/* ==============================================
   GLOBAL STYLES & RESET
   ============================================== */

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

:root {
    /* Colors - Light mode (default) */
    --color-primary: #000000;
    --color-secondary: #ffffff;
    --color-gray: #666666;
    --color-border: #000000;
    --color-hover-bg: #000000;
    --color-hover-text: #ffffff;
    --color-mobile-overlay: rgba(0, 0, 0, 0.95);
    --color-mobile-text: #ffffff;
    --color-mobile-border: #ffffff;

    /* Typography */
    --font-family: Georgia, Times, serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;

    /* Transitions */
    --transition-speed: 0.3s;

    /* Layout */
    --max-width: 1200px;
    --header-height: 70px;
}

/* Dark mode */
[data-theme="dark"] {
    --color-primary: #ffffff;
    --color-secondary: #000000;
    --color-gray: #999999;
    --color-border: #ffffff;
    --color-hover-bg: #ffffff;
    --color-hover-text: #000000;
    --color-mobile-overlay: rgba(255, 255, 255, 0.95);
    --color-mobile-text: #000000;
    --color-mobile-border: #000000;
}

/* Auto dark mode based on system preference */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --color-primary: #ffffff;
        --color-secondary: #000000;
        --color-gray: #999999;
        --color-border: #ffffff;
        --color-hover-bg: #ffffff;
        --color-hover-text: #000000;
        --color-mobile-overlay: rgba(255, 255, 255, 0.95);
        --color-mobile-text: #000000;
        --color-mobile-border: #000000;
    }
}

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: var(--line-height-base);
    color: var(--color-primary);
    background-color: var(--color-secondary);
    overflow-x: hidden;
    transition: color var(--transition-speed) ease, background-color var(--transition-speed) ease;
}

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ==============================================
   HEADER & NAVIGATION
   ============================================== */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: var(--color-secondary);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: transform var(--transition-speed) ease, background-color var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

.nav {
    height: 100%;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.nav-list {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
}

.nav-link {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    letter-spacing: 0.5px;
    transition: opacity var(--transition-speed) ease, color var(--transition-speed) ease;
    position: relative;
}

.nav-link:hover {
    opacity: 0.6;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--color-primary);
    transition: width var(--transition-speed) ease;
}

.nav-link:hover::after {
    width: 100%;
}


/* Mobile Menu Button */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    top: 50%;
    margin-top: -12px;
}

.menu-text {
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 500;
    letter-spacing: 1px;
    color: var(--color-primary);
    transition: opacity var(--transition-speed) ease, color var(--transition-speed) ease;
}

.mobile-menu-toggle:hover .menu-text {
    opacity: 0.6;
}

.mobile-menu-toggle:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 4px;
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: var(--color-mobile-overlay);
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-speed) ease, visibility var(--transition-speed) ease, background-color var(--transition-speed) ease;
}

.mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

.mobile-menu-content {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
}

.mobile-menu-close {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: none;
    border: 2px solid var(--color-mobile-border);
    color: var(--color-mobile-text);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    font-size: 2rem;
    line-height: 1;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.mobile-menu-close:hover {
    background-color: var(--color-mobile-text);
    color: var(--color-mobile-border);
    transform: rotate(90deg);
}

.mobile-menu-close:focus {
    outline: 2px solid var(--color-mobile-text);
    outline-offset: 4px;
}

.mobile-menu-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
    width: 100%;
}

.mobile-nav-link {
    color: var(--color-mobile-text);
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 400;
    letter-spacing: 1px;
    transition: all var(--transition-speed) ease;
    padding: var(--spacing-sm);
    border-bottom: 2px solid transparent;
}

.mobile-nav-link:hover {
    border-bottom-color: var(--color-mobile-text);
    transform: translateX(5px);
}

.mobile-nav-link:focus {
    outline: 2px solid var(--color-mobile-text);
    outline-offset: 4px;
}

/* ==============================================
   HERO SECTION
   ============================================== */

.hero {
    min-height: calc(100vh - var(--header-height));
    display: flex;
    align-items: center;
    justify-content: center;
    padding: calc(var(--header-height) + var(--spacing-lg)) var(--spacing-md) var(--spacing-lg);
}

.hero.hidden {
    display: none;
}

.profile-image-wrapper {
    display: flex;
    justify-content: center;
    margin-bottom: var(--spacing-lg);
}

.profile-image {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    border: 2px solid var(--color-border);
    overflow: hidden;
    transition: transform var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

.profile-image:hover {
    transform: scale(1.05);
}

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

/* Name with horizontal lines */
.name-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.name {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 300;
    letter-spacing: 2px;
    white-space: nowrap;
}

.name-line {
    flex: 1;
    height: 1px;
    background-color: var(--color-primary);
    border: none;
    max-width: 150px;
}

/* Social Icons */
.social-icons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
}

.social-icon {
    width: 50px;
    height: 50px;
    border: 2px solid var(--color-border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-primary);
    text-decoration: none;
    font-size: 1.25rem;
    transition: all var(--transition-speed) ease;
}

.social-icon:hover {
    background-color: var(--color-hover-bg);
    color: var(--color-hover-text);
    transform: translateY(-3px);
}

/* Hero Bio */
.hero-bio {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.hero-bio-text {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.hero-bio-text:last-child {
    margin-bottom: 0;
}

/* X Logo Styling */
.x-logo {
    font-size: 1.5rem;
    font-weight: bold;
    line-height: 1;
}

.x-logo-contact {
    font-size: 1.25rem;
    font-weight: bold;
    width: 30px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-left: -3px;
}

/* ==============================================
   SECTIONS
   ============================================== */

.section {
    padding: var(--spacing-xl) 0;
    display: none !important;
    min-height: calc(100vh - var(--header-height));
    padding-top: calc(var(--header-height) + var(--spacing-xl));
}

.section.active {
    display: block !important;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 300;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.section-content {
    max-width: 800px;
    margin: 0 auto;
}

.section-divider {
    display: none;
}

/* ==============================================
   BIO SECTION
   ============================================== */

.bio {
    background-color: var(--color-secondary);
}

.bio-text {
    font-size: 1.125rem;
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
    text-align: center;
}

.bio-text:last-child {
    margin-bottom: 0;
}

/* ==============================================
   PUBLIC SPEAKING SECTION
   ============================================== */

.talk-item {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.talk-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.talk-title {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: var(--spacing-xs);
}

.talk-meta {
    font-size: 0.9rem;
    color: var(--color-gray);
    margin-bottom: var(--spacing-sm);
}

.event-link {
    color: var(--color-primary);
    text-decoration: underline;
    transition: opacity var(--transition-speed) ease;
}

.event-link:hover {
    opacity: 0.6;
}

.talk-description {
    line-height: 1.7;
}

.speaking-cta {
    margin-top: var(--spacing-xl);
    padding: var(--spacing-lg);
    border: 2px solid var(--color-border);
    text-align: center;
}

.speaking-cta-title {
    font-size: 1.75rem;
    font-weight: 400;
    margin-bottom: var(--spacing-md);
}

.speaking-cta-text {
    font-size: 1.125rem;
    line-height: 1.7;
    margin-bottom: var(--spacing-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ==============================================
   GITHUB/PROJECTS SECTION
   ============================================== */

.project-item {
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md);
    border: 1px solid var(--color-border);
    transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
}

.project-item:hover {
    transform: translateY(-3px);
    box-shadow: 5px 5px 0 var(--color-primary);
}

.project-item:last-child {
    margin-bottom: 0;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.project-title {
    font-size: 1.4rem;
    font-weight: 500;
}

.project-link {
    color: var(--color-primary);
    font-size: 1.5rem;
    text-decoration: none;
    transition: opacity var(--transition-speed) ease;
}

.project-link:hover {
    opacity: 0.6;
}

.project-description {
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

.project-tags {
    display: flex;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
}

.tag {
    padding: 0.25rem 0.75rem;
    border: 1px solid var(--color-border);
    font-size: 0.85rem;
    letter-spacing: 0.5px;
}

/* ==============================================
   YOUTUBE SECTION
   ============================================== */

.section-intro {
    text-align: center;
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.video-item {
    border: 1px solid var(--color-border);
    transition: transform var(--transition-speed) ease;
}

.video-item:hover {
    transform: translateY(-3px);
}

.video-thumbnail {
    width: 100%;
    aspect-ratio: 16 / 9;
    background-color: var(--color-secondary);
    border-bottom: 1px solid var(--color-border);
}

.video-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    font-size: 3rem;
    color: var(--color-primary);
    opacity: 0.3;
}

.video-placeholder span {
    font-size: 0.9rem;
}

.video-title {
    font-size: 1.125rem;
    font-weight: 500;
    padding: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
}

.video-description {
    padding: 0 var(--spacing-sm) var(--spacing-sm);
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--color-gray);
}

.cta-button {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--color-border);
    background-color: var(--color-secondary);
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
    letter-spacing: 1px;
    transition: all var(--transition-speed) ease;
    margin: 0 auto;
    display: block;
    text-align: center;
    max-width: 200px;
}

.cta-button:hover {
    background-color: var(--color-black);
    color: var(--color-white);
}

/* ==============================================
   CONTACT SECTION
   ============================================== */

.contact-intro {
    text-align: center;
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    max-width: 500px;
    margin: 0 auto;
}

.contact-method {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    border: 1px solid var(--color-border);
    color: var(--color-primary);
    text-decoration: none;
    transition: all var(--transition-speed) ease;
}

.contact-method:hover {
    background-color: var(--color-black);
    color: var(--color-white);
    transform: translateX(5px);
}

.contact-method i {
    font-size: 1.25rem;
    width: 30px;
}

/* ==============================================
   FOOTER
   ============================================== */

.footer {
    padding: var(--spacing-lg) 0;
    border-top: 1px solid var(--color-border);
    text-align: center;
}

.footer p {
    font-size: 0.9rem;
    color: var(--color-gray);
}

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

/* Tablet */
@media (max-width: 768px) {
    :root {
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
    }

    /* Show mobile menu button, hide desktop nav */
    .mobile-menu-toggle {
        display: block;
    }

    .nav {
        justify-content: center;
        position: relative;
    }

    .nav-list {
        display: none;
    }

    .profile-image {
        width: 160px;
        height: 160px;
    }

    .name {
        font-size: 2rem;
    }

    .social-icon {
        width: 45px;
        height: 45px;
        font-size: 1.125rem;
    }

    .bio-text {
        font-size: 1rem;
    }

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

/* Mobile */
@media (max-width: 480px) {
    :root {
        --spacing-sm: 0.75rem;
        --spacing-md: 1.5rem;
        --spacing-lg: 2.5rem;
        --spacing-xl: 3rem;
    }

    .container {
        padding: 0 var(--spacing-sm);
    }

    .nav {
        padding: 0 var(--spacing-sm);
    }

    /* Show mobile menu button, hide desktop nav */
    .mobile-menu-toggle {
        display: block;
    }

    .nav-list {
        display: none;
    }

    .mobile-nav-link {
        font-size: 1.25rem;
    }

    .hero {
        padding: calc(var(--header-height) + var(--spacing-md)) var(--spacing-sm) var(--spacing-md);
    }

    .profile-image {
        width: 140px;
        height: 140px;
    }

    .name-wrapper {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .name-line {
        width: 100px;
        max-width: none;
    }

    .social-icons {
        gap: var(--spacing-sm);
        margin-bottom: var(--spacing-md);
    }

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

    .section-title {
        font-size: 1.75rem;
    }

    .project-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-xs);
    }
}

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

/* Fade in animation for sections */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ==============================================
   ACCESSIBILITY
   ============================================== */

/* Focus styles */
a:focus,
button:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Screen reader only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}