;
}

.acy-btn {
    flex: 1;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    cursor: pointer;
    text-align: center;
    color: var(--text-primary);
    transition: var(--transition-base);
    min-height: 40px;
}

.acy-btn:hover {
    background: var(--color-soft-blue);
    border-color: var(--color-indigo);
}

.acy-btn.active {
    background: var(--color-indigo);
    color: #FFFFFF;
    border-color: var(--color-indigo);
}

.acy-toggle-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.acy-toggle {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.acy-help-text {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
    margin-bottom: 0;
}

.acy-guide-list {
    font-size: 0.85rem;
    padding-left: 1.25rem;
    color: var(--text-secondary);
}

.acy-guide-list li {
    margin-bottom: 0.25rem;
}

/* Sections & Typography defaults */
.challenge-section, .approach-section, .tech-section, .demo-section, .aims-section, .audience-section, .partnership-section {
    padding: 4.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.tech-section {
    background: #FFFFFF;
}

.section-tag {
    text-transform: uppercase;
    font-weight: 700;
    color: var(--color-violet);
    font-size: 0.9rem;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
    display: block;
}

.section-title {
    margin-bottom: 2.5rem;
    text-align: center;
}

.section-title h2 {
    display: inline-block;
}

/* Technical Architecture Flowchart */
.flowchart-wrapper {
    background: var(--color-soft-blue);
    border-radius: var(--radius-lg);
    padding: 2.5rem 1.5rem;
    border: 1.5px solid var(--border-color);
    margin-top: 2rem;
}

.flow-step {
    background: #FFFFFF;
    padding: 1.25rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    text-align: center;
    position: relative;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-base);
}

.flow-step:hover {
    border-color: var(--color-indigo);
    box-shadow: var(--shadow-md);
}

.flow-step h4 {
    color: var(--color-indigo);
    margin-bottom: 0.25rem;
}

.flow-arrow {
    text-align: center;
    font-size: 1.75rem;
    color: var(--color-indigo);
    margin: 0.5rem 0;
    font-weight: 800;
}

/* Tooltips */
.tooltip {
    position: relative;
    display: inline-block;
    cursor: help;
    border-bottom: 1px dotted var(--color-indigo);
}

.tooltip .tooltiptext {
    visibility: hidden;
    width: 260px;
    background-color: var(--color-navy);
    color: #fff;
    text-align: left;
    border-radius: 6px;
    padding: 1rem;
    position: absolute;
    z-index: 1000;
    bottom: 125%;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    transition: opacity 0.2s;
    font-size: 0.85rem;
    line-height: 1.4;
    box-shadow: var(--shadow-lg);
}

.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}

/* Footer rules */
footer {
    background: var(--color-navy);
    color: #E2E8F0;
    padding: 3rem 0;
    font-size: 0.95rem;
}

footer a {
    color: #93C5FD;
}

footer a:hover {
    color: #FFFFFF;
}

.footer-disclaimer {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 1.5rem;
    margin-top: 1.5rem;
    font-size: 0.85rem;
    color: #94A3B8;
}

/* Mobile responsive fixes */
@media (max-width: 768px) {
    html { font-size: 15px; }
    h1 { font-size: 2.25rem; }
    h2 { font-size: 1.75rem; }
    .hero-layout {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .desktop-only-actions {
        display: none !important;
    }
    .mobile-only-actions {
        display: flex !important;
        flex-direction: column;
        gap: 0.75rem;
        margin-top: 1.25rem;
        border-top: 1px solid #e2e8f0;
        padding-top: 1.25rem;
        width: 100%;
    }
    .mobile-only-actions .btn-nav-outline,
    .mobile-only-actions .btn-nav-solid,
    .mobile-only-actions .lang-selector {
        width: 100%;
        justify-content: center;
        box-sizing: border-box;
    }
    .mobile-only-actions .lang-selector select {
        text-align: center;
        text-align-last: center;
    }
    .hamburger {
        display: block !important;
    }
    nav#main-nav ul {
        display: none;
        flex-direction: column;
        align-items: flex-start;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: #FFFFFF;
        border-bottom: 1.5px solid var(--border-color);
        padding: 1.5rem;
        box-shadow: var(--shadow-md);
        gap: 1rem;
        z-index: 999;
    }
    nav#main-nav.mobile-open ul {
        display: flex;
    }
    .hero-actions {
        flex-direction: column;
    }
    .hero-actions .btn {
        width: 100%;
    }
}