/* ===========================================
   ELEVATED MINIMAL — Design System
   Inspired by Vercel, Linear, Raycast
   Target: Recruiters, HR, Developers
   =========================================== */

:root {
    --bg-color: #FAFBFC;
    --bg-secondary: #F1F5F9;
    --text-color: #0f172a;
    --text-muted: #64748b;
    --accent-color: #2563EB;
    --accent-light: #3b82f6;
    --accent-bg: rgba(37, 99, 235, 0.08);
    --accent-border: rgba(37, 99, 235, 0.2);
    --glass-bg: rgba(250, 251, 252, 0.8);
    --glass-border: rgba(0, 0, 0, 0.06);
    --timeline-color: rgba(37, 99, 235, 0.2);
    --timeline-dot-bg: #FAFBFC;
    --input-bg: #f8fafc;
    --card-bg: #FFFFFF;
    --card-border: rgba(0, 0, 0, 0.04);
    --card-shadow:
        0 0 0 1px rgba(0,0,0,0.03),
        0 2px 4px rgba(0,0,0,0.02),
        0 12px 28px rgba(0,0,0,0.04);
    --card-shadow-hover:
        0 0 0 1px rgba(37,99,235,0.08),
        0 4px 8px rgba(0,0,0,0.03),
        0 24px 48px rgba(0,0,0,0.06);
    --card-radius: 1rem;
    --section-radius: 1.25rem;
    --transition: all 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
    --gradient-accent: linear-gradient(135deg, #2563EB, #06b6d4, #8b5cf6);
}

[data-theme="dark"] {
    --bg-color: #0B1120;
    --bg-secondary: #111827;
    --text-color: #f1f5f9;
    --text-muted: #94a3b8;
    --accent-color: #60a5fa;
    --accent-light: #93c5fd;
    --accent-bg: rgba(96, 165, 250, 0.1);
    --accent-border: rgba(96, 165, 250, 0.25);
    --glass-bg: rgba(11, 17, 32, 0.85);
    --glass-border: rgba(255, 255, 255, 0.06);
    --timeline-color: rgba(96, 165, 250, 0.25);
    --timeline-dot-bg: #111827;
    --input-bg: #111827;
    --card-bg: #151F32;
    --card-border: rgba(255, 255, 255, 0.04);
    --card-shadow:
        0 0 0 1px rgba(255,255,255,0.04),
        0 2px 4px rgba(0,0,0,0.15),
        0 12px 28px rgba(0,0,0,0.2);
    --card-shadow-hover:
        0 0 0 1px rgba(96,165,250,0.1),
        0 4px 8px rgba(0,0,0,0.15),
        0 24px 48px rgba(0,0,0,0.25),
        0 0 60px rgba(96,165,250,0.04);
    --gradient-accent: linear-gradient(135deg, #60a5fa, #22d3ee, #a78bfa);
}

/* ===========================================
   BASE
   =========================================== */

* { box-sizing: border-box; }

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* ===========================================
   SCROLL PROGRESS
   =========================================== */

.scroll-progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 2px;
    width: 0%;
    background: var(--gradient-accent);
    z-index: 1001;
    transition: width 0.1s ease-out;
}

/* ===========================================
   NEURAL NET CANVAS
   =========================================== */

#neural-net-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -10;
    opacity: 0.6;
}

/* ===========================================
   NAVBAR — Glassmorphism (only place we use it)
   =========================================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(1.2);
    -webkit-backdrop-filter: blur(20px) saturate(1.2);
    border-bottom: 1px solid var(--glass-border);
    transition: var(--transition);
}
.navbar.scrolled {
    box-shadow: 0 1px 0 var(--glass-border), 0 8px 24px rgba(0,0,0,0.08);
}

.nav-link-top {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
    transition: color 0.2s ease;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}
.nav-link-top:hover,
.nav-link-top.active {
    color: var(--accent-color);
}

/* Mobile menu */
.mobile-menu {
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(1.2);
    -webkit-backdrop-filter: blur(20px) saturate(1.2);
    border-bottom: 1px solid var(--glass-border);
    padding: 1rem;
}
.mobile-menu-link {
    display: block;
    padding: 0.75rem 1rem;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    border-radius: 0.75rem;
    transition: all 0.2s ease;
}
.mobile-menu-link:hover {
    color: var(--accent-color);
    background: var(--accent-bg);
}

/* Theme toggle */
.theme-toggle {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
    border-radius: 50%;
    width: 2.5rem;
    height: 2.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-color);
}
.theme-toggle:hover {
    background: var(--accent-bg);
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    transform: rotate(15deg);
}

/* ===========================================
   TYPOGRAPHY
   =========================================== */

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

/* Section headings — Bold left-bar accent */
.section-heading {
    font-size: 1.5rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--text-color);
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
}
.section-heading::before {
    content: '';
    width: 4px;
    height: 1.5em;
    background: var(--gradient-accent);
    border-radius: 2px;
    flex-shrink: 0;
}
.section-heading::after {
    display: none;
}

/* ===========================================
   BUTTONS — Refined Clay/Elevated
   =========================================== */

.btn-primary {
    display: inline-flex;
    align-items: center;
    padding: 0.75rem 1.75rem;
    background: var(--accent-color);
    color: white;
    font-weight: 700;
    font-size: 0.8rem;
    border-radius: 9999px;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    border: none;
    position: relative;
    box-shadow:
        0 1px 2px rgba(0,0,0,0.1),
        0 4px 12px rgba(37,99,235,0.25);
    cursor: pointer;
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow:
        0 2px 4px rgba(0,0,0,0.1),
        0 12px 28px rgba(37,99,235,0.3);
    background: var(--accent-light);
}
.btn-primary:active {
    transform: translateY(0);
    box-shadow: 0 1px 4px rgba(37,99,235,0.2);
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    padding: 0.75rem 1.75rem;
    background: var(--card-bg);
    color: var(--text-color);
    font-weight: 700;
    font-size: 0.8rem;
    border: 1px solid var(--glass-border);
    border-radius: 9999px;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    cursor: pointer;
}
.btn-secondary:hover {
    border-color: var(--accent-border);
    color: var(--accent-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0,0,0,0.06);
}
.btn-secondary:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(0,0,0,0.04);
}

/* ===========================================
   SOCIAL LINKS
   =========================================== */

.social-link {
    transition: var(--transition);
    opacity: 0.6;
}
.social-link:hover {
    color: var(--accent-color);
    opacity: 1;
    transform: translateY(-2px);
}

/* ===========================================
   CARDS — Elevated Minimal (the core of the design)
   =========================================== */

.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    box-shadow: var(--card-shadow);
    border-radius: var(--card-radius);
    transition: var(--transition);
}
.card:hover {
    box-shadow: var(--card-shadow-hover);
    transform: translateY(-3px);
}

/* Glassmorphism — NAVBAR/OVERLAY ONLY */
.glassmorphism {
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(1.2);
    -webkit-backdrop-filter: blur(20px) saturate(1.2);
    border: 1px solid var(--glass-border);
    transition: var(--transition);
}
.glassmorphism:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    border-color: var(--accent-border);
}

/* ===========================================
   PROJECT CARDS
   =========================================== */

.project-card {
    position: relative;
    overflow: hidden;
}
.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-accent);
    opacity: 0;
    transition: opacity 0.3s ease;
}
.project-card:hover::before {
    opacity: 1;
}

/* ===========================================
   TAGS
   =========================================== */

.tag {
    background-color: var(--accent-bg);
    border: 1px solid transparent;
    color: var(--accent-color);
    font-weight: 600;
    transition: var(--transition);
    cursor: default;
}
.tag:hover {
    background-color: var(--accent-color);
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37,99,235,0.2);
}

/* ===========================================
   TIMELINE
   =========================================== */

.timeline { position: relative; }
.timeline::before {
    content: '';
    position: absolute;
    top: 10px;
    left: 10px;
    bottom: 10px;
    width: 2px;
    background: linear-gradient(to bottom, var(--accent-color), transparent);
    opacity: 0.3;
}
.timeline-item::before {
    content: '';
    position: absolute;
    left: 1px;
    top: 10px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--timeline-dot-bg);
    border: 2px solid var(--accent-color);
    z-index: 1;
}

/* ===========================================
   SCROLL ANIMATIONS
   =========================================== */

.scroll-target {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s cubic-bezier(0.25, 0.8, 0.25, 1), transform 0.7s cubic-bezier(0.25, 0.8, 0.25, 1);
}
.scroll-target.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===========================================
   TYPING CURSOR
   =========================================== */

.typing-cursor {
    display: inline-block;
    width: 3px;
    height: 1.2em;
    background-color: var(--accent-color);
    animation: blink 0.8s infinite;
    vertical-align: middle;
    margin-left: 2px;
    border-radius: 2px;
}
@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0; }
}

/* ===========================================
   SKILL LEVELS — Refined badges
   =========================================== */

.skill-item {
    padding: 0.625rem 0;
    border-bottom: 1px solid var(--glass-border);
}
.skill-item:last-child {
    border-bottom: none;
}
.skill-level {
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 0.3rem 0.75rem;
    border-radius: 0.5rem;
    white-space: nowrap;
}
.skill-level-expert {
    background: var(--accent-color);
    color: white;
    box-shadow: 0 2px 8px rgba(37,99,235,0.2);
}
.skill-level-advanced {
    background: var(--accent-bg);
    color: var(--accent-color);
    border: 1px solid var(--accent-border);
}
.skill-level-intermediate {
    background: var(--bg-secondary);
    color: var(--text-muted);
    border: 1px solid var(--glass-border);
}

/* ===========================================
   CONTACT ITEMS — With tooltip
   =========================================== */

.contact-item {
    transition: var(--transition);
    position: relative;
    border-radius: 0.75rem;
}
.contact-item:hover {
    background: var(--accent-bg);
    transform: translateY(-2px);
}
.contact-item[data-tooltip]:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    background: var(--card-bg);
    color: var(--text-color);
    border: 1px solid var(--card-border);
    box-shadow: 0 4px 20px rgba(0,0,0,0.12);
    padding: 0.5rem 0.75rem;
    border-radius: 0.5rem;
    font-size: 0.75rem;
    white-space: nowrap;
    z-index: 100;
    pointer-events: none;
}
.contact-item[data-tooltip]:hover::before {
    content: '';
    position: absolute;
    bottom: calc(100% + 2px);
    left: 50%;
    transform: translateX(-50%);
    border: 6px solid transparent;
    border-top-color: var(--card-border);
    z-index: 100;
    pointer-events: none;
}

/* ===========================================
   FORM INPUTS
   =========================================== */

.form-input {
    background: var(--input-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-color);
    font-family: 'Inter', sans-serif;
    transition: var(--transition);
    border-radius: 0.75rem;
}
.form-input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px var(--accent-bg);
}

/* ===========================================
   BACK TO TOP
   =========================================== */

.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: var(--card-radius);
    width: 2.75rem;
    height: 2.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    z-index: 50;
    box-shadow: 0 4px 12px rgba(37,99,235,0.25);
}
.back-to-top:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(37,99,235,0.3);
}

/* ===========================================
   UTILITIES
   =========================================== */

.accent-color { color: var(--accent-color); }

/* ===========================================
   PROJECT FILTERS
   =========================================== */

.filter-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 0.4rem 0.9rem;
    border-radius: 0.5rem;
    font-size: 0.75rem;
    font-weight: 600;
    border: 1px solid var(--glass-border);
    background: var(--card-bg);
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}
.filter-btn:hover,
.filter-btn.active {
    background: var(--accent-bg);
    border-color: var(--accent-border);
    color: var(--accent-color);
}

.lang-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    display: inline-block;
    flex-shrink: 0;
}

/* Card "View on GitHub" action */
.card-action {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--accent-color);
    border: 1px solid var(--accent-border);
    border-radius: 0.5rem;
    padding: 0.375rem 0.75rem;
    transition: var(--transition);
    background: transparent;
    margin-top: 0.75rem;
    align-self: flex-start;
}
.project-card:hover .card-action {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.project-card-wrap.hidden-card {
    display: none !important;
}

/* AI/ML term highlighting */
.tech-highlight {
    color: var(--accent-color);
    font-weight: 600;
    background: var(--accent-bg);
    padding: 0 3px;
    border-radius: 3px;
    white-space: nowrap;
}

/* Project loading skeleton */
.project-card-skeleton {
    min-height: 200px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: var(--card-radius);
    padding: 1.5rem;
    overflow: hidden;
    position: relative;
}
.project-card-skeleton::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, transparent 0%, var(--accent-bg) 50%, transparent 100%);
    background-size: 200% 100%;
    animation: skeleton-shimmer 1.5s infinite;
}
@keyframes skeleton-shimmer {
    0%   { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* ===========================================
   RESPONSIVE
   =========================================== */

@media (max-width: 768px) {
    .section-heading { font-size: 1.15rem; }
}