/* ===============================================
   Material 3 Inspired Academic Profile Theme
   =============================================== */

/* Root Variables - Color Palette */
:root {
    /* Material 3 Color Scheme */
    --primary: #0066cc;
    --on-primary: #ffffff;
    --primary-container: #d9e2ff;
    --on-primary-container: #000b57;
    
    --secondary: #5a6b8a;
    --on-secondary: #ffffff;
    --secondary-container: #dfe1f5;
    --on-secondary-container: #131c31;
    
    --tertiary: #7d5260;
    --on-tertiary: #ffffff;
    --tertiary-container: #ffd8e4;
    --on-tertiary-container: #31111d;
    
    --error: #b3261e;
    --on-error: #ffffff;
    --error-container: #f9dedc;
    --on-error-container: #410e0b;
    
    --background: #fffbfe;
    --on-background: #1c1b1f;
    --surface: #fffbfe;
    --on-surface: #1c1b1f;
    --surface-variant: #e7e0ec;
    --on-surface-variant: #49454e;
    
    /* Neutral Colors */
    --neutral-90: #f4eff4;
    --neutral-85: #ede7f1;
    --neutral-80: #e6dce6;
    --neutral-70: #d0c4d0;
    
    /* Shadows and Effects */
    --shadow-1: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-2: 0 3px 6px rgba(0, 0, 0, 0.15);
    --shadow-3: 0 6px 12px rgba(0, 0, 0, 0.18);
    --shadow-4: 0 12px 24px rgba(0, 0, 0, 0.2);
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* Border Radius */
    --radius-xs: 4px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-short: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-standard: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-long: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===============================================
   Global Styles
   =============================================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background-color: var(--background);
    color: var(--on-background);
    line-height: 1.6;
    font-size: 16px;
}

/* ===============================================
   Navigation Bar
   =============================================== */

.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: var(--surface);
    box-shadow: var(--shadow-1);
    transition: box-shadow var(--transition-standard);
}

.navbar:hover {
    box-shadow: var(--shadow-2);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo a {
    display: flex;
    align-items: center;
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition-short);
}

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

.logo-icon {
    margin-right: var(--spacing-sm);
    font-size: 1.5rem;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    background-color: var(--neutral-90);
    padding: var(--spacing-xs);
    border-radius: var(--radius-full);
}

/* Navigation Link Styles - Material 3 Expressive */
.nav-link {
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-full);
    color: var(--on-surface-variant);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    font-size: 0.9375rem;
    transition: all var(--transition-short);
    position: relative;
    overflow: hidden;
}

.nav-link::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(0, 102, 204, 0.08) 0%, rgba(0, 102, 204, 0.02) 100%);
    opacity: 0;
    transition: opacity var(--transition-short);
}

.nav-link:hover {
    color: var(--primary);
    background-color: transparent;
}

.nav-link:hover::before {
    opacity: 1;
}

.nav-link.active {
    background-color: var(--primary);
    color: var(--on-primary);
    box-shadow: 0 2px 4px rgba(0, 102, 204, 0.2);
}

.nav-link.active::before {
    opacity: 0;
}

.nav-link.active:hover {
    background-color: var(--primary);
    color: var(--on-primary);
}

/* ===============================================
   Container & Main Content
   =============================================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

main {
    padding: var(--spacing-3xl) 0;
}

/* ===============================================
   Hero Section
   =============================================== */

.hero-section {
    padding: var(--spacing-3xl) 0;
    animation: fadeInUp 0.6s ease-out;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.profile-image-container {
    display: flex;
    justify-content: center;
    animation: scaleIn 0.8s ease-out;
}

.profile-image-placeholder {
    width: 280px;
    height: 280px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-container) 0%, var(--secondary-container) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 120px;
    color: var(--primary);
    box-shadow: var(--shadow-4);
    position: relative;
    overflow: hidden;
}

.profile-image-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.profile-image-placeholder::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.1) 50%, transparent 70%);
    animation: shimmer 3s infinite;
}

.hero-text {
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-title {
    font-size: 3rem;
    font-weight: var(--font-weight-bold);
    color: var(--on-background);
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.375rem;
    color: var(--primary);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-lg);
}

.hero-description {
    font-size: 1.0625rem;
    color: var(--on-surface-variant);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.social-links {
    display: flex;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background-color: var(--primary-container);
    color: var(--primary);
    transition: all var(--transition-short);
    text-decoration: none;
    font-size: 1.25rem;
}

.social-link img {
    max-width: 100%;
    height: auto;
}

.social-link:hover {
    background-color: var(--primary);
    color: var(--on-primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-3);
}

.social-link:active {
    transform: scale(0.95);
}

/* ===============================================
   WakaTime Badge - Material Design 3 Expressive Style
   =============================================== */

.wakatime-badge-container {
    margin-top: var(--spacing-xl);
    animation: fadeIn 0.6s ease-out;
}

.wakatime-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--surface-variant);
    border-radius: var(--radius-full);
    text-decoration: none;
    transition: all var(--transition-short);
    box-shadow: var(--shadow-1);
    overflow: hidden;
}

.wakatime-badge:hover {
    background-color: var(--primary-container);
    box-shadow: var(--shadow-2);
    transform: translateY(-2px);
}

.wakatime-badge:active {
    transform: scale(0.98);
    box-shadow: var(--shadow-1);
}

.wakatime-badge img {
    height: 28px;
    width: auto;
    display: block;
}

/* ===============================================
   Section Headers
   =============================================== */

.section-header {
    margin-bottom: var(--spacing-2xl);
    animation: fadeIn 0.6s ease-out;
}

.section-header h2 {
    font-size: 2rem;
    font-weight: var(--font-weight-bold);
    color: var(--on-background);
    margin-bottom: var(--spacing-md);
}

.header-line {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: var(--radius-full);
}

/* ===============================================
   About Section
   =============================================== */

.about-section {
    padding: var(--spacing-2xl) 0;
    background-color: var(--neutral-90);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    margin: var(--spacing-3xl) 0;
    animation: fadeInUp 0.6s ease-out;
}

.about-content p {
    font-size: 1.0625rem;
    color: var(--on-surface-variant);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.about-content p:last-child {
    margin-bottom: 0;
}

/* ===============================================
   Interests Section
   =============================================== */

.interests-section {
    padding: var(--spacing-3xl) 0;
    animation: fadeInUp 0.8s ease-out;
}

.interests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-2xl);
}

.interest-card {
    padding: var(--spacing-xl);
    background-color: var(--surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--surface-variant);
    transition: all var(--transition-standard);
    cursor: pointer;
    animation: fadeInUp 0.6s ease-out;
}

.interest-card:nth-child(2) {
    animation-delay: 0.1s;
}

.interest-card:nth-child(3) {
    animation-delay: 0.2s;
}

.interest-card:nth-child(4) {
    animation-delay: 0.3s;
}

.interest-card:hover {
    background-color: var(--primary-container);
    border-color: var(--primary);
    transform: translateY(-8px);
    box-shadow: var(--shadow-3);
}

.interest-icon {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: var(--spacing-lg);
    display: inline-block;
    transition: transform var(--transition-short);
    min-height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.interest-icon img {
    width: 180px;
    height: 180px;
    object-fit: contain;
}

.interest-card:hover .interest-icon {
    transform: scale(1.2) rotate(10deg);
}

.interest-card h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    color: var(--on-background);
    margin-bottom: var(--spacing-md);
}

.interest-card p {
    font-size: 0.9375rem;
    color: var(--on-surface-variant);
    line-height: 1.6;
}

/* ===============================================
   Experience Section
   =============================================== */

.experience-section {
    padding: var(--spacing-3xl) 0;
    animation: fadeInUp 0.8s ease-out;
}

.timeline {
    margin-top: var(--spacing-2xl);
    position: relative;
    padding-left: var(--spacing-xl);
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: var(--radius-full);
}

.timeline-item {
    margin-bottom: var(--spacing-2xl);
    position: relative;
    animation: fadeInUp 0.6s ease-out;
}

.timeline-item:nth-child(2) {
    animation-delay: 0.1s;
}

.timeline-item:nth-child(3) {
    animation-delay: 0.2s;
}

.timeline-marker {
    position: absolute;
    left: -11px;
    top: 0;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--primary);
    border: 3px solid var(--background);
    box-shadow: 0 0 0 2px var(--primary);
    transition: all var(--transition-short);
}

.timeline-item:hover .timeline-marker {
    transform: scale(1.3);
    box-shadow: 0 0 0 2px var(--background), 0 0 0 4px var(--primary);
}

.timeline-content {
    background-color: var(--neutral-90);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    transition: all var(--transition-short);
}

.timeline-item:hover .timeline-content {
    background-color: var(--primary-container);
    box-shadow: var(--shadow-2);
}

.timeline-content h3 {
    font-size: 1.125rem;
    font-weight: var(--font-weight-semibold);
    color: var(--on-background);
    margin-bottom: var(--spacing-xs);
}

.timeline-date {
    color: var(--primary);
    font-weight: var(--font-weight-semibold);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-sm);
}

.timeline-content p {
    color: var(--on-surface-variant);
    font-size: 0.9375rem;
}

/* ===============================================
   Contact Section
   =============================================== */

.contact-section {
    padding: var(--spacing-3xl) var(--spacing-xl);
    background: linear-gradient(135deg, var(--primary-container) 0%, var(--secondary-container) 100%);
    border-radius: var(--radius-lg);
    text-align: center;
    margin: var(--spacing-3xl) 0;
    animation: fadeInUp 0.8s ease-out;
}

.contact-section .section-header {
    text-align: center;
    margin: 0 auto var(--spacing-xl);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.contact-section .header-line {
    width: 60px;
    margin: 0 auto;
}

.contact-section p {
    font-size: 1.0625rem;
    color: var(--on-background);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.cta-button {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-xl);
    background-color: var(--primary);
    color: var(--on-primary);
    text-decoration: none;
    border-radius: var(--radius-full);
    font-weight: var(--font-weight-semibold);
    margin-top: var(--spacing-lg);
    transition: all var(--transition-short);
    box-shadow: var(--shadow-2);
}

.cta-button:hover {
    background-color: var(--on-primary-container);
    transform: translateY(-2px);
    box-shadow: var(--shadow-3);
}

.cta-button:active {
    transform: translateY(0);
    box-shadow: var(--shadow-1);
}

/* ===============================================
   Footer
   =============================================== */

.footer {
    background-color: var(--surface);
    border-top: 1px solid var(--surface-variant);
    padding: var(--spacing-xl) var(--spacing-lg);
    text-align: center;
    color: var(--on-surface-variant);
    font-size: 0.875rem;
}

/* ===============================================
   Projects Section
   =============================================== */

.projects-section {
    padding: var(--spacing-3xl) 0;
    animation: fadeInUp 0.8s ease-out;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-2xl);
    margin-top: var(--spacing-2xl);
}

.project-card {
    background-color: var(--surface);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-2);
    transition: all var(--transition-standard);
    animation: fadeInUp 0.6s ease-out;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.project-card:nth-child(2) {
    animation-delay: 0.1s;
}

.project-card:nth-child(3) {
    animation-delay: 0.2s;
}

.project-card:nth-child(4) {
    animation-delay: 0.3s;
}

.project-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow-4);
}

.project-image-container {
    width: 100%;
    height: 220px;
    background: linear-gradient(135deg, var(--primary-container) 0%, var(--secondary-container) 100%);
    overflow: hidden;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.project-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-standard);
}

.project-card:hover .project-image {
    transform: scale(1.08);
}

.project-image-container.project-placeholder {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
}

.placeholder-icon {
    font-size: 4rem;
    color: var(--on-primary);
    opacity: 0.9;
}

.project-content {
    padding: var(--spacing-lg);
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.project-card h3 {
    font-size: 1.25rem;
    font-weight: var(--font-weight-semibold);
    color: var(--on-background);
    margin-bottom: var(--spacing-sm);
}

.project-description {
    font-size: 0.9375rem;
    color: var(--on-surface-variant);
    line-height: 1.6;
    margin-bottom: var(--spacing-lg);
    flex-grow: 1;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--primary-container);
    color: var(--primary);
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: var(--font-weight-medium);
    transition: all var(--transition-short);
    width: fit-content;
}

.project-link:hover {
    background-color: var(--primary);
    color: var(--on-primary);
    transform: translateX(4px);
}

.project-link:active {
    transform: translateX(2px);
}

/* ===============================================
   Animations
   =============================================== */

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

/* ===============================================
   Responsive Design
   =============================================== */

/* Tablet devices */
@media (max-width: 768px) {
    .nav-container {
        padding: var(--spacing-md);
    }

    .nav-menu {
        gap: var(--spacing-xs);
        padding: var(--spacing-xs);
    }

    .nav-link {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.875rem;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-2xl);
    }

    .profile-image-placeholder {
        width: 200px;
        height: 200px;
        font-size: 80px;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.125rem;
    }

    .interest-card {
        padding: var(--spacing-lg);
    }

    .section-header h2 {
        font-size: 1.5rem;
    }

    .projects-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: var(--spacing-xl);
    }

    main {
        padding: var(--spacing-2xl) 0;
    }
}

/* Mobile devices */
@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }

    .nav-container {
        flex-direction: column;
        gap: var(--spacing-md);
        padding: var(--spacing-md);
    }

    .nav-menu {
        width: 100%;
        justify-content: center;
        flex-wrap: wrap;
        gap: var(--spacing-sm);
        padding: var(--spacing-xs);
    }

    .nav-link {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.875rem;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-subtitle {
        font-size: 0.9375rem;
    }

    .hero-description {
        font-size: 0.9375rem;
    }

    .section-header h2 {
        font-size: 1.25rem;
    }

    .social-links {
        gap: var(--spacing-md);
    }

    .social-link {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }

    .interests-grid {
        grid-template-columns: 1fr;
    }

    .projects-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }

    .timeline {
        padding-left: var(--spacing-lg);
    }

    .timeline::before {
        left: 0;
    }

    .timeline-marker {
        left: -10px;
    }

    .contact-section {
        padding: var(--spacing-xl) var(--spacing-md);
    }

    .cta-button {
        display: block;
        width: 100%;
    }

    main {
        padding: var(--spacing-xl) 0;
    }
}

/* ===============================================
   Accessibility & Print Styles
   =============================================== */

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

@media print {
    .navbar,
    .footer {
        display: none;
    }

    body {
        background-color: white;
    }

    a {
        text-decoration: underline;
    }
}