/* 
 * Jithin Antony - Portfolio Stylesheet
 * Custom Dark-Theme-First Design System
 * Vanilla CSS (No Tailwind)
 */

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700;800&family=IBM+Plex+Sans:wght@300;400;500;600;700&family=Inter:wght@300;400;500;600;700&family=Outfit:wght@300;400;500;600;700;800&display=swap');

:root {
    /* Color Palette - Indigo Theme (Dark theme default) */
    --color-bg-primary: #13111f;
    --color-bg-secondary: #1c192d;
    --color-surface: #1c192d;
    --color-surface-hover: #24203a;
    --color-border: #2b2744;
    --color-card-bg: rgba(28, 25, 45, 0.6);
    --color-navbar-bg: rgba(19, 17, 31, 0.75);
    
    --color-text-primary: #f2f1f5;
    --color-text-secondary: #bebcbf;
    --color-text-muted: #8c8a8f;
    
    --color-accent: #6c5ce7; /* Indigo/Purple accent */
    --color-accent-rgb: 108, 92, 231;
    --color-accent-hover: #5f27cd;
    
    --color-success: #22c55e;
    --color-success-rgb: 34, 197, 94;
    --color-danger: #ef4444;
    --color-danger-rgb: 239, 68, 68;
    --color-warning: #f59e0b;
    --color-warning-rgb: 245, 158, 11;
    /* Readable text variants of the semantic colors (Tailwind -400 on dark) */
    --color-success-text: #4ade80;
    --color-danger-text: #f87171;
    --color-warning-text: #fbbf24;
    
    /* Typography */
    --font-sans: 'Inter', sans-serif;
    --font-heading: 'Poppins', 'Outfit', sans-serif;
    --font-mono: 'IBM Plex Sans', monospace;
    
    /* Shape & Borders */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-full: 9999px;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 3rem;
    --space-xxl: 6rem;
    
    /* Effects */
    --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 -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.3);
    --backdrop-blur: blur(16px);
    
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light Theme Variables Override */
html.light-mode {
    --color-bg-primary: #fafaff;
    --color-bg-secondary: #f0effc;
    --color-surface: #ffffff;
    --color-surface-hover: #e8e6fa;
    --color-border: #e0ddf5;
    --color-card-bg: rgba(255, 255, 255, 0.7);
    --color-navbar-bg: rgba(250, 250, 255, 0.8);
    
    --color-text-primary: #232229;
    --color-text-secondary: #6a6875;
    --color-text-muted: #a5a3ab;

    /* Semantic text shades darken for light backgrounds (Tailwind -700) */
    --color-success-text: #15803d;
    --color-danger-text: #b91c1c;
    --color-warning-text: #b45309;

    --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.05), 0 4px 6px -4px rgba(15, 23, 42, 0.05);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    height: 100%;
}

body {
    background-color: var(--color-bg-primary);
    color: var(--color-text-primary);
    font-family: var(--font-sans);
    font-size: 0.9rem;
    line-height: 1.6;
    overflow-x: hidden;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    transition: background-color var(--transition-smooth), color var(--transition-smooth);
}

/* Scrollbar Customization */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--color-bg-primary);
}
::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--color-accent);
}

/* Typography Hierarchy */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-text-primary);
    margin-bottom: var(--space-sm);
}

h1 { font-size: 2.2rem; }
h2 { font-size: 1.65rem; }
h3 { font-size: 1.3rem; }
h4 { font-size: 1.1rem; }
h5 { font-size: 0.95rem; }

p {
    margin-bottom: var(--space-md);
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
}

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

/* Layout Utilities */
.container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section {
    padding: var(--space-xxl) 0;
    border-bottom: 1px solid var(--color-border);
}

.text-center { text-align: center; }

/* Sticky Glassmorphic Header Navigation */
.navbar-sticky {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: var(--color-navbar-bg) !important;
    backdrop-filter: var(--backdrop-blur);
    -webkit-backdrop-filter: var(--backdrop-blur);
    border-bottom: 1px solid var(--color-border);
    transition: var(--transition-smooth);
}

.navbar-sticky .navbar-brand {
    color: var(--color-text-primary) !important;
}

.navbar-sticky .nav-link {
    color: var(--color-text-secondary) !important;
    font-weight: 500;
    transition: var(--transition-fast);
}

.navbar-sticky .nav-link:hover,
.navbar-sticky .nav-link.active {
    color: var(--color-accent) !important;
}

/* Theme-aware hamburger icon.
   Bootstrap's navbar-dark renders the toggler icon white, which is invisible
   against the light navbar in light mode. Recolor it to the current text color. */
.navbar-toggler {
    padding: 0.4rem 0.6rem;
}
.navbar-toggler:focus {
    box-shadow: 0 0 0 2px rgba(var(--color-accent-rgb), 0.4);
}
.navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='%23f2f1f5' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2.2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") !important;
}
html.light-mode .navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='%23232229' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2.2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e") !important;
}

/* Cards (Glassmorphism Effects) */
.card-glass {
    background: var(--color-card-bg);
    backdrop-filter: var(--backdrop-blur);
    -webkit-backdrop-filter: var(--backdrop-blur);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    transition: var(--transition-smooth);
}
.card-glass:hover {
    border-color: var(--color-accent);
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

/* Floating Social Bar */
.social-floating-bar {
    position: fixed;
    left: 2rem;
    bottom: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
    z-index: 100;
}
.social-floating-bar a {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    transition: var(--transition-fast);
}
.social-floating-bar a:hover {
    color: var(--color-accent);
    transform: translateY(-3px);
}
.social-floating-bar::after {
    content: '';
    width: 1px;
    height: 80px;
    background-color: var(--color-border);
}

/* Scroll Down Indicator */
.scroll-down-wrapper {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
}
.scroll-down-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.4rem;
    color: var(--color-text-secondary);
    font-size: 0.75rem;
    font-family: var(--font-sans);
    font-weight: 500;
    letter-spacing: 1px;
    transition: var(--transition-fast);
    text-transform: uppercase;
}
.scroll-down-link:hover {
    color: var(--color-accent);
}
.mouse-icon {
    width: 20px;
    height: 32px;
    border: 2px solid var(--color-text-secondary);
    border-radius: 10px;
    position: relative;
    display: inline-block;
}
.mouse-wheel {
    width: 4px;
    height: 8px;
    background-color: var(--color-accent);
    border-radius: 2px;
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    animation: scrollMouse 1.5s infinite;
}
@keyframes scrollMouse {
    0% { opacity: 1; top: 6px; }
    50% { opacity: 0.3; top: 14px; }
    100% { opacity: 0; top: 14px; }
}
.scroll-arrow {
    font-size: 0.7rem;
    animation: bounceArrow 1.5s infinite;
}
@keyframes bounceArrow {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(4px); }
}

/* Alternating Timeline Layout */
.timeline-container {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: var(--space-md) 0;
}
.timeline-container::before {
    content: '';
    position: absolute;
    left: 50%;
    width: 2px;
    height: 100%;
    background-color: var(--color-border);
    transform: translateX(-50%);
}
.timeline-item {
    width: 50%;
    margin-bottom: var(--space-xl);
    position: relative;
}
.timeline-item.left {
    align-self: flex-start;
    padding-right: 40px;
}
.timeline-item.right {
    align-self: flex-end;
    padding-left: 40px;
}
.timeline-dot {
    position: absolute;
    top: 28px;
    width: 18px;
    height: 18px;
    background-color: var(--color-bg-primary);
    border: 3px solid var(--color-accent);
    border-radius: var(--radius-full);
    z-index: 5;
    transition: var(--transition-smooth);
}
.timeline-item.left .timeline-dot {
    right: -9px;
}
.timeline-item.right .timeline-dot {
    left: -9px;
}
.timeline-item:hover .timeline-dot {
    background-color: var(--color-accent);
    box-shadow: 0 0 0 6px rgba(var(--color-accent-rgb), 0.25);
}
@media (max-width: 991px) {
    .timeline-container::before {
        left: 10px;
    }
    .timeline-item {
        width: 100%;
        margin-bottom: var(--space-lg);
    }
    .timeline-item.left {
        align-self: flex-start;
        padding-left: 30px;
        padding-right: 0;
    }
    .timeline-item.right {
        align-self: flex-start;
        padding-left: 30px;
        padding-right: 0;
    }
    .timeline-item.left .timeline-dot,
    .timeline-item.right .timeline-dot {
        left: 1px;
        right: auto;
    }
    .social-floating-bar {
        display: none !important;
    }
}

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

.animate-fade-in {
    animation: fadeInUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes pulseGlow {
    0% { box-shadow: 0 0 0 0 rgba(var(--color-accent-rgb), 0.4); }
    70% { box-shadow: 0 0 0 8px rgba(var(--color-accent-rgb), 0); }
    100% { box-shadow: 0 0 0 0 rgba(var(--color-accent-rgb), 0); }
}

.pulse-glow {
    animation: pulseGlow 2s infinite;
}

/* Public Modal Layouts */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(2, 6, 23, 0.8);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 2000;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.modal-container {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 900px;
    max-height: 85vh;
    overflow-y: auto;
    position: relative;
    padding: var(--space-xl);
    box-shadow: var(--shadow-lg);
    transform: scale(0.9);
    transition: transform var(--transition-smooth);
}

.modal-overlay.active .modal-container {
    transform: scale(1);
}

.modal-close {
    position: absolute;
    top: var(--space-md);
    right: var(--space-md);
    font-size: 2rem;
    color: var(--color-text-secondary);
    background: none;
    border: none;
    cursor: pointer;
    transition: var(--transition-fast);
}

.modal-close:hover {
    color: var(--color-text-primary);
}

/* Narrow, compact variant for the contact form modal */
.modal-container--narrow {
    max-width: 600px;
    padding: var(--space-lg);
}

/* Bootstrap Utility Overrides for Custom Theme Mappings */
.text-secondary {
    color: var(--color-text-secondary) !important;
}
.text-muted {
    color: var(--color-text-muted) !important;
}
.bg-dark {
    background-color: var(--color-bg-secondary) !important;
}
.border-secondary {
    border-color: var(--color-border) !important;
}
.bg-secondary {
    background-color: var(--color-surface) !important;
}
.text-light {
    color: var(--color-text-primary) !important;
}
.text-info {
    color: var(--color-accent) !important;
}
.bg-info {
    background-color: var(--color-accent) !important;
}
.btn-info {
    background-color: var(--color-accent) !important;
    border-color: var(--color-accent) !important;
    color: #ffffff !important;
}
.btn-info:hover, .btn-info:focus, .btn-info:active {
    background-color: var(--color-accent-hover) !important;
    border-color: var(--color-accent-hover) !important;
    color: #ffffff !important;
}
.btn-outline-secondary {
    border-color: var(--color-border) !important;
    color: var(--color-text-primary) !important;
}
.btn-outline-secondary:hover {
    background-color: var(--color-border) !important;
    color: var(--color-text-primary) !important;
}
.text-success {
    color: var(--color-success-text) !important;
}
.text-danger {
    color: var(--color-danger-text) !important;
}
.text-warning {
    color: var(--color-warning-text) !important;
}
.alert-success {
    background-color: rgba(var(--color-success-rgb), 0.12) !important;
    border-color: rgba(var(--color-success-rgb), 0.35) !important;
    color: var(--color-success-text) !important;
}
.alert-danger {
    background-color: rgba(var(--color-danger-rgb), 0.12) !important;
    border-color: rgba(var(--color-danger-rgb), 0.35) !important;
    color: var(--color-danger-text) !important;
}

/* Project-card hover dim. A translucent layer can't be built from Bootstrap's
   bg-dark + bg-opacity utilities here: the themed .bg-dark override is solid
   and !important (same failure mode documented at .contact-icon below). */
.hover-overlay {
    background-color: rgba(2, 6, 23, 0.75);
}

/* About Profile Image */
.about-img-container {
    position: relative;
    max-width: 280px;
    width: 100%;
    margin: 0 auto;
}

.about-img-container::before {
    content: '';
    position: absolute;
    inset: 0;
    border: 2px solid var(--color-accent);
    border-radius: var(--radius-lg);
    transform: translate(8px, 8px);
    transition: var(--transition-smooth);
    z-index: 1;
    pointer-events: none;
}

.about-img-container:hover::before {
    transform: translate(4px, 4px);
    border-color: var(--color-accent-hover);
}

.about-img {
    position: relative;
    border-radius: var(--radius-lg);
    width: 100%;
    height: auto;
    object-fit: cover;
    z-index: 2;
    transition: var(--transition-smooth);
    border: 1px solid var(--color-border);
    background-color: var(--color-card-bg);
}

.about-img-container:hover .about-img {
    transform: translate(-4px, -4px);
}

/* Contact info icons (Get in Touch).
   Bootstrap's bg-opacity is defeated by the themed .bg-info !important override,
   which made the circle a solid accent block with a same-colour (invisible) icon.
   This dedicated class restores the intended tinted circle + visible accent icon. */
.contact-icon {
    width: 50px;
    height: 50px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background-color: rgba(var(--color-accent-rgb), 0.12);
    color: var(--color-accent);
    font-size: 1.1rem;
    transition: var(--transition-fast);
}
.card-glass:hover .contact-icon {
    background-color: rgba(var(--color-accent-rgb), 0.2);
}

/* ---------------------------------------------------------------
   Accessibility & UX hardening (added in responsive/QA audit)
   --------------------------------------------------------------- */

/* Lock background scroll while the project modal is open */
html.modal-open {
    overflow: hidden;
}

/* Visible keyboard focus for interactive elements */
a:focus-visible,
button:focus-visible,
.btn:focus-visible,
.form-control:focus-visible,
.filter-btn:focus-visible,
.nav-link:focus-visible,
.modal-close:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* Comfortable touch targets on touch/coarse-pointer devices */
@media (pointer: coarse) {
    .filter-btn {
        min-height: 40px;
        display: inline-flex;
        align-items: center;
    }
    .navbar-nav .nav-link {
        padding-top: 0.65rem;
        padding-bottom: 0.65rem;
    }
    .social-floating-bar a,
    footer .d-inline-flex a {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        min-width: 40px;
        min-height: 40px;
    }
}

/* Respect users who prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
    }
}

/* --- Contact form: honeypot (hidden from humans, visible to bots) --- */
.hp-field {
    position: absolute !important;
    left: -9999px !important;
    top: auto;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

/* --- Contact form: inline validation states on the dark inputs --- */
#contactForm .form-control.is-invalid {
    /* !important needed to beat the themed .border-secondary utility override */
    border-color: var(--color-danger) !important;
    background-image: none; /* drop Bootstrap's default icon on the dark theme */
    padding-right: 0.9rem;
    box-shadow: 0 0 0 0.15rem rgba(var(--color-danger-rgb), 0.2);
}
#contactForm .form-control.is-invalid:focus {
    box-shadow: 0 0 0 0.2rem rgba(var(--color-danger-rgb), 0.3);
}
#contactForm .invalid-feedback {
    display: none;
    margin-top: 0.3rem;
    font-size: 0.72rem;
    font-family: var(--font-mono);
    letter-spacing: 0.2px;
    color: var(--color-danger-text);
}
#contactForm .form-control.is-invalid ~ .invalid-feedback {
    display: block;
}