/* ============================================
   DESIGN SYSTEM — Mehdi Ali Personal Website
   Inspired by chester.how
   ============================================ */

/* --- Custom Properties --- */
:root {
    /* Color Palette — Warm cream background with bronze accents */
    --bg-primary: #faf6f0;
    --bg-secondary: #f3ece2;
    --bg-card: rgba(139, 90, 43, 0.04);
    --bg-card-hover: rgba(139, 90, 43, 0.08);
    --bg-alt: #f5efe6;

    --text-primary: #3d2b1f;
    --text-secondary: #6b5744;
    --text-muted: #9a8873;

    --accent: #8b5a2b;
    --accent-soft: rgba(139, 90, 43, 0.12);
    --accent-glow: rgba(139, 90, 43, 0.2);

    --border: rgba(139, 90, 43, 0.12);
    --border-hover: rgba(139, 90, 43, 0.22);

    /* Typography */
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2.5rem;
    --space-2xl: 4rem;
    --space-3xl: 6rem;
    --space-4xl: 8rem;

    /* Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 50%;

    /* Transitions */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
    --transition-fast: 0.2s var(--ease-out);
    --transition-med: 0.4s var(--ease-out);
    --transition-slow: 0.6s var(--ease-out);
}

/* --- Reset & Base --- */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-primary);
    background: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-fast);
}

h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    line-height: 1.2;
    font-weight: 600;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* --- Reveal Animation --- */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s var(--ease-out), transform 0.8s var(--ease-out);
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- Navigation --- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-md) 0;
    transition: background var(--transition-med), box-shadow var(--transition-med), padding var(--transition-med);
}

.nav.scrolled {
    background: rgba(250, 246, 240, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 0 var(--border);
    padding: var(--space-sm) 0;
}

.nav-inner {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.nav-logo:hover {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: var(--space-lg);
}

.nav-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
    padding: var(--space-xs) 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    border-radius: 1px;
    transition: width var(--transition-fast);
}

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

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

/* Mobile toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    width: 22px;
    height: 2px;
    background: var(--text-secondary);
    border-radius: 1px;
    transition: transform var(--transition-fast), opacity var(--transition-fast);
}

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

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

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

.mobile-menu {
    display: none;
    flex-direction: column;
    padding: var(--space-md) var(--space-lg) var(--space-lg);
    gap: var(--space-sm);
}

.mobile-menu.open {
    display: flex;
}

.mobile-link {
    font-size: 1rem;
    color: var(--text-secondary);
    padding: var(--space-sm) 0;
    border-bottom: 1px solid var(--border);
}

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

/* --- Hero --- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    padding: var(--space-4xl) 0 var(--space-3xl);
}

.hero-bg-glow {
    position: absolute;
    top: 15%;
    left: 50%;
    transform: translateX(-50%);
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
    opacity: 0.15;
    filter: blur(80px);
    pointer-events: none;
    z-index: 0;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 650px;
    margin: 0 auto;
}

.hero-avatar {
    display: inline-block;
    position: relative;
    margin-bottom: var(--space-xl);
}

.avatar-ring {
    width: 100px;
    height: 100px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--accent), #6d4520);
    padding: 3px;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: pulse-ring 3s ease-in-out infinite;
}

.avatar-placeholder {
    width: 100%;
    height: 100%;
    border-radius: var(--radius-full);
    background: var(--bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-heading);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 0.05em;
}

@keyframes pulse-ring {

    0%,
    100% {
        box-shadow: 0 0 0 0 var(--accent-glow);
    }

    50% {
        box-shadow: 0 0 0 12px transparent;
    }
}

.status-dot {
    position: absolute;
    bottom: 4px;
    right: 4px;
    width: 16px;
    height: 16px;
    background: #22c55e;
    border: 3px solid var(--bg-primary);
    border-radius: var(--radius-full);
    animation: blink 3s ease-in-out infinite;
}

@keyframes blink {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.4;
    }
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: var(--space-md);
}

.highlight {
    color: var(--accent);
    position: relative;
}

.hero-tagline {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.hero-description {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-xl);
}

.text-link {
    color: var(--accent);
    font-weight: 500;
    position: relative;
    transition: color var(--transition-fast);
}

.text-link::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 1px;
    background: var(--accent);
    opacity: 0.3;
    transition: opacity var(--transition-fast);
}

.text-link:hover::after {
    opacity: 1;
}

.highlight-subtle {
    color: var(--text-primary);
    font-weight: 500;
}

.hero-cta {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-lg);
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
}

.btn-primary {
    background: var(--accent);
    color: #faf6f0;
}

.btn-primary:hover {
    background: #6d4520;
    transform: translateY(-2px);
    box-shadow: 0 8px 24px var(--accent-glow);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-ghost:hover {
    border-color: var(--border-hover);
    color: var(--text-primary);
    transform: translateY(-2px);
}

/* Scroll indicator */
.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, var(--accent), transparent);
    animation: scroll-anim 2s ease-in-out infinite;
}

@keyframes scroll-anim {
    0% {
        opacity: 0;
        transform: scaleY(0);
        transform-origin: top;
    }

    50% {
        opacity: 1;
        transform: scaleY(1);
        transform-origin: top;
    }

    100% {
        opacity: 0;
        transform: scaleY(1);
        transform-origin: bottom;
    }
}

/* --- Sections --- */
.section {
    padding: var(--space-3xl) 0;
}

.section-alt {
    background: var(--bg-alt);
}

.section-header {
    margin-bottom: var(--space-2xl);
}

.section-label {
    display: block;
    font-family: var(--font-heading);
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: var(--space-sm);
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    letter-spacing: -0.03em;
}

/* --- Glass Card --- */
.glass-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: background var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.glass-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(139, 90, 43, 0.08);
}

/* --- About Section --- */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
}

.about-card .card-icon {
    font-size: 2rem;
    margin-bottom: var(--space-md);
}

.about-card h3 {
    font-size: 1.1rem;
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.about-degree {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.about-minor {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--space-xs);
}

.about-school {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--space-md);
}

.about-badge {
    display: inline-block;
    background: var(--accent-soft);
    color: var(--accent);
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-weight: 500;
}

.location-tags {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-md);
    flex-wrap: wrap;
}

.location-tag {
    background: var(--bg-card-hover);
    border: 1px solid var(--border);
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
}

/* --- Research Section --- */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: var(--space-lg);
}

.research-card .research-icon {
    font-size: 1.75rem;
    margin-bottom: var(--space-md);
}

.research-card h3 {
    font-size: 1rem;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.research-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
}

.research-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

.tag {
    background: var(--accent-soft);
    color: var(--accent);
    padding: 2px 10px;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 500;
}

/* --- Skills Section --- */
.skills-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
}

.skill-group {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    transition: border-color var(--transition-fast);
}

.skill-group:hover {
    border-color: var(--border-hover);
}

.skill-group-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: var(--space-md);
}

.skill-pills {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
}

.skill-pill {
    background: var(--bg-card-hover);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 6px 14px;
    border-radius: var(--radius-xl);
    font-size: 0.85rem;
    font-weight: 400;
    transition: all var(--transition-fast);
}

.skill-pill:hover {
    background: var(--accent-soft);
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-2px);
}

/* --- Languages Section --- */
.languages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: var(--space-lg);
}

.lang-card {
    text-align: center;
    padding: var(--space-xl) var(--space-lg);
}

.lang-flag {
    font-size: 2rem;
    margin-bottom: var(--space-sm);
}

.lang-card h3 {
    font-size: 1rem;
    margin-bottom: var(--space-md);
    color: var(--text-primary);
}

.lang-bar-container {
    width: 100%;
    height: 4px;
    background: var(--bg-card-hover);
    border-radius: 2px;
    overflow: hidden;
    margin-bottom: var(--space-sm);
}

.lang-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), #b8783d);
    border-radius: 2px;
    width: 0;
    transition: width 1.2s var(--ease-out);
}


.lang-level {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* --- Interests Section --- */
.interests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--space-lg);
}

.interest-card {
    text-align: center;
    padding: var(--space-xl);
}

.interest-icon {
    font-size: 2rem;
    margin-bottom: var(--space-md);
}

.interest-card h3 {
    font-size: 1rem;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.interest-card p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

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

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-xl);
}

.footer-logo {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.footer-brand p {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: var(--space-xs);
}

.footer-links {
    display: flex;
    gap: var(--space-lg);
}

.footer-link {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--space-xl);
    border-top: 1px solid var(--border);
}

.footer-bottom p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

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

    .nav-toggle {
        display: flex;
    }

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

    .skills-container {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        gap: var(--space-lg);
        text-align: center;
    }

    .hero-title {
        font-size: clamp(1.75rem, 6vw, 2.25rem);
    }

    .hero-description {
        font-size: 0.95rem;
    }
}

@media (max-width: 480px) {
    .languages-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }
}