/* ===== CSS Custom Properties ===== */
:root {
    /* Light theme colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-tertiary: #94a3b8;
    --accent: #0077b5;
    --accent-hover: #005a8c;
    --border: #e2e8f0;
    --card-bg: #ffffff;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --card-shadow-hover: 0 10px 40px rgba(0, 0, 0, 0.1);

    /* Spacing */
    --container-width: 800px;
    --section-gap: 4rem;

    /* Transitions */
    --transition: 0.2s ease;
}

[data-theme="dark"] {
    --bg-primary: #0a0a0b;
    --bg-secondary: #111113;
    --bg-tertiary: #1a1a1d;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-tertiary: #64748b;
    --accent: #38bdf8;
    --accent-hover: #7dd3fc;
    --border: #27272a;
    --card-bg: #18181b;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    --card-shadow-hover: 0 10px 40px rgba(0, 0, 0, 0.4);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition), color var(--transition);
}

.is-hidden {
    display: none !important;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ===== Navbar ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    backdrop-filter: blur(10px);
    background: rgba(var(--bg-primary), 0.9);
}

.nav-container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-text {
    color: var(--text-primary);
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-link {
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: color var(--transition);
}

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

.theme-toggle {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    color: var(--text-secondary);
    font-size: 1.1rem;
    transition: color var(--transition);
}

.theme-toggle:hover {
    color: var(--text-primary);
}

/* ===== Main Content ===== */
.main-content {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 6rem 1.5rem 2rem;
}

/* ===== Hero Section ===== */
.hero {
    padding: 3rem 0;
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 3rem;
}

.hero-text {
    flex: 1;
}

.greeting {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.intro {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    max-width: 500px;
}

.hero-actions {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all var(--transition);
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--text-primary);
    color: var(--bg-primary);
}

.btn-primary:hover {
    opacity: 0.85;
    transform: translateY(-1px);
}

.social-links {
    display: flex;
    gap: 0.75rem;
}

.social-link {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-size: 1.1rem;
    transition: all var(--transition);
}

.social-link:hover {
    background: var(--text-primary);
    color: var(--bg-primary);
    transform: translateY(-2px);
}

.hero-image {
    flex-shrink: 0;
}

.profile-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--border);
}

/* ===== Section Styles ===== */
.section {
    padding: var(--section-gap) 0;
}

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

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.view-more {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--accent);
    transition: color var(--transition);
}

.view-more:hover {
    color: var(--accent-hover);
}

/* ===== Tabs ===== */
.tabs {
    display: flex;
    gap: 0.25rem;
    background: var(--bg-tertiary);
    padding: 0.25rem;
    border-radius: 8px;
}

.tab {
    padding: 0.5rem 1rem;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: 6px;
    transition: all var(--transition);
}

.tab.active {
    background: var(--card-bg);
    color: var(--text-primary);
    box-shadow: var(--card-shadow);
}

.tab:hover:not(.active) {
    color: var(--text-primary);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* ===== Experience Cards ===== */
.experience-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: box-shadow var(--transition), transform var(--transition);
}

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

.experience-header {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.company-logo {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    overflow: hidden;
}

.logo-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    background: #ffffff;
    padding: 4px;
}

.logo-letter {
    color: white;
    font-weight: 700;
    font-size: 1.25rem;
}

.experience-info {
    flex: 1;
}

.experience-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.company-name {
    font-size: 0.9rem;
    color: var(--accent);
    transition: color var(--transition);
}

.company-name:hover {
    color: var(--accent-hover);
}

.experience-meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: 0.5rem;
}

.period {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

.type-badge {
    font-size: 0.75rem;
    padding: 0.2rem 0.6rem;
    background: var(--bg-tertiary);
    border-radius: 4px;
    color: var(--text-secondary);
}

.experience-description {
    margin: 0;
    padding-left: 1.25rem;
}

.experience-description li {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.education-description {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== Certifications ===== */
.certifications-grid {
    display: grid;
    gap: 1rem;
}

.certification-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem;
    transition: box-shadow var(--transition), transform var(--transition);
}

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

.cert-icon {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: linear-gradient(135deg, #f59e0b, #d97706);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.cert-icon i {
    color: white;
    font-size: 1.25rem;
}

.cert-info {
    flex: 1;
}

.cert-name {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.cert-issuer {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

.cert-date {
    font-size: 0.8rem;
    color: var(--text-tertiary);
}

.cert-link {
    color: var(--text-tertiary);
    font-size: 0.9rem;
    padding: 0.5rem;
    transition: color var(--transition);
}

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

/* ===== Skills ===== */
.skills-container {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-tag {
    padding: 0.5rem 1rem;
    background: var(--bg-tertiary);
    border-radius: 6px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    transition: all var(--transition);
}

.skill-tag:hover {
    background: var(--text-primary);
    color: var(--bg-primary);
}

/* ===== Projects Grid ===== */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.project-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}

.project-card:hover {
    box-shadow: var(--card-shadow-hover);
    transform: translateY(-3px);
    border-color: var(--accent);
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.75rem;
}

.project-name {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.project-links {
    color: var(--text-tertiary);
    display: flex;
    gap: 0.5rem;
}

.project-links .demo-link,
.project-links .github-link {
    color: var(--text-tertiary);
    padding: 0.25rem;
    transition: color var(--transition);
}

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

.project-links .github-link:hover {
    color: var(--text-primary);
}

.project-card-body {
    display: block;
    color: inherit;
    text-decoration: none;
}

.project-description {
    font-size: 0.85rem;
    color: var(--text-secondary);
    flex: 1;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.project-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.project-stats {
    display: flex;
    gap: 0.75rem;
}

.stat {
    font-size: 0.8rem;
    color: var(--text-tertiary);
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.project-tags {
    display: flex;
    gap: 0.4rem;
}

.tag {
    font-size: 0.7rem;
    padding: 0.25rem 0.5rem;
    background: var(--bg-tertiary);
    border-radius: 4px;
    color: var(--text-tertiary);
}

.language-tag {
    background: rgba(0, 119, 181, 0.1);
    color: var(--accent);
}

/* ===== Footer ===== */
.footer {
    border-top: 1px solid var(--border);
    padding: 2rem 0;
    margin-top: 2rem;
}

.footer-container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.footer-links {
    display: flex;
    gap: 1rem;
}

.footer-links a {
    color: var(--text-tertiary);
    font-size: 1.25rem;
    transition: color var(--transition);
}

.footer-links a:hover {
    color: var(--text-primary);
}

.footer-text {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero,
.section {
    animation: fadeInUp 0.6s ease;
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero-content {
        flex-direction: column-reverse;
        text-align: center;
    }

    .greeting {
        font-size: 1.75rem;
    }

    .intro {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        flex-direction: column;
    }

    .profile-photo {
        width: 120px;
        height: 120px;
    }

    .section-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }

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

/* ===== Competitions ===== */
.competitions-grid {
    display: grid;
    gap: 1.5rem;
}

.competition-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    transition: box-shadow var(--transition), transform var(--transition);
}

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

.competition-header {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1rem;
}

.comp-icon-wrapper {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: var(--bg-tertiary);
    /* Default background if no image */
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    overflow: hidden;
}

.comp-icon-placeholder {
    color: var(--accent);
    font-size: 1.2rem;
}

.comp-header-info {
    flex: 1;
}

.comp-name {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.2rem;
}

.comp-organizer {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.comp-link {
    color: var(--text-tertiary);
    font-size: 1rem;
    padding: 0.5rem;
    transition: color var(--transition);
}

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

.comp-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    padding-left: calc(48px + 1rem);
    /* Align with text */
}

.award-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: rgba(245, 158, 11, 0.1);
    /* Amber tint */
    color: #d97706;
    /* Amber-600 */
    padding: 0.25rem 0.75rem;
    border-radius: 99px;
    font-size: 0.85rem;
    font-weight: 500;
}

[data-theme="dark"] .award-badge {
    background: rgba(251, 191, 36, 0.1);
    color: #fbbf24;
    /* Amber-400 */
}

.comp-date {
    font-size: 0.85rem;
    color: var(--text-tertiary);
}

.comp-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1rem;
    padding-left: calc(48px + 1rem);
    line-height: 1.6;
}

.comp-image-container {
    padding-left: calc(48px + 1rem);
    margin-top: 1rem;
}

.comp-featured-image {
    width: 100%;
    max-height: 350px;
    object-fit: cover;
    border-radius: 8px;
    border: 1px solid var(--border);
}

@media (max-width: 640px) {

    .comp-meta,
    .comp-description,
    .comp-image-container {
        padding-left: 0;
    }

    .competition-header {
        align-items: center;
    }
}

/* ===== Proposal Viewer ===== */
.comp-proposal {
    margin-top: 1rem;
    padding-left: calc(48px + 1rem);
}

.proposal-toggle {
    cursor: pointer;
    font-size: 0.95rem;
    color: var(--accent);
    font-weight: 500;
    transition: color var(--transition);
    list-style: none;
    /* Hide default triangle */
}

.proposal-toggle::-webkit-details-marker {
    display: none;
}

.proposal-toggle:hover {
    color: var(--accent-hover);
}

.proposal-toggle i {
    margin-right: 0.5rem;
}

.proposal-content {
    margin-top: 1rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    background: var(--bg-tertiary);
}

.proposal-frame {
    width: 100%;
    height: 500px;
    border: none;
    display: block;
}

@media (max-width: 640px) {
    .comp-proposal {
        padding-left: 0;
    }

    .proposal-frame {
        height: 350px;
    }
}

/* ===== Hamburger Menu ===== */
.hamburger {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 24px;
    height: 20px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 110;
}

.hamburger span {
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
    transform-origin: center;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-links {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--bg-primary);
        border-bottom: 1px solid var(--border);
        padding: 1rem;
        gap: 0.5rem;
        display: none;
        box-shadow: var(--card-shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links .nav-link {
        padding: 0.75rem 1rem;
        border-radius: 8px;
        transition: background var(--transition);
    }

    .nav-links .nav-link:hover {
        background: var(--bg-tertiary);
    }
}

/* ===== Back to Top Button ===== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
    z-index: 90;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

/* ===== Typing Animation ===== */
.greeting.typing::after {
    content: '|';
    animation: blink 0.7s infinite;
    color: var(--accent);
}

@keyframes blink {

    0%,
    50% {
        opacity: 1;
    }

    51%,
    100% {
        opacity: 0;
    }
}

/* ===== Image Lightbox ===== */
.lightbox {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.lightbox.active {
    opacity: 1;
    visibility: visible;
}

.lightbox img {
    max-width: 90vw;
    max-height: 90vh;
    object-fit: contain;
    border-radius: 8px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.lightbox-close {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    width: 44px;
    height: 44px;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 50%;
    color: white;
    font-size: 2rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.lightbox-close:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* ===== Contact Form ===== */
.contact-container {
    max-width: 600px;
}

.contact-intro {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 2rem;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 500;
    font-size: 0.9rem;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea {
    padding: 0.875rem 1rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color var(--transition), box-shadow var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0, 119, 181, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-tertiary);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.btn-submit {
    align-self: flex-start;
}

.btn-loading {
    align-items: center;
    gap: 0.5rem;
}

.form-status {
    margin-top: 0.5rem;
}

.empty-state {
    padding: 1.25rem;
    border: 1px dashed var(--border);
    border-radius: 12px;
    color: var(--text-secondary);
    background: var(--bg-secondary);
}

.status-success {
    color: #10b981;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.status-error {
    color: #ef4444;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}