/* ========================================
   ANKIT GUPTA - SWISS PRECISION MINIMAL
   Professional Portfolio
   ======================================== */

/* CSS Variables */
:root {
    /* Colors - Monochrome + Ocean Blue Accent */
    --color-white: #FFFFFF;
    --color-surface: #F8F9FA;
    --color-text-primary: #1A1A1A;
    --color-text-secondary: #6B7280;
    --color-text-tertiary: #9CA3AF;
    --color-accent: #0F4C81;
    --color-accent-light: #1E6BA8;
    --color-border: #E5E7EB;
    --color-shadow: rgba(0, 0, 0, 0.08);

    /* Typography */
    --font-display: 'Outfit', sans-serif;
    --font-body: 'Manrope', sans-serif;

    /* Spacing - 8px system */
    --space-xs: 0.5rem;     /* 8px */
    --space-sm: 1rem;       /* 16px */
    --space-md: 1.5rem;     /* 24px */
    --space-lg: 2rem;       /* 32px */
    --space-xl: 3rem;       /* 48px */
    --space-2xl: 4rem;      /* 64px */
    --space-3xl: 6rem;      /* 96px */

    /* Layout */
    --container-max: 1200px;
    --content-max: 720px;

    /* Transitions */
    --ease: cubic-bezier(0.4, 0.0, 0.2, 1);
    --duration: 0.3s;
}

/* ========================================
   RESET & BASE
   ======================================== */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-weight: 400;
    line-height: 1.6;
    color: var(--color-text-primary);
    background: var(--color-white);
    overflow-x: hidden;
}

/* ========================================
   TYPOGRAPHY
   ======================================== */

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 600;
    line-height: 1.2;
    color: var(--color-text-primary);
}

h1 { font-size: clamp(2.5rem, 6vw, 4rem); }
h2 { font-size: clamp(2rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: var(--space-md);
    color: var(--color-text-secondary);
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--duration) var(--ease);
}

a:hover {
    color: var(--color-accent-light);
}

ul, ol {
    margin: 0;
    padding: 0;
    list-style: none;
}

/* ========================================
   DIAGONAL ACCENT LINE
   ======================================== */

.diagonal-accent {
    position: fixed;
    top: 0;
    right: 20%;
    width: 2px;
    height: 100vh;
    background: linear-gradient(
        to bottom,
        transparent 0%,
        var(--color-accent) 10%,
        var(--color-accent) 90%,
        transparent 100%
    );
    transform: rotate(2deg);
    transform-origin: top;
    z-index: 1;
    opacity: 0.15;
    pointer-events: none;
}

/* ========================================
   NAVIGATION
   ======================================== */

.nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: var(--space-md) 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    transition: all var(--duration) var(--ease);
}

.nav.scrolled {
    padding: var(--space-sm) 0;
    box-shadow: 0 4px 12px var(--color-shadow);
}

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

.nav-logo {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: -0.02em;
}

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

.nav-link {
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    position: relative;
    transition: color var(--duration) var(--ease);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-accent);
    transition: width var(--duration) var(--ease);
}

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-xs);
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    transition: all var(--duration) var(--ease);
}

.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(7px, -7px);
}

/* Mobile Menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: 73px;
    left: 0;
    width: 100%;
    background: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-lg);
    flex-direction: column;
    gap: var(--space-md);
    z-index: 999;
    transform: translateY(-100%);
    opacity: 0;
    transition: all var(--duration) var(--ease);
}

.mobile-menu.active {
    transform: translateY(0);
    opacity: 1;
}

.mobile-link {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--color-text-primary);
    padding: var(--space-sm) 0;
}

/* ========================================
   CONTAINER & LAYOUT
   ======================================== */

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

section {
    padding: var(--space-3xl) 0;
    position: relative;
}

/* Section Numbers */
.section-number {
    font-family: var(--font-display);
    font-size: 5rem;
    font-weight: 700;
    color: var(--color-accent);
    opacity: 0.08;
    position: absolute;
    top: var(--space-2xl);
    left: var(--space-lg);
    line-height: 1;
    pointer-events: none;
}

.section-header {
    margin-bottom: var(--space-3xl);
    position: relative;
}

.section-title {
    margin-bottom: var(--space-sm);
    color: var(--color-text-primary);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    max-width: 600px;
}

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

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: calc(73px + var(--space-2xl));
    background: linear-gradient(135deg, var(--color-white) 0%, var(--color-surface) 100%);
}

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

.hero-text {
    max-width: var(--content-max);
}

.hero-title {
    margin-bottom: var(--space-md);
    background: linear-gradient(135deg, var(--color-text-primary) 0%, var(--color-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--color-text-primary);
    margin-bottom: var(--space-lg);
    line-height: 1.4;
}

.hero-subtitle .highlight {
    color: var(--color-accent);
    font-weight: 600;
}

.hero-description {
    font-size: 1.125rem;
    line-height: 1.8;
    margin-bottom: var(--space-xl);
}

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

.hero-image {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-img {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 20px 60px var(--color-shadow);
    position: relative;
    z-index: 2;
}

.image-accent {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 100%;
    max-width: 400px;
    height: calc(100% - 40px);
    border: 2px solid var(--color-accent);
    border-radius: 8px;
    z-index: 1;
}

/* ========================================
   BUTTONS
   ======================================== */

.btn {
    display: inline-block;
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 500;
    padding: var(--space-sm) var(--space-lg);
    border-radius: 4px;
    transition: all var(--duration) var(--ease);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn-primary {
    background: var(--color-accent);
    color: var(--color-white);
    border-color: var(--color-accent);
}

.btn-primary:hover {
    background: var(--color-accent-light);
    border-color: var(--color-accent-light);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(15, 76, 129, 0.2);
}

.btn-secondary {
    background: transparent;
    color: var(--color-accent);
    border-color: var(--color-accent);
}

.btn-secondary:hover {
    background: var(--color-accent);
    color: var(--color-white);
    transform: translateY(-2px);
}

/* ========================================
   EXPERIENCE SECTION
   ======================================== */

.experience {
    background: var(--color-white);
}

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

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 2px;
    height: 100%;
    background: linear-gradient(
        to bottom,
        var(--color-accent) 0%,
        var(--color-border) 50%,
        transparent 100%
    );
}

.timeline-item {
    position: relative;
    margin-bottom: var(--space-3xl);
    padding-bottom: var(--space-xl);
}

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

.timeline-marker {
    position: absolute;
    left: calc(-1 * var(--space-2xl) - 6px);
    top: 0;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--color-white);
    border: 3px solid var(--color-accent);
    box-shadow: 0 0 0 4px var(--color-white);
}

.timeline-content {
    background: var(--color-surface);
    padding: var(--space-lg);
    border-radius: 8px;
    border: 1px solid var(--color-border);
    transition: all var(--duration) var(--ease);
}

.timeline-content:hover {
    transform: translateX(4px);
    box-shadow: 0 8px 24px var(--color-shadow);
}

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

.job-title {
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-xs);
}

.job-company {
    font-size: 1rem;
    color: var(--color-text-secondary);
}

.job-company a {
    color: var(--color-accent);
    font-weight: 500;
}

.job-period {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-tertiary);
    white-space: nowrap;
    background: var(--color-white);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
    border: 1px solid var(--color-border);
}

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

.job-highlights {
    list-style: none;
    margin-bottom: var(--space-md);
}

.job-highlights li {
    position: relative;
    padding-left: var(--space-md);
    margin-bottom: var(--space-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

.job-highlights li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: 600;
}

.job-logo {
    margin-top: var(--space-md);
}

.job-logo img {
    max-width: 200px;
    height: auto;
    opacity: 0.7;
    transition: opacity var(--duration) var(--ease);
}

.job-logo img:hover {
    opacity: 1;
}

/* ========================================
   SKILLS SECTION
   ======================================== */

.skills {
    background: var(--color-surface);
}

.skills-grid {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    max-width: 900px;
}

.skill-tag {
    display: inline-block;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text-primary);
    background: var(--color-white);
    padding: var(--space-sm) var(--space-md);
    border-radius: 6px;
    border: 1px solid var(--color-border);
    transition: all var(--duration) var(--ease);
}

.skill-tag:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--color-shadow);
    border-color: var(--color-accent);
    color: var(--color-accent);
}

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

.projects {
    background: var(--color-white);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--space-lg);
}

.project-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--space-lg);
    transition: all var(--duration) var(--ease);
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px var(--color-shadow);
    border-color: var(--color-accent);
}

.project-content {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.project-title {
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-sm);
}

.project-description {
    flex: 1;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: var(--space-md);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
    margin-bottom: var(--space-md);
}

.tag {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-accent);
    background: rgba(15, 76, 129, 0.1);
    padding: 4px 12px;
    border-radius: 4px;
}

.project-link {
    font-weight: 500;
    color: var(--color-accent);
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    transition: all var(--duration) var(--ease);
}

.project-link:hover {
    gap: var(--space-sm);
}

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

.footer {
    background: var(--color-text-primary);
    color: var(--color-white);
    padding: var(--space-3xl) 0 var(--space-lg);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--space-3xl);
    margin-bottom: var(--space-2xl);
}

.footer-title {
    color: var(--color-white);
    margin-bottom: var(--space-md);
}

.footer-text {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: var(--space-md);
}

.footer-email {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--color-accent-light);
}

.footer-email:hover {
    color: var(--color-white);
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    align-items: flex-start;
}

.footer-link {
    font-size: 1rem;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.7);
    transition: all var(--duration) var(--ease);
}

.footer-link:hover {
    color: var(--color-white);
    transform: translateX(4px);
}

.footer-bottom {
    padding-top: var(--space-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.875rem;
}

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

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s var(--ease);
}

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

/* Stagger delays for timeline items */
.timeline-item:nth-child(1) { transition-delay: 0.1s; }
.timeline-item:nth-child(2) { transition-delay: 0.2s; }
.timeline-item:nth-child(3) { transition-delay: 0.3s; }
.timeline-item:nth-child(4) { transition-delay: 0.4s; }
.timeline-item:nth-child(5) { transition-delay: 0.5s; }
.timeline-item:nth-child(6) { transition-delay: 0.6s; }
.timeline-item:nth-child(7) { transition-delay: 0.7s; }

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

@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        gap: var(--space-2xl);
    }

    .hero-image {
        order: -1;
    }

    .section-number {
        font-size: 4rem;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
    }
}

@media (max-width: 768px) {
    :root {
        --space-3xl: 4rem;
    }

    .nav-links {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .mobile-menu {
        display: flex;
    }

    .diagonal-accent {
        right: 10%;
    }

    .section-number {
        font-size: 3rem;
        top: var(--space-lg);
    }

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

    .timeline-marker {
        left: calc(-1 * var(--space-lg) - 6px);
    }

    .job-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .job-period {
        white-space: normal;
    }

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

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

    .btn {
        width: 100%;
        text-align: center;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 0 var(--space-md);
    }

    section {
        padding: var(--space-2xl) 0;
    }

    .profile-img {
        max-width: 300px;
    }

    .image-accent {
        max-width: 300px;
    }
}

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

@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;
    }
}

/* Focus styles */
*:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

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

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