:root {
    --board: #0b0d10;
    --board-2: #12151c;
    --chalk: #f4f7fb;
    --chalk-muted: #b9c2cf;
    --accent: #5ef0ff;
    --accent-2: #ffd166;
    --line: rgba(244, 247, 251, 0.22);
    --card: rgba(18, 22, 30, 0.85);
    --shadow: 0 18px 40px rgba(0, 0, 0, 0.4);
    --radius: 24px;
    --nav-height: 76px;
    --max-width: 1120px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Sora', sans-serif;
    background-color: var(--board);
    color: var(--chalk);
    line-height: 1.6;
    font-size: 1rem;
    min-height: 100vh;
    overflow-x: hidden;
    position: relative;
    background-image:
        radial-gradient(circle at 20% 20%, rgba(94, 240, 255, 0.08), transparent 40%),
        radial-gradient(circle at 80% 10%, rgba(255, 209, 102, 0.08), transparent 45%),
        linear-gradient(135deg, #0b0d10 0%, #0f141b 55%, #0b0d10 100%);
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: radial-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px);
    background-size: 6px 6px;
    opacity: 0.35;
    pointer-events: none;
    z-index: 0;
}

body::after {
    content: '';
    position: fixed;
    inset: 0;
    background-image: repeating-linear-gradient(
        120deg,
        rgba(255, 255, 255, 0.03),
        rgba(255, 255, 255, 0.03) 2px,
        transparent 2px,
        transparent 8px
    );
    opacity: 0.2;
    pointer-events: none;
    z-index: 0;
}

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

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

main {
    padding-top: var(--nav-height);
    position: relative;
    z-index: 1;
}

section {
    padding: 5.5rem 1.5rem;
    scroll-margin-top: calc(var(--nav-height) + 24px);
}

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
}

h1,
h2,
h3,
.brand-name {
    font-family: 'Kalam', cursive;
}

h1 {
    font-size: clamp(2.6rem, 4vw, 4.2rem);
    line-height: 1.1;
}

h2 {
    font-size: clamp(2rem, 3vw, 3.2rem);
}

h3 {
    font-size: 1.6rem;
}

p {
    color: var(--chalk-muted);
}

body[data-active-track="ai"] [data-track="sde"]:not(.track-btn) {
    display: none !important;
}

body[data-active-track="sde"] [data-track="ai"]:not(.track-btn) {
    display: none !important;
}

.section-header {
    display: flex;
    flex-direction: column;
    gap: 0.9rem;
    margin-bottom: 2.4rem;
}

.section-header p {
    max-width: 720px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* Navigation */
.site-nav {
    position: fixed;
    top: 0;
    width: 100%;
    height: var(--nav-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2.5rem;
    background: rgba(11, 13, 16, 0.88);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--line);
    z-index: 10;
}

.brand {
    display: flex;
    align-items: center;
    gap: 1.2rem;
}

.brand-name {
    font-size: 1.6rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.track-toggle {
    position: relative;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: center;
    gap: 0.2rem;
    padding: 0.25rem;
    border-radius: 999px;
    border: 1px solid var(--line);
    background: rgba(9, 12, 16, 0.7);
    min-width: 160px;
}

.track-toggle::before {
    content: '';
    position: absolute;
    top: 4px;
    bottom: 4px;
    left: 4px;
    width: calc(50% - 4px);
    border-radius: 999px;
    background: var(--accent);
    transition: transform 0.3s ease, background 0.3s ease;
    z-index: 0;
}

body[data-active-track="sde"] .track-toggle::before {
    transform: translateX(100%);
    background: var(--accent-2);
}

.track-btn {
    position: relative;
    z-index: 1;
    border: none;
    background: transparent;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--chalk-muted);
    padding: 0.35rem 0.6rem;
    cursor: pointer;
}

.track-btn.active {
    color: #071017;
    font-weight: 700;
}

.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    font-weight: 600;
    font-size: 0.95rem;
    position: relative;
    padding-bottom: 0.2rem;
}

.nav-links a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 2px;
    background: var(--accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
    transform: scaleX(1);
}

.nav-toggle {
    display: none;
    background: transparent;
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 0.6rem 0.7rem;
    flex-direction: column;
    gap: 0.3rem;
    cursor: pointer;
}

.nav-toggle-bar {
    width: 22px;
    height: 2px;
    background: var(--chalk);
    display: block;
}

/* Hero */
.hero {
    min-height: calc(100vh - var(--nav-height));
    display: flex;
    align-items: center;
}

.hero-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 3rem;
    align-items: center;
}

.hero-text {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.2em;
    font-size: 0.8rem;
    color: var(--accent-2);
}

.lead {
    font-size: 1.1rem;
    color: var(--chalk);
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 0.6rem;
}

.hero-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.hero-facts {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    font-size: 0.95rem;
    color: var(--chalk-muted);
}

.hero-media {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.image-frame {
    padding: 1.5rem;
    border-radius: var(--radius);
    border: 2px solid var(--line);
    background: rgba(7, 9, 12, 0.7);
    box-shadow: var(--shadow);
}

.image-frame.small {
    padding: 1rem;
}

.contact-illustration-wrap {
    display: flex;
    justify-content: center;
    align-items: center;
}

.contact-illustration-img {
    width: 100%;
    max-width: 220px;
    border-radius: 16px;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.hero-card {
    padding: 1.5rem;
    border-radius: var(--radius);
    border: 2px dashed var(--line);
    background: var(--card);
    box-shadow: var(--shadow);
}

.hero-card-title {
    font-family: 'Kalam', cursive;
    color: var(--chalk);
    margin-bottom: 0.4rem;
}

/* Buttons and links */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.75rem 1.6rem;
    border-radius: 999px;
    border: 2px solid var(--line);
    font-weight: 600;
    font-size: 0.95rem;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    cursor: pointer;
}

.btn.primary {
    background: var(--accent);
    color: #031018;
    border-color: transparent;
    box-shadow: 0 12px 24px rgba(94, 240, 255, 0.25);
}

.btn.ghost {
    background: transparent;
}

.btn:hover,
.btn:focus-visible {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.35);
}

.text-link {
    color: var(--accent);
    font-weight: 600;
}

.text-link:hover,
.text-link:focus-visible {
    color: var(--accent-2);
}

.chip {
    padding: 0.3rem 0.8rem;
    border-radius: 999px;
    border: 1px dashed var(--line);
    font-size: 0.85rem;
    color: var(--chalk-muted);
    background: rgba(255, 255, 255, 0.02);
}

.bullet-list,
.card-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.45rem;
    color: var(--chalk-muted);
}

.bullet-list li,
.card-list li {
    position: relative;
    padding-left: 1.1rem;
}

.bullet-list li::before,
.card-list li::before {
    content: '-';
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* Cards and grids */
.card-grid,
.features-grid,
.mini-grid,
.contact-grid {
    display: grid;
    gap: 2rem;
}

.card-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.experience-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: stretch;
}

.experience-grid .card {
    min-height: 340px;
}

.features-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.mini-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    margin-top: 2.5rem;
}

.card,
.feature-item,
.mini-card,
.contact-card,
.info-card {
    background: var(--card);
    border-radius: var(--radius);
    border: 2px solid var(--line);
    padding: 1.6rem;
    box-shadow: var(--shadow);
}

.card {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.metrics {
    font-weight: 600;
    color: var(--chalk);
}

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

.placeholder-card {
    border-style: dashed;
}

.card-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
    border-radius: 18px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.feature-item {
    text-align: left;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.feature-icon {
    font-size: 2.4rem;
    color: var(--accent);
}

.mini-card {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.mini-image {
    width: 100%;
    max-width: 120px;
}

/* Contact */
.contact-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    align-items: start;
}

.contact-card {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

form {
    display: flex;
    flex-direction: column;
    gap: 1.4rem;
}

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

label {
    font-weight: 600;
    color: var(--chalk);
}

input,
textarea {
    width: 100%;
    padding: 0.9rem 1rem;
    background: rgba(6, 8, 12, 0.9);
    border-radius: 16px;
    border: 1px solid var(--line);
    color: var(--chalk);
    font-family: 'Sora', sans-serif;
}

button {
    font-family: inherit;
    color: inherit;
    background: none;
}

input:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(94, 240, 255, 0.2);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.6rem;
}

.info-card {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.social-links {
    display: flex;
    gap: 1rem;
    font-size: 1.4rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    border-radius: 12px;
    border: 1px solid var(--line);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.social-links a:hover,
.social-links a:focus-visible {
    transform: translateY(-2px);
    border-color: var(--accent);
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 1.5rem 4rem;
    border-top: 1px solid var(--line);
    position: relative;
    z-index: 1;
}

footer p {
    color: var(--chalk-muted);
}

/* Reveal animation */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

/* Responsive */
@media screen and (max-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr;
    }
}

@media screen and (max-width: 900px) {
    :root {
        --nav-height: 68px;
    }

    .site-nav {
        padding: 0 1.2rem;
    }

    .brand-name {
        font-size: 1.2rem;
    }

    .track-toggle {
        min-width: 130px;
    }

    .nav-toggle {
        display: inline-flex;
    }

    .nav-links {
        position: absolute;
        top: calc(100% + 0.6rem);
        right: 1rem;
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
        padding: 1rem 1.2rem;
        background: rgba(12, 15, 20, 0.95);
        border: 1px solid var(--line);
        border-radius: 16px;
        opacity: 0;
        transform: translateY(-10px);
        pointer-events: none;
        transition: opacity 0.2s ease, transform 0.2s ease;
    }

    body.nav-open .nav-links {
        opacity: 1;
        transform: translateY(0);
        pointer-events: auto;
    }

    .hero-actions {
        flex-direction: column;
        align-items: flex-start;
    }

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

    .experience-grid .card {
        min-height: unset;
    }
}

@media screen and (max-width: 600px) {
    section {
        padding: 4rem 1.2rem;
    }

    .card-image {
        height: 160px;
    }

    .brand {
        gap: 0.6rem;
    }

    .track-toggle {
        min-width: 120px;
    }
}