:root {
    --font-main: 'Outfit', sans-serif;
    --text-color: #E2E8F0;
    --text-muted: #94A3B8;
    --glass-bg: rgba(15, 15, 15, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.5);
    --accent-glow: #ffffff;
}

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

body {
    font-family: var(--font-main);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    background-color: #000000;
}

/* Aurora Background */
.aurora-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    overflow: hidden;
    background: #000000;
}

.aurora-blob {
    display: none;
}

.blob-1 {
    width: 60vw;
    height: 60vw;
    background: #4f46e5;
    /* Indigo */
    top: -10%;
    left: -10%;
    animation-delay: 0s;
}

.blob-2 {
    width: 50vw;
    height: 50vw;
    background: #0ea5e9;
    /* Sky Blue */
    bottom: -10%;
    right: -10%;
    animation-delay: -5s;
}

.blob-3 {
    width: 40vw;
    height: 40vw;
    background: #8b5cf6;
    /* Violet */
    top: 40%;
    left: 40%;
    animation-delay: -10s;
}

@keyframes float {

    0%,
    100% {
        transform: translate(0, 0) scale(1);
    }

    33% {
        transform: translate(30px, -50px) scale(1.1);
    }

    66% {
        transform: translate(-20px, 20px) scale(0.9);
    }
}

/* 3D Container */
#canvas-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
}

/* Glassmorphism Utilities */
.glass-nav,
.glass-card,
.btn-glass {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
}

/* Navigation */
.glass-nav {
    position: fixed;
    top: 2rem;
    left: 0;
    right: 0;
    margin: 0 auto;
    width: 90%;
    max-width: 1100px;
    padding: 1rem 2rem;
    border-radius: 50px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
}

.logo {
    font-weight: 700;
    font-size: 1.5rem;
    letter-spacing: -1px;
    color: #f8fafc;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.mobile-nav {
    display: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

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

/* Mode Toggle */
.mode-toggle {
    margin-left: 2rem;
}

#mode-switch {
    display: none;
}

.toggle-label {
    width: 60px;
    height: 30px;
    background: rgba(25, 25, 25, 0.6);
    border-radius: 30px;
    position: relative;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5px;
    border: 1px solid var(--glass-border);
    transition: background 0.3s;
}

.toggle-ball {
    position: absolute;
    top: 2px;
    left: 2px;
    width: 24px;
    height: 24px;
    background: #e2e8f0;
    border-radius: 50%;
    transition: transform 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.5);
    z-index: 2;
}

.icon-pro,
.icon-fun {
    font-size: 14px;
    z-index: 1;
    user-select: none;
}

#mode-switch:checked+.toggle-label .toggle-ball {
    transform: translateX(30px);
}

#mode-switch:checked+.toggle-label {
    background: rgba(25, 25, 25, 0.8);
}

/* Hero Section */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 1rem;
}

.hero-content {
    max-width: 800px;
}

.hero-name {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-color);
    letter-spacing: 1px;
}

.tagline {
    display: inline-block;
    margin-bottom: 1rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.9rem;
    color: var(--accent-glow);
}

.hero-title {
    font-size: 4.5rem;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    font-weight: 700;
    letter-spacing: -2px;
    color: #f1f5f9;
}

.gradient-text {
    color: var(--accent-glow);
}

.hero-desc {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn-glass {
    display: inline-block;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    color: #fff;
    font-weight: 600;
    transition: transform 0.3s, box-shadow 0.3s;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-glass:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
    background: rgba(255, 255, 255, 0.2);
}

.btn-glass.large {
    font-size: 1.2rem;
    padding: 1.2rem 3rem;
}

/* Sections */
.section {
    padding: 8rem 1rem;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    font-weight: 700;
    letter-spacing: -1px;
    color: #f1f5f9;
}

/* Projects */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    border-radius: 24px;
    padding: 2.5rem;
    transition: transform 0.3s;
    min-height: 300px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
}

.project-card:hover {
    transform: translateY(-10px);
    background: rgba(25, 25, 25, 0.85);
}

.project-cat {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--accent-glow);
    margin-bottom: 0.5rem;
    display: block;
}

.project-card h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: #f8fafc;
}

.project-card p {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.project-link {
    text-decoration: none;
    color: #f1f5f9;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s;
}

.project-link:hover {
    color: var(--accent-glow);
}

/* About */
.about-card {
    padding: 4rem;
    border-radius: 30px;
}

.about-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    align-items: center;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 2rem;
}

.skills-list span {
    background: rgba(255, 255, 255, 0.1);
    padding: 0.5rem 1rem;
    border-radius: 12px;
    font-weight: 500;
    font-size: 0.9rem;
    color: #e2e8f0;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.skills-list span i {
    margin-right: 8px;
}

.skills-list span .fa-python {
    color: #FFD43B;
}

.skills-list span .fa-git-alt {
    color: #F05032;
}

.skills-list span .fa-java {
    color: #5382a1;
}

.skills-list span .fa-raspberry-pi {
    color: #C51A4A;
}

.skills-list span .fa-network-wired {
    color: var(--accent-glow);
}

.profile-photo {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    object-fit: cover;
    display: block;
    margin: 0 auto;
    box-shadow: 0 0 50px rgba(79, 70, 229, 0.3);
    border: 2px solid rgba(255, 255, 255, 0.1);
}

/* Contact */
.contact-card {
    padding: 5rem 2rem;
    border-radius: 30px;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    background: rgba(25, 25, 25, 0.6);
    border: 1px solid var(--glass-border);
}

.contact-card p {
    font-size: 1.2rem;
    color: var(--text-color);
    margin-bottom: 2.5rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.social-links {
    margin-top: 4rem;
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

.social-links a {
    color: #e2e8f0;
    text-decoration: none;
    font-size: 1.5rem;
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.social-links a:hover {
    background: var(--accent-glow);
    transform: translateY(-5px);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.4);
    border-color: var(--accent-glow);
    color: #000000;
}

footer {
    text-align: center;
    padding: 3rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 768px) {
    .theme-btn {
        bottom: auto;
        top: 2rem;
        right: 5%;
        width: 3.4rem;
        height: 3.4rem;
    }
    .hero-title {
        font-size: 3rem;
    }

    .glass-nav {
        width: calc(90% - 3.4rem - 1rem); /* 90% minus button width minus some gap */
        margin-left: 5%;
        margin-right: auto;
        padding: 0 1.2rem;
        height: 3.4rem;
        flex-wrap: nowrap;
        border-radius: 50px;
    }

    .desktop-nav {
        display: none;
    }

    .mobile-nav {
        display: flex;
        position: fixed;
        bottom: 1.5rem;
        left: 50%;
        transform: translateX(-50%);
        width: 90%;
        max-width: 400px;
        background: var(--glass-bg);
        border: 1px solid var(--glass-border);
        box-shadow: 0 10px 30px rgba(0,0,0,0.5);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        padding: 0.8rem 1rem;
        border-radius: 50px;
        justify-content: space-between;
        gap: 0;
        z-index: 1000;
        margin: 0;
    }
    
    .nav-links a {
        font-size: 0.85rem;
        padding: 0.5rem;
        font-weight: 600;
    }

    .mode-toggle {
        margin-left: auto;
    }

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

    .visual-circle {
        width: 200px;
        height: 200px;
    }

    .about-card {
        padding: 2rem;
    }
}

/* Education Roadmap */
.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

/* Education Roadmap - Liquid Glass Theme */
.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem 0;
}

/* Glowing Line */
.timeline::after {
    content: '';
    position: absolute;
    width: 2px;
    background: linear-gradient(to bottom,
            rgba(255, 255, 255, 0),
            rgba(255, 255, 255, 0.5),
            rgba(255, 255, 255, 0));
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -1px;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.4);
}

.timeline-item {
    padding: 20px 50px;
    position: relative;
    width: 50%;
    box-sizing: border-box;
}

.timeline-item.left {
    left: 0;
}

.timeline-item.right {
    left: 50%;
}

/* Glowing Orbs */
.timeline-item::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    right: -8px;
    background: #000000;
    border: 2px solid var(--accent-glow);
    top: 28px;
    border-radius: 50%;
    z-index: 2;
    box-shadow: 0 0 15px var(--accent-glow), inset 0 0 10px var(--accent-glow);
    transition: transform 0.3s ease;
}

.timeline-item.right::after {
    left: -8px;
}

.timeline-item:hover::after {
    transform: scale(1.3);
    background: var(--accent-glow);
    box-shadow: 0 0 25px var(--accent-glow);
}

/* Glass Cards */
.timeline-content {
    padding: 1.5rem 2rem;
    border-radius: 20px;
    position: relative;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    background: rgba(25, 25, 25, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
}

.timeline-content:hover {
    transform: translateY(-8px) scale(1.02);
    background: rgba(25, 25, 25, 0.7);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.5),
        0 0 20px rgba(255, 255, 255, 0.1);
}

/* Date Badge */
.timeline-content .date {
    display: inline-block;
    margin-bottom: 1rem;
    padding: 0.4rem 1rem;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    font-size: 0.85rem;
    color: var(--accent-glow);
    font-weight: 600;
    letter-spacing: 0.5px;
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.1);
}

.timeline-content h3 {
    margin-bottom: 0.5rem;
    color: #f1f5f9;
    font-size: 1.4rem;
    font-weight: 700;
}

.timeline-content h4 {
    margin-bottom: 1rem;
    color: #94a3b8;
    font-weight: 500;
    font-size: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Add an icon before the institution name if desired */
.timeline-content h4::before {
    content: '🏫';
    /* Fallback icon */
    font-size: 0.9em;
    filter: grayscale(1);
    opacity: 0.7;
}

.timeline-content p {
    color: #cbd5e1;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Responsive Timeline */
@media screen and (max-width: 768px) {
    .timeline::after {
        left: 20px;
    }

    .timeline-item {
        width: 100%;
        padding-left: 50px;
        padding-right: 20px;
        margin-bottom: 1rem;
    }

    .timeline-item.left,
    .timeline-item.right {
        left: 0;
    }

    .timeline-item::after {
        left: 12px;
        right: auto;
    }

    .timeline-item.right::after {
        left: 12px;
    }
}

/* Theme Toggle Button */
.theme-btn {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
    color: var(--text-color);
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-btn:hover {
    transform: rotate(15deg) scale(1.1);
    box-shadow: 0 0 20px var(--accent-glow);
    color: var(--accent-glow);
}

/* Light Theme Overrides */
body.light-theme {
    --text-color: #1e293b;
    --text-muted: #64748b;
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.1);
    --accent-glow: #000000;
    background-color: #f8fafc;
}

body.light-theme .aurora-bg {
    background: #f8fafc;
}

body.light-theme .project-card:hover {
    background: rgba(255, 255, 255, 0.9);
}

body.light-theme .social-links a {
    color: #1e293b;
    border-color: rgba(0, 0, 0, 0.1);
}

body.light-theme .timeline::after {
    background: linear-gradient(to bottom,
            rgba(0, 0, 0, 0),
            rgba(0, 0, 0, 0.5),
            rgba(0, 0, 0, 0));
    box-shadow: none;
}

body.light-theme .timeline-item::after {
    background: #ffffff;
}

body.light-theme .hero-title,
body.light-theme .section-title,
body.light-theme h3 {
    color: #1e293b;
}

body.light-theme .timeline-content h4 {
    color: #64748b;
}

body.light-theme p {
    color: #334155;
}

body.light-theme .project-link {
    color: #000000;
}

body.light-theme .logo {
    color: #1e293b;
}

body.light-theme .contact-card {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(255, 255, 255, 0.5);
}

body.light-theme .timeline-content {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(255, 255, 255, 0.5);
}

body.light-theme .timeline-content:hover {
    background: rgba(255, 255, 255, 0.9);
    border-color: rgba(0, 0, 0, 0.3);
    box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.2);
}

body.light-theme .btn-glass {
    color: #ffffff;
    background: #000000;
    border-color: #000000;
}

body.light-theme .btn-glass:hover {
    background: rgba(0, 0, 0, 0.8);
    color: #ffffff;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.2);
}

body.light-theme .skills-list span {
    color: #1e293b;
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(0, 0, 0, 0.2);
}

/* ─── Activity Section: Tabs & Shared ─────────────────────────── */
.activity-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    position: relative;
    background: rgba(30, 41, 59, 0.5);
    border-radius: 50px;
    padding: 5px;
    width: fit-content;
    border: 1px solid rgba(255, 255, 255, 0.08);
}

.activity-tab {
    position: relative;
    z-index: 2;
    padding: 0.7rem 1.8rem;
    border: none;
    border-radius: 50px;
    background: transparent;
    color: var(--text-muted);
    font-family: var(--font-main);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: color 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.activity-tab:hover {
    color: var(--text-color);
}

.activity-tab.active {
    color: #fff;
}

.activity-tab i {
    font-size: 1.1rem;
}

.tab-indicator {
    position: absolute;
    bottom: 5px;
    top: 5px;
    left: 5px;
    border-radius: 50px;
    background: rgba(56, 189, 248, 0.25);
    border: 1px solid rgba(56, 189, 248, 0.3);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.15);
    transition: left 0.35s cubic-bezier(0.4, 0, 0.2, 1),
                width 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 1;
}

/* Tab Panes */
.activity-pane {
    display: none !important;
    opacity: 0;
    transform: translateY(15px);
    transition: opacity 0.4s ease, transform 0.4s ease;
}

.activity-pane.active {
    display: block !important;
    opacity: 1;
    transform: translateY(0);
}

/* Shared Activity Card */
.activity-card {
    padding: 2.5rem;
    border-radius: 24px;
    overflow: hidden;
}

.activity-profile-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.activity-profile-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.activity-profile-link i {
    font-size: 1.5rem;
    color: var(--text-color);
}

.activity-profile-link a {
    color: var(--accent-glow);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: opacity 0.3s;
}

.activity-profile-link a:hover {
    opacity: 0.8;
    text-decoration: underline;
}

/* ─── Shared Heatmap Styles ───────────────────────────────────── */

/* Stats Bar */
.heatmap-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
}

.heatmap-stat {
    text-align: center;
    padding: 1rem 0.5rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: all 0.3s ease;
}

.heatmap-stat:hover {
    background: rgba(56, 189, 248, 0.05);
    border-color: rgba(56, 189, 248, 0.15);
    transform: translateY(-2px);
}

.stat-value {
    display: block;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent-glow);
    line-height: 1.2;
    margin-bottom: 0.25rem;
}

.stat-label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 500;
}

/* Heatmap Graph */
.heatmap-graph-wrapper {
    overflow-x: auto;
    overflow-y: hidden;
    padding: 0.5rem 0;
    scrollbar-width: thin;
    scrollbar-color: rgba(56, 189, 248, 0.3) transparent;
}

.heatmap-graph-wrapper::-webkit-scrollbar {
    height: 6px;
}

.heatmap-graph-wrapper::-webkit-scrollbar-track {
    background: transparent;
}

.heatmap-graph-wrapper::-webkit-scrollbar-thumb {
    background: rgba(56, 189, 248, 0.3);
    border-radius: 3px;
}

.heatmap-svg {
    display: block;
    min-width: 100%;
}

.heatmap-cell {
    cursor: pointer;
    transition: opacity 0.15s ease, transform 0.15s ease;
    outline: none;
}

.heatmap-cell:hover {
    opacity: 0.85;
    stroke: rgba(255, 255, 255, 0.3);
    stroke-width: 1.5;
}

.heatmap-month-label {
    fill: var(--text-muted);
    font-size: 10px;
    font-family: var(--font-main);
    font-weight: 500;
}

.heatmap-day-label {
    fill: var(--text-muted);
    font-size: 10px;
    font-family: var(--font-main);
    font-weight: 500;
}

/* Legend */
.heatmap-legend {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 4px;
    margin-top: 1rem;
    padding-top: 1rem;
}

.legend-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin: 0 6px;
    font-weight: 500;
}

.legend-cell {
    display: inline-block;
    width: 13px;
    height: 13px;
    border-radius: 3px;
}

/* Tooltip */
.heatmap-tooltip {
    position: absolute;
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: #e2e8f0;
    padding: 8px 12px;
    border-radius: 10px;
    font-size: 0.8rem;
    pointer-events: none;
    z-index: 10000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
    border: 1px solid rgba(56, 189, 248, 0.2);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    white-space: nowrap;
    line-height: 1.5;
}

.heatmap-tooltip strong {
    color: var(--accent-glow);
}

/* Loading State */
.heatmap-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem;
    gap: 1rem;
}

.heatmap-loading p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.loading-pulse {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--accent-glow);
    animation: pulse-glow 1.5s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% {
        transform: scale(0.8);
        opacity: 0.4;
        box-shadow: 0 0 0 0 rgba(56, 189, 248, 0.4);
    }
    50% {
        transform: scale(1);
        opacity: 1;
        box-shadow: 0 0 20px 10px rgba(56, 189, 248, 0.1);
    }
}

/* Error State */
.heatmap-error {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem;
    gap: 0.5rem;
}

.heatmap-error p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.heatmap-fallback-link {
    margin-top: 1rem;
    color: var(--accent-glow);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.5rem;
    background: rgba(56, 189, 248, 0.1);
    border-radius: 50px;
    border: 1px solid rgba(56, 189, 248, 0.2);
    transition: all 0.3s ease;
}

.heatmap-fallback-link:hover {
    background: rgba(56, 189, 248, 0.2);
    transform: translateY(-2px);
}

/* ─── LeetCode Specific ──────────────────────────────────────── */
.lc-accent {
    color: #FFA116 !important;
}

.lc-stats-grid {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 2.5rem;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

/* Circular Progress Ring */
.lc-total-ring {
    position: relative;
    width: 130px;
    height: 130px;
}

.ring-svg {
    width: 100%;
    height: 100%;
    transform: rotate(0deg);
}

.ring-progress {
    transition: stroke-dasharray 1.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.ring-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.ring-value {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-color);
    line-height: 1;
}

.ring-label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 4px;
}

/* Difficulty Bars */
.lc-difficulty-bars {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.diff-row {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

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

.diff-badge {
    padding: 0.2rem 0.75rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.diff-count {
    font-weight: 600;
    color: var(--text-color);
    font-size: 0.95rem;
}

.diff-total {
    color: var(--text-muted);
    font-weight: 400;
    font-size: 0.85rem;
}

.diff-bar-track {
    width: 100%;
    height: 8px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: 10px;
    overflow: hidden;
}

.diff-bar-fill {
    height: 100%;
    border-radius: 10px;
    transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 8px rgba(255, 255, 255, 0.1);
}

/* Mini Stats for LeetCode */
.lc-mini-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
}

/* ─── Light Theme: Activity Section ───────────────────────────── */
body.light-theme .activity-tabs {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(14, 165, 233, 0.15);
}

body.light-theme .activity-tab {
    color: #64748b;
}

body.light-theme .activity-tab:hover {
    color: #1e293b;
}

body.light-theme .activity-tab.active {
    color: #0f172a;
}

body.light-theme .tab-indicator {
    background: rgba(14, 165, 233, 0.15);
    border-color: rgba(14, 165, 233, 0.3);
    box-shadow: 0 0 10px rgba(14, 165, 233, 0.1);
}

body.light-theme .activity-card {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(255, 255, 255, 0.5);
}

body.light-theme .heatmap-stat {
    background: rgba(14, 165, 233, 0.04);
    border-color: rgba(14, 165, 233, 0.1);
}

body.light-theme .heatmap-stat:hover {
    background: rgba(14, 165, 233, 0.08);
    border-color: rgba(14, 165, 233, 0.2);
}

body.light-theme .heatmap-tooltip {
    background: rgba(255, 255, 255, 0.95);
    color: #1e293b;
    border-color: rgba(14, 165, 233, 0.3);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

body.light-theme .heatmap-cell:hover {
    stroke: rgba(0, 0, 0, 0.15);
}

body.light-theme .heatmap-fallback-link {
    color: #0ea5e9;
    background: rgba(14, 165, 233, 0.1);
    border-color: rgba(14, 165, 233, 0.3);
}

body.light-theme .lc-stats-grid {
    border-bottom-color: rgba(0, 0, 0, 0.06);
}

body.light-theme .diff-bar-track {
    background: rgba(0, 0, 0, 0.06);
}

body.light-theme .ring-svg circle:first-child {
    stroke: rgba(0, 0, 0, 0.06);
}

/* ─── Responsive: Activity Section ────────────────────────────── */
@media (max-width: 768px) {
    .activity-card {
        padding: 1.5rem;
    }

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

    .stat-value {
        font-size: 1.4rem;
    }

    .lc-stats-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .lc-total-ring {
        width: 110px;
        height: 110px;
        margin: 0 auto;
    }

    .ring-value {
        font-size: 1.6rem;
    }
}