/* =============================================
   Portfolio — Calm, Confident, Professional
   Design Philosophy: Less is more. Let work speak.
   Optimized for clarity, affordance, and comfort.
   ============================================= */

:root {
    /* Refined neutral palette - warm undertones */
    --bg-primary: #0f0f10;
    --bg-secondary: #161618;
    --bg-elevated: #1c1c1f;
    
    --text-primary: #fafafa;
    --text-secondary: #a1a1a6;
    --text-muted: #6b6b70;
    
    --border: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(255, 255, 255, 0.15);
    
    /* Single accent - subtle blue-violet, not aggressive */
    --accent: #6366f1;
    --accent-muted: rgba(99, 102, 241, 0.15);
    --accent-focus: rgba(99, 102, 241, 0.4);
    
    /* Typography */
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Spacing - slightly reduced for better rhythm */
    --container: 1100px;
    --text-max-width: 65ch;
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 40px;
    --space-2xl: 64px;
    --space-3xl: 100px;
    
    /* Motion - faster, more responsive */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
    --duration: 0.15s;
    --duration-medium: 0.25s;
    
    /* Border radius - subtle curves */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
}

/* Light theme */
[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f8f8;
    --bg-elevated: #ffffff;
    
    --text-primary: #0f0f10;
    --text-secondary: #52525b;
    --text-muted: #71717a;
    
    --border: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(0, 0, 0, 0.15);
    
    --accent-muted: rgba(99, 102, 241, 0.1);
    --accent-focus: rgba(99, 102, 241, 0.3);
}

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

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

body {
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

::selection {
    background: var(--accent);
    color: white;
}

/* =============================================
   Focus States - Accessibility
   ============================================= */
:focus {
    outline: none;
}

:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Container */
.container {
    width: 100%;
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* =============================================
   Typography - Improved hierarchy
   ============================================= */
h1, h2, h3, h4 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

h1 { font-size: clamp(2.25rem, 5vw, 3.5rem); font-weight: 700; }
h2 { font-size: clamp(1.75rem, 3vw, 2.25rem); font-weight: 700; }
h3 { font-size: 1.25rem; font-weight: 600; }
h4 { font-size: 0.875rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-muted); }

p {
    color: var(--text-secondary);
    max-width: var(--text-max-width);
}

/* =============================================
   Header
   ============================================= */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-md) 0;
    transition: background var(--duration) var(--ease),
                border-color var(--duration) var(--ease);
}

.header.scrolled {
    background: rgba(15, 15, 16, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

[data-theme="light"] .header.scrolled {
    background: rgba(255, 255, 255, 0.85);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-lg);
}

.logo {
    font-size: 1.125rem;
    font-weight: 700;
    text-decoration: none;
    padding: var(--space-sm) var(--space-md);
    background: var(--accent);
    color: white;
    border-radius: var(--radius-sm);
    transition: opacity var(--duration) var(--ease);
}

.logo:hover {
    opacity: 0.9;
}

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

.nav-links a {
    position: relative;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    padding: var(--space-xs) 0;
    transition: color var(--duration) var(--ease);
}

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

/* Active nav indicator */
.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--accent);
    border-radius: 1px;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

/* Theme Toggle */
.theme-toggle {
    position: relative;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--duration) var(--ease);
}

.theme-toggle:hover {
    color: var(--text-primary);
    border-color: var(--border-hover);
    background: var(--bg-elevated);
}

.theme-toggle:active {
    transform: scale(0.95);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
    position: absolute;
    transition: all var(--duration-medium) var(--ease);
}

.icon-sun {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
}

.icon-moon {
    opacity: 1;
    transform: rotate(0) scale(1);
}

[data-theme="light"] .icon-sun {
    opacity: 1;
    transform: rotate(0) scale(1);
}

[data-theme="light"] .icon-moon {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
}

.nav-cta {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    text-decoration: none;
    padding: var(--space-sm) var(--space-md);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    transition: all var(--duration) var(--ease);
}

.nav-cta:hover {
    border-color: var(--border-hover);
    background: var(--bg-elevated);
}

.nav-cta:active {
    transform: scale(0.98);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 12px;
    background: none;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    height: 2px;
    width: 100%;
    background: var(--text-primary);
    transition: all var(--duration-medium) var(--ease);
}

.menu-toggle.active span:first-child {
    transform: rotate(45deg) translate(4px, 4px);
}

.menu-toggle.active span:last-child {
    transform: rotate(-45deg) translate(4px, -4px);
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    inset: 0;
    z-index: 99;
    background: var(--bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--duration-medium) var(--ease);
}

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

.mobile-nav {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-xl);
}

.mobile-nav a {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
    padding: var(--space-sm) var(--space-lg);
}

.mobile-nav a:active {
    opacity: 0.7;
}

/* =============================================
   Buttons - With active feedback
   ============================================= */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-md) var(--space-lg);
    font-family: inherit;
    font-size: 0.9375rem;
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--duration) var(--ease);
    border: none;
}

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

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
    opacity: 0.85;
}

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

.btn-secondary:hover {
    border-color: var(--border-hover);
    background: var(--bg-elevated);
}

.btn-secondary:active {
    transform: scale(0.98);
}

/* =============================================
   Hero
   ============================================= */
.hero {
    padding: var(--space-3xl) 0 var(--space-2xl);
    min-height: 65vh;
    display: flex;
    align-items: center;
}

.hero-label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--accent);
    margin-bottom: var(--space-md);
}

.hero-title {
    margin-bottom: var(--space-lg);
    max-width: 700px;
}

.hero-desc {
    font-size: 1.125rem;
    max-width: 560px;
    margin-bottom: var(--space-xl);
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: var(--space-md);
}

/* =============================================
   Trust Bar
   ============================================= */
.trust-bar {
    padding: var(--space-lg) 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.trust-bar .container {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.trust-label {
    font-size: 0.8125rem;
    color: var(--text-muted);
    white-space: nowrap;
}

.trust-logos {
    display: flex;
    gap: var(--space-xl);
    flex-wrap: wrap;
}

.trust-logos span {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--text-muted);
    opacity: 0.7;
}

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

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

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

.section-header h2 {
    margin-bottom: var(--space-sm);
}

.section-header p {
    font-size: 1.0625rem;
}

/* =============================================
   Projects - With card affordances
   ============================================= */
.projects {
    display: flex;
    flex-direction: column;
    gap: var(--space-2xl);
}

.project {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    align-items: center;
    cursor: default;
}

.project:nth-child(even) {
    direction: rtl;
}

.project:nth-child(even) > * {
    direction: ltr;
}

.project-tag {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--accent);
    background: var(--accent-muted);
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
    margin-bottom: var(--space-md);
}

.project-info h3 {
    margin-bottom: var(--space-md);
}

.project-info p {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: var(--space-lg);
}

.project-meta {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

.project-meta span {
    font-size: 0.8125rem;
    color: var(--text-muted);
    padding: var(--space-xs) var(--space-sm);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
}

.project-visual {
    aspect-ratio: 4/3;
}

.project-preview {
    width: 100%;
    height: 100%;
    background: linear-gradient(
        135deg,
        hsl(var(--accent, 240) 70% 60% / 0.1) 0%,
        hsl(calc(var(--accent, 240) + 30) 70% 70% / 0.05) 100%
    );
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: all var(--duration-medium) var(--ease);
}

.project:hover .project-preview {
    border-color: var(--border-hover);
    background: linear-gradient(
        135deg,
        hsl(var(--accent, 240) 70% 60% / 0.15) 0%,
        hsl(calc(var(--accent, 240) + 30) 70% 70% / 0.08) 100%
    );
    transform: scale(1.01);
}

/* =============================================
   About
   ============================================= */
.about-layout {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: var(--space-3xl);
}

.about-content h2 {
    margin-bottom: var(--space-lg);
}

.about-text {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.about-text p {
    font-size: 1.0625rem;
    line-height: 1.8;
}

.about-skills {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
}

.skill-group h4 {
    margin-bottom: var(--space-md);
}

.skill-group ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.skill-group li {
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

/* =============================================
   Experience
   ============================================= */
.experience-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.experience-item {
    padding: var(--space-lg);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    transition: all var(--duration) var(--ease);
}

.experience-item:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
}

.exp-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--space-md);
    margin-bottom: var(--space-sm);
}

.exp-header h3 {
    font-size: 1.125rem;
    margin-bottom: var(--space-xs);
}

.exp-company {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.exp-date {
    font-size: 0.8125rem;
    color: var(--text-muted);
    white-space: nowrap;
}

.exp-desc {
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* Current role highlight */
.experience-item.current {
    border-color: var(--accent);
    background: var(--accent-muted);
}

.experience-item.current .exp-company::after {
    content: 'Current';
    display: inline-block;
    margin-left: var(--space-sm);
    font-size: 0.625rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--accent);
    background: var(--bg-primary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    vertical-align: middle;
}

/* =============================================
   Contact
   ============================================= */
.contact-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
}

.contact-info h2 {
    margin-bottom: var(--space-md);
}

.contact-info > p {
    font-size: 1.0625rem;
    line-height: 1.7;
    margin-bottom: var(--space-xl);
}

.contact-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.contact-link {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
    padding: var(--space-md);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    text-decoration: none;
    cursor: pointer;
    transition: all var(--duration) var(--ease);
}

.contact-link:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
    transform: translateX(4px);
}

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

.link-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.link-value {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-primary);
}

/* Contact Form */
.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.form-group label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: var(--space-md);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    transition: all var(--duration) var(--ease);
}

.form-group input:hover,
.form-group textarea:hover {
    border-color: var(--border-hover);
}

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

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

/* Form feedback placeholder space */
.form-feedback {
    min-height: 20px;
    font-size: 0.875rem;
}

.form-feedback.error {
    color: #ef4444;
}

.form-feedback.success {
    color: #10b981;
}

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

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

.footer-content p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

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

.footer-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    color: var(--text-muted);
    border-radius: var(--radius-sm);
    transition: all var(--duration) var(--ease);
}

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

.footer-links a:active {
    transform: scale(0.95);
}

/* =============================================
   Animations - Faster, purposeful
   ============================================= */
.fade-in {
    opacity: 0;
    transform: translateY(16px);
    transition: all 0.45s var(--ease);
}

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

/* =============================================
   Responsive
   ============================================= */
@media (max-width: 1024px) {
    .project {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
    
    .project:nth-child(even) {
        direction: ltr;
    }
    
    .project-visual {
        order: -1;
    }
    
    .about-layout {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
    
    .about-skills {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .contact-layout {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
}

@media (max-width: 768px) {
    :root {
        --space-3xl: 64px;
        --space-2xl: 48px;
    }
    
    .nav-links,
    .nav-cta {
        display: none;
    }
    
    .menu-toggle {
        display: flex;
    }
    
    .hero {
        min-height: auto;
        padding: var(--space-2xl) 0;
    }
    
    .hero-actions {
        flex-direction: column;
        gap: var(--space-sm);
    }
    
    .hero-actions .btn {
        width: 100%;
        justify-content: center;
    }
    
    .trust-bar .container {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-sm);
    }
    
    .about-skills {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        gap: var(--space-lg);
        text-align: center;
    }
    
    .exp-header {
        flex-direction: column;
        gap: var(--space-xs);
    }
    
    .exp-date {
        order: -1;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-md);
    }
    
    .about-skills {
        grid-template-columns: 1fr 1fr;
    }
}

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