/* =================================================
   1. ROOT VARIABLES
================================================= */

:root {
    /* colors */
    --color-bg: #0B0B0F; /* fast schwarz */
    --color-text: #E5E7EB; /* soft weiß */
    --text-light: #9CA3AF;
    --color-muted: #8B5CF6; /* entsättigtes Lila */
    --color-accent: #A855F7; /* klares Lila */
    --color-accent-secondary: #c99cf3; /* Komplement: Cyan */
    --color-border: #1F1F2E;

    /* typography */
    --font-main: 'Inter', sans-serif;

    /* layout */
    --container-width: 1100px;
    --grid-gap: 20px;
    --radius: 12px;

    /* animation */
    --transition: 0.35s;

    /* gradients */
    --gradient-accent: linear-gradient(
        135deg,
        #A855F7,
        #22D3EE
    );

    --gradient-glow: radial-gradient(
        circle at 50% 50%,
        rgba(168, 85, 247, 0.25),
        transparent 70%
    );
}

html {
    scroll-behavior: smooth;
}

/* section divider lines */
#about,
#portfolio-grid,
#contact {
    position: relative;
    padding-top: 80px;
}

#about::before,
#portfolio-grid::before,
#contact::before {
    content: "";
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 1px;
    background: linear-gradient(
        to right,
        transparent,
        rgba(168, 85, 247, 0.35),
        transparent
    );
}

/* =================================================
   2. RESET
================================================= */

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

body {
    font-family: var(--font-main);
    background: var(--color-bg);
    color: var(--color-text);
    font-weight: 400;
    letter-spacing: -0.01em;
}

h1,
h2 {
    font-weight: 600;
    letter-spacing: -0.02em;
}

h3 {
    font-weight: 500;
}

p {
    font-weight: 400;
    line-height: 1.7;
}

/* =================================================
   3. LAYOUT
================================================= */

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: auto;
    padding: 0 20px;
}

/* =================================================
   4. HEADER
================================================= */

header {
    background-color: #0B0B0F;
    position: sticky;
    top: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 40px 10%;
}

.logo h1 {
    font-weight: 300;
    letter-spacing: 2px;
}

.logo span {
    font-size: 14px;
    color: var(--color-muted);
}

/* =================================================
   5. NAVIGATION
================================================= */

nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
}

nav a {
    text-decoration: none;
    color: var(--color-text);
    font-weight: 500;
    transition: color 0.3s ease;
}

nav a.active {
    color: var(--color-accent);
}

/* mobile nav icons default */
.fa-solid.fa-bars,
.fa-solid.fa-xmark {
    display: none;
}

/* =================================================
   6. HERO
================================================= */

.hero {
    text-align: center;
    margin: 140px auto;
    max-width: 700px;
}

.hero h1 {
    background: linear-gradient(
        to right,
        #e8e8e8,
        #A855F7
    );
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-sub {
    color: var(--color-muted);
    font-size: 1.1rem;
    margin-bottom: 30px;
}

.hero-cta {
    margin-top: 20px;
}

/* buttons */
.btn {
    display: inline-block;
    padding: 12px 20px;
    margin: 5px;
    border-radius: 8px;
    text-decoration: none;
    font-size: 0.95rem;
    transition: 0.2s;
}

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

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

.btn.secondary {
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    color: var(--color-muted);
}

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

/* =================================================
   7. WHAT I DO
================================================= */

.what {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin: 120px auto;
    max-width: 1200px;
    flex-wrap: wrap;
}

.card {
    flex: 1;
    min-width: 220px;
    padding: 20px;
    text-align: center;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.card h3 {
    margin-bottom: 10px;
    color: var(--color-text);
}

.card p {
    color: var(--color-text);
    font-size: 0.95rem;
}

/* =================================================
   8. ABOUT
================================================= */

#about {
    padding: 80px 0;
}

.row {
    display: flex;
    gap: 60px;
    align-items: flex-start;
    flex-wrap: wrap;
}

.about-col-1 {
    flex: 1;
    min-width: 250px;
}

.about-col-1 img {
    width: 100%;
    border-radius: var(--radius);
}

.about-col-2 {
    flex: 2;
    min-width: 300px;
    color: var(--text-light);
}

.text {
    margin-top: 40px;
}

.section-break {
    border: none;
    height: 1px;
    width: 100%;
    margin: 30px 0;
    background-color: var(--color-border);
}

.tab-titles {
    display: flex;
    margin: 20px 0 40px;
}

.tab-links {
    margin-right: 50px;
    font-size: 18px;
    font-weight: 500;
    cursor: pointer;
    position: relative;
}

.tab-links::after {
    content: '';
    width: 0;
    height: 3px;
    background: var(--color-accent);
    position: absolute;
    left: 0;
    bottom: -8px;
    transition: 0.5s;
}

.tab-links.active-link::after {
    width: 50%;
}

.tab-contents {
    display: none;
}

.tab-contents.active-tab {
    display: block;
}

.tab-contents ul li {
    list-style: none;
    margin: 10px 0;
}

.tab-contents ul li span {
    color: var(--color-muted);
    font-size: 14px;
}

/* =================================================
   9. PORTFOLIO GRID
================================================= */

#portfolio-grid {
    width: 80%;
    margin: 120px auto;
    display: flex;
    flex-direction: column;
    gap: 40px;
}

#portfolio-grid .tile:nth-child(even) {
    flex-direction: row-reverse;
}

/* =================================================
   10. TILE LAYOUT
================================================= */

.tile {
    display: flex;
    height: 400px;
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s, box-shadow 0.3s;
}

.tile-image {
    position: relative;
    width: 50%;
    height: 100%;
}

.tile-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.4s;
}

.overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        to top,
        rgba(0, 0, 0, 0.8),
        transparent
    );
    transition: opacity 0.3s;
}

.tile-content {
    width: 50%;
    padding: 30px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.tile-content h3 {
    margin-bottom: 10px;
    font-size: 1.4rem;
    color: var(--color-text);
    text-align: center;
}

.tile-content p {
    color: var(--color-text);
    font-size: 0.95rem;
    text-align: center;
}

/* hover */
.tile:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.tile:hover .overlay {
    opacity: 1;
    background: linear-gradient(
        to top,
        rgba(168, 85, 247, 0.4),
        transparent
    );
}

.tile:hover img {
    transform: scale(1.03);
}

/* =================================================
   11. FOOTER
================================================= */

footer {
    width: 80%;
    margin: 80px auto 40px;
    padding: 20px 30px;
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.02);
    backdrop-filter: blur(10px);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

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

.footer-links {
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-links a {
    text-decoration: none;
    color: var(--text-light);
    font-size: 0.9rem;
    transition: color 0.3s ease;
}

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

.footer-links .divider {
    color: var(--color-border);
}

/* =================================================
   12. CONTACT
================================================= */

#contact {
    padding: 120px 0;
}

.contact-container {
    width: 80%;
    margin: 0 auto;
    display: flex;
    gap: 60px;
    align-items: flex-start;
    flex-wrap: wrap;
}

/* left = form */
.contact-form {
    flex: 1;
    min-width: 320px;
}

.contact-form form {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* right = info */
.contact-info {
    flex: 1;
    min-width: 260px;
}

.contact-info h2 {
    font-size: 2.2rem;
    margin-bottom: 20px;
    color: var(--color-text);
}

.contact-info p {
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.6;
}

/* socials */
.social-icons {
    display: flex;
    gap: 16px;
    margin-top: 20px;
}

.social-icons a {
    font-size: 1.5rem;
    color: var(--color-muted);
    transition: transform 0.3s ease, color 0.3s ease;
}

.social-icons a:hover {
    color: var(--color-accent);
    transform: translateY(-3px);
}

/* form inputs */
form input,
form textarea {
    width: 100%;
    border: 1px solid rgba(255, 255, 255, 0.08);
    outline: none;
    background: rgba(255, 255, 255, 0.03);
    padding: 16px 18px;
    color: var(--color-text);
    font-size: 1rem;
    border-radius: 12px;
    font-family: var(--font-main);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

form textarea {
    resize: vertical;
    min-height: 160px;
}

form input::placeholder,
form textarea::placeholder {
    color: var(--text-light);
}

form input:focus,
form textarea:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(168, 85, 247, 0.15);
}

/* button */
.btn2 {
    align-self: flex-start;
    background: var(--color-accent);
    color: #fff;
    border: none;
    cursor: pointer;
    padding: 14px 24px;
    border-radius: 10px;
    transition: transform 0.2s ease, background 0.3s ease;
}

.btn2:hover {
    background: var(--color-accent-secondary);
    transform: translateY(-2px);
}

/* status */
#status {
    margin-top: 12px;
    font-size: 0.95rem;
    color: var(--text-light);
}

#status.success {
    color: #7ee787;
}

#status.error {
    color: #ff7b72;
}

/* =================================================
   13. PROJECT DETAIL PAGE
================================================= */

#backToTop {
    position: fixed;
    right: 24px;
    bottom: 24px;
    width: 52px;
    height: 52px;
    border: none;
    border-radius: 50%;
    background: rgba(168, 85, 247, 0.9);
    color: white;
    font-size: 1.4rem;
    cursor: pointer;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease, background 0.3s ease;
    z-index: 1200;
}

#backToTop.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

#backToTop:hover {
    background: var(--color-accent-secondary);
}

.project-detail-page header {
    position: relative;
    top: unset;
}

.project-page {
    width: min(1100px, 90%);
    margin: 0 auto;
    padding: 40px 0 100px;
}

.project-hero {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 40px;
    align-items: center;
    margin: 40px 0 120px;
}

.project-eyebrow {
    color: var(--color-muted);
    font-size: 0.85rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.project-hero h1,
.project-hero h2 {
    font-size: clamp(1.8rem, 3.5vw, 2.8rem);
    line-height: 1.15;
}

.project-lead {
    color: var(--text-light);
    font-size: 1.08rem;
    line-height: 1.7;
    max-width: 60ch;
}

.project-meta {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
    margin-top: 30px;
}

.meta-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
    border-radius: 12px;
    padding: 18px;
}

.meta-card span {
    display: block;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-muted);
    margin-bottom: 8px;
}

.meta-card p {
    color: var(--color-text);
    font-size: 0.95rem;
    line-height: 1.5;
}

.project-hero-media img {
    width: 100%;
    display: block;
    border-radius: 18px;
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
}

.project-section {
    position: relative;
    margin-bottom: 110px;
    padding-top: 10px;
}

.project-section::before {
    content: "";
    position: absolute;
    top: -45px;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 1px;
    background: linear-gradient(
        to right,
        transparent,
        rgba(168, 85, 247, 0.35),
        transparent
    );
}

.project-section:first-of-type::before {
    display: none;
}

.section-heading {
    margin-bottom: 24px;
}

.section-label {
    color: var(--color-muted);
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 8px;
}

.section-heading h2 {
    font-size: 2rem;
    color: var(--color-text);
}

.project-grid {
    display: grid;
    gap: 24px;
    align-items: start;
}

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

.project-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
    border-radius: 16px;
    padding: 28px;
    backdrop-filter: blur(12px);
}

.project-card h3 {
    color: var(--color-text);
    margin-bottom: 12px;
    font-size: 1.2rem;
}

.project-card p {
    color: var(--text-light);
    line-height: 1.8;
}

.media-card {
    padding: 18px;
}

.media-card img,
.media-card video {
    width: 100%;
    display: block;
    border-radius: 12px;
}

.project-actions {
    margin-top: 24px;
    margin-bottom: 10px;
}

.github-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 18px;
    border-radius: 10px;
    text-decoration: none;
    color: var(--color-text);
    border: 1px solid rgba(255, 255, 255, 0.08);
    background: rgba(255, 255, 255, 0.03);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    transition:
        transform 0.2s ease,
        border-color 0.3s ease,
        color 0.3s ease,
        background 0.3s ease;
}

.github-link:hover {
    transform: translateY(-2px);
    border-color: var(--color-accent);
    color: var(--color-accent);
    background: rgba(255, 255, 255, 0.05);
}

.github-link i {
    font-size: 1.05rem;
}

/* storyboard + poster layout */
.project-media-block {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
    border-radius: 16px;
    padding: 18px;
    overflow: hidden;
}

.project-media-block img {
    width: 100%;
    display: block;
    border-radius: 12px;
    object-fit: contain;
    max-height: 620px;
    background: rgba(255, 255, 255, 0.02);
}

.media-caption {
    margin-top: 12px;
    color: var(--text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

.project-grid.two-col .project-media-block {
    height: 100%;
}

.flow-list {
    padding-left: 20px;
    color: var(--text-light);
    line-height: 1.9;
}

.resource-links {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
}

.resource-links a {
    display: inline-block;
    padding: 12px 18px;
    border-radius: 10px;
    text-decoration: none;
    color: var(--color-text);
    border: 1px solid rgba(255, 255, 255, 0.08);
    background: rgba(255, 255, 255, 0.02);
    transition: transform 0.2s ease, border-color 0.3s ease, color 0.3s ease;
}

.resource-links a:hover {
    transform: translateY(-2px);
    border-color: var(--color-accent);
    color: var(--color-accent);
}

/* =================================================
   14. RESPONSIVE
================================================= */

/* tablet */
@media (max-width: 900px) {
    .project-hero {
        grid-template-columns: 1fr;
        margin-bottom: 90px;
    }

    .project-meta {
        grid-template-columns: 1fr;
    }

    .project-grid.two-col {
        grid-template-columns: 1fr;
    }

    .project-grid.three-col {
        grid-template-columns: 1fr;
    }

    .section-heading h2 {
        font-size: 1.7rem;
    }

    .project-media-block img {
        max-height: none;
    }

    .card {
        flex-direction: column;
    }

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

    .tile {
        aspect-ratio: 4 / 3;
    }

    .site-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
}

/* contact mobile */
@media (max-width: 800px) {
    .contact-container {
        flex-direction: column-reverse;
        gap: 40px;
    }

    .btn2 {
        width: 100%;
        text-align: center;
    }
}

/* mobile */
@media (max-width: 600px) {
    /* allgemein */
    header {
        padding: 20px 6%;
        gap: 16px;
    }

    .logo h1 {
        font-size: 1.2rem;
        letter-spacing: 1px;
    }

    .logo span {
        font-size: 0.78rem;
        display: block;
        margin-top: 4px;
    }

    /* burger / mobile nav */
    .fa-solid.fa-bars,
    .fa-solid.fa-xmark {
        display: block;
        font-size: 24px;
        cursor: pointer;
        color: var(--color-text);
        z-index: 1002;
    }

    #menu-icon {
        display: block;
    }

    nav ul {
        display: flex;
        flex-direction: column;
        align-items: flex-start;
        gap: 0;
        background: #12121a;
        position: fixed;
        top: 0;
        right: -220px;
        width: 220px;
        height: 100vh;
        padding: 80px 24px 24px;
        z-index: 1001;
        transition: right 0.35s ease;
        box-shadow: -10px 0 30px rgba(0, 0, 0, 0.35);
    }

    nav ul li {
        display: block;
        width: 100%;
        margin: 0 0 22px 0;
    }

    nav ul li a {
        display: block;
        width: 100%;
        font-size: 1rem;
    }

    #close-icon {
        position: absolute;
        top: 22px;
        right: 22px;
        display: block;
    }

    /* hero */
    .hero {
        margin: 90px auto 70px;
        padding: 0 20px;
    }

    .hero h1 {
        font-size: 2rem;
        line-height: 1.2;
    }

    .hero-sub {
        font-size: 1rem;
        margin-top: 16px;
    }

    .hero-cta {
        display: flex;
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
        margin-top: 28px;
    }

    .btn {
        width: 100%;
        text-align: center;
        margin: 0;
    }

    /* what i do */
    .what {
        margin: 70px auto;
        padding: 0 20px;
        gap: 16px;
    }

    .card {
        min-width: 100%;
    }

    /* about */
    #about {
        padding: 70px 0;
    }

    .row {
        flex-direction: column;
        gap: 32px;
    }

    .about-col-1,
    .about-col-2 {
        width: 100%;
        min-width: 100%;
    }

    .about-col-1 {
        display: flex;
        justify-content: center;
    }

    .about-col-1 img {
        width: 100%;
        max-width: 320px;
        height: auto;
        border-radius: 14px;
        display: block;
    }

    .text {
        margin-top: 0;
    }

    .tab-titles {
        flex-wrap: wrap;
        gap: 18px;
        margin: 20px 0 28px;
    }

    .tab-links {
        margin-right: 0;
        font-size: 1rem;
    }

    /* portfolio grid */
    #portfolio-grid {
        width: 92%;
        margin: 80px auto;
        gap: 24px;
    }

    .tile,
    #portfolio-grid .tile:nth-child(even) {
        flex-direction: column;
        height: auto;
    }

    .tile-image {
        width: 100%;
        height: 200px;
    }

    .tile-content {
        width: 100%;
        min-height: 120px;
        padding: 20px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        text-align: center;
    }

    .tile-content h3 {
        font-size: 1.1rem;
        line-height: 1.35;
        margin-bottom: 6px;
    }

    .tile-content p {
        font-size: 0.9rem;
        margin: 0;
    }

    /* contact */
    #contact {
        padding: 80px 0;
    }

    .contact-left,
    .contact-right {
        min-width: 100%;
    }

    .contact-right form {
        margin-top: 10px;
    }

    .btn2 {
        width: 100%;
        text-align: center;
        align-self: stretch;
    }

    /* footer */
    footer {
        width: 92%;
        padding: 18px 16px;
        margin: 60px auto 30px;
    }

    .footer-content {
        flex-direction: column;
        align-items: flex-start;
    }

    .footer-links {
        flex-wrap: wrap;
    }

    /* back to top */
    #backToTop {
        right: 16px;
        bottom: 16px;
        width: 46px;
        height: 46px;
        font-size: 1.2rem;
    }
}

/* =================================================
   USABILITY HEIZUNG – CLEAN CASE STUDY REBUILD
================================================= */

.project-case-page {
    width: 80%;
    margin: 0 auto;
    padding: 40px 0 100px;
}

.project-case-hero {
    display: grid;
    grid-template-columns: 1.05fr 1fr;
    gap: 56px;
    align-items: center;
    margin: 30px 0 110px;
}

.project-hero__content {
    display: flex;
    flex-direction: column;
    gap: 26px;
}

.eyebrow {
    display: inline-block;
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-muted);
}

.project-title {
    font-size: clamp(2.2rem, 4vw, 3.6rem);
    line-height: 1.08;
    color: var(--color-text);
    margin: 0 0 10px;
    max-width: 12ch;
}

.project-description {
    max-width: 62ch;
    color: var(--text-light);
    font-size: 1.05rem;
    line-height: 1.8;
}

.badge-list {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.badge,
.visual-chip {
    display: inline-flex;
    align-items: center;
    padding: 10px 14px;
    border-radius: 999px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.07);
    color: var(--color-text);
    font-size: 0.9rem;
}

.project-hero__visual {
    position: relative;
    overflow: hidden;
    border-radius: 20px;
    border: 1px solid rgba(255,255,255,0.08);
    box-shadow: 0 20px 50px rgba(0,0,0,0.35);
}

.hero-image {
    width: 100%;
    height: 100%;
    min-height: 460px;
    object-fit: cover;
    display: block;
}

.visual-overlay {
    position: absolute;
    left: 20px;
    right: 20px;
    bottom: 20px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

/* ===== Section Intro ===== */

.case-study-section {
    position: relative;
    padding-top: 50px;
}

.case-study-section::before {
    content: "";
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 1px;
    background: linear-gradient(
        to right,
        transparent,
        rgba(168,85,247,0.35),
        transparent
    );
}

.section-header {
    max-width: 760px;
    margin-bottom: 42px;
}

.section-title {
    font-size: clamp(1.8rem, 3vw, 2.6rem);
    color: var(--color-text);
    margin: 10px 0 14px;
}

.section-intro {
    color: var(--text-light);
    line-height: 1.8;
}

/* ===== Main Layout ===== */

.case-layout {
    display: grid;
    grid-template-columns: 360px minmax(0, 1fr);
    gap: 64px;
    align-items: start;
}

/* ===== Side Menu ===== */

.case-menu {
    position: sticky;
    top: 110px;
    padding-right: 10px;
}

.case-menu__title {
    margin-bottom: 22px;
    font-size: 0.9rem;
    color: var(--color-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.case-menu__list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.case-trigger {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 0;
    background: transparent;
    border: none;
    border-bottom: 1px solid rgba(255,255,255,0.06);
    color: var(--text-light);
    cursor: pointer;
    text-align: left;
    transition: color 0.25s ease, transform 0.25s ease;
}

.case-trigger:hover {
    color: var(--color-text);
    transform: translateX(4px);
}

.case-trigger.is-active {
    color: var(--color-text);
}

.case-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    flex-shrink: 0;
    transition: background 0.25s ease, box-shadow 0.25s ease;
}

.case-trigger.is-active .case-dot {
    background: var(--color-accent);
    box-shadow: 0 0 0 6px rgba(168,85,247,0.12);
}

.case-trigger__label {
    font-size: 1.02rem;
    font-weight: 500;
}

/* ===== Right Content ===== */

.case-content {
    min-width: 0;
}

.case-panel {
    display: none;
}

.case-panel.is-active {
    display: block;
}

.panel-shell {
    padding: 0;
    background: transparent;
    border: none;
    box-shadow: none;
}

.panel-header {
    margin-bottom: 28px;
}

.panel-title {
    font-size: 2rem;
    color: var(--color-text);
    margin: 8px 0 12px;
}

.panel-body {
    padding: 0;
}

.panel-grid {
    display: grid;
    grid-template-columns: 1.45fr 0.9fr;
    gap: 44px;
}

.panel-stack,
.aside-stack {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.panel-card,
.highlight-box {
    background: transparent;
    border: none;
    box-shadow: none;
    padding: 0;
}

.panel-card h4 {
    color: var(--color-text);
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.panel-card p,
.panel-card li,
.highlight-box {
    color: var(--text-light);
    line-height: 1.85;
}

.panel-card ul {
    padding-left: 18px;
}

.highlight-box {
    padding-left: 16px;
    border-left: 2px solid rgba(168,85,247,0.45);
}

.highlight-box strong {
    display: block;
    margin-bottom: 10px;
    color: var(--color-text);
    font-size: 1rem;
}

.back-link {
    display: inline-block;
    margin-top: 30px;
    color: var(--color-accent);
    text-decoration: none;
    font-weight: 500;
}

.back-link:hover {
    text-decoration: underline;
}

/* ===== Responsive ===== */

@media (max-width: 1100px) {
    .project-case-page {
        width: 88%;
    }

    .case-layout {
        grid-template-columns: 300px minmax(0, 1fr);
        gap: 40px;
    }

    .panel-grid {
        gap: 28px;
    }
}

@media (max-width: 900px) {
    .project-case-page {
        width: 92%;
        padding: 24px 0 70px;
    }

    .project-case-hero,
    .case-layout,
    .panel-grid {
        grid-template-columns: 1fr;
    }

    .project-case-hero {
        gap: 30px;
        margin-bottom: 70px;
    }

    .case-menu {
        position: static;
        padding-right: 0;
        margin-bottom: 10px;
    }

    .case-menu__list {
        gap: 0;
    }

    .hero-image {
        min-height: 300px;
    }

    .panel-title {
        font-size: 1.6rem;
    }
}

@media (max-width: 600px) {
    .project-case-page {
        width: 92%;
    }

    .project-title {
        font-size: 2rem;
        max-width: none;
    }

    .project-description,
    .section-intro,
    .panel-card p,
    .panel-card li,
    .highlight-box {
        font-size: 0.98rem;
        line-height: 1.75;
    }

    .badge,
    .visual-chip {
        font-size: 0.82rem;
        padding: 8px 12px;
    }

    .case-trigger__label {
        font-size: 0.95rem;
    }
}