/* =========================================================
   Brittner.NET – Referenzen / Case Studies
   Ergänzung zum V3-Design
   ========================================================= */

.bn3-ref-hero,
.bn3-ref-single-hero {
    position: relative;
    overflow: hidden;
    padding: calc(var(--bn3-header-height) + 105px) 0 104px;
    background:
        radial-gradient(circle at 86% 18%, rgba(35,128,201,.22), transparent 31%),
        radial-gradient(circle at 8% 88%, rgba(80,161,223,.10), transparent 28%),
        linear-gradient(155deg, #07111d 0%, #0b1726 48%, #10263b 100%);
}

.bn3-ref-hero::after,
.bn3-ref-single-hero::after {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    opacity: .12;
    background-image:
        linear-gradient(rgba(255,255,255,.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.08) 1px, transparent 1px);
    background-size: 48px 48px;
    mask-image: linear-gradient(to bottom, rgba(0,0,0,.7), transparent 90%);
}

.bn3-ref-hero-grid,
.bn3-ref-single-hero-grid {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(350px, .85fr);
    gap: 92px;
    align-items: end;
}

.bn3-ref-hero h1,
.bn3-ref-single-title h1 {
    max-width: 830px;
    margin: 0;
    color: #fff;
    font-size: clamp(3.2rem, 6.3vw, 6.6rem);
    line-height: .94;
    letter-spacing: -.065em;
}

.bn3-ref-hero h1 span {
    color: #6bb5e8;
}

.bn3-ref-hero-copy > p,
.bn3-ref-single-title > p {
    margin: 0;
    color: rgba(255,255,255,.66);
    font-size: 1.08rem;
    line-height: 1.8;
}

.bn3-ref-hero-facts {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-top: 32px;
}

.bn3-ref-hero-facts span {
    padding: 17px 18px;
    border: 1px solid rgba(255,255,255,.10);
    border-radius: 14px;
    background: rgba(255,255,255,.035);
    color: rgba(255,255,255,.46);
    font-size: .72rem;
    line-height: 1.45;
}

.bn3-ref-hero-facts strong {
    display: block;
    margin-bottom: 3px;
    color: #fff;
    font-size: .95rem;
}

/* Intro */
.bn3-ref-intro {
    padding: 72px 0;
    border-bottom: 1px solid var(--bn3-line);
    background: #fff;
}

.bn3-ref-intro-grid {
    display: grid;
    grid-template-columns: minmax(220px, .45fr) minmax(0, 1.55fr);
    gap: 90px;
    align-items: start;
}

.bn3-ref-intro-grid > p {
    max-width: 850px;
    margin: 0;
    color: var(--bn3-text);
    font-size: clamp(1.2rem, 2vw, 1.65rem);
    line-height: 1.6;
    letter-spacing: -.018em;
}

/* Archive */
.bn3-ref-archive {
    padding: 110px 0 120px;
    background: var(--bn3-surface-soft);
}

.bn3-ref-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 32px;
}

.bn3-ref-card {
    overflow: hidden;
    border: 1px solid var(--bn3-line);
    border-radius: 24px;
    background: #fff;
    box-shadow: 0 18px 54px rgba(7,17,29,.055);
    transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease;
}

.bn3-ref-card:first-child {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: minmax(0, 1.18fr) minmax(380px, .82fr);
}

.bn3-ref-card:hover {
    transform: translateY(-4px);
    border-color: rgba(23,105,170,.24);
    box-shadow: 0 28px 76px rgba(7,17,29,.10);
}

.bn3-ref-card-visual {
    display: block;
    padding: 34px;
    background:
        radial-gradient(circle at 70% 30%, rgba(80,161,223,.20), transparent 34%),
        linear-gradient(145deg, #0b1726, #142c44);
}

.bn3-ref-card:nth-child(2n) .bn3-ref-card-visual {
    background:
        radial-gradient(circle at 28% 72%, rgba(80,161,223,.18), transparent 34%),
        linear-gradient(145deg, #102033, #07111d);
}

.bn3-ref-card-copy {
    padding: 38px 38px 42px;
}

.bn3-ref-card:first-child .bn3-ref-card-copy {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 54px;
}

.bn3-ref-card-copy h2 {
    margin: 13px 0 16px;
    color: var(--bn3-ink);
    font-size: clamp(1.7rem, 3vw, 2.7rem);
    line-height: 1.05;
    letter-spacing: -.04em;
}

.bn3-ref-card-copy h2 a {
    color: inherit;
}

.bn3-ref-card-copy p {
    margin: 0 0 25px;
    color: var(--bn3-text);
    font-size: .98rem;
    line-height: 1.75;
}

.bn3-ref-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 7px;
}

.bn3-ref-meta span {
    display: inline-flex;
    padding: 6px 9px;
    border: 1px solid var(--bn3-line);
    border-radius: 999px;
    color: var(--bn3-muted);
    font-size: .63rem;
    font-weight: 800;
    letter-spacing: .06em;
    text-transform: uppercase;
}

.bn3-ref-card-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--bn3-blue-600);
    font-size: .86rem;
    font-weight: 800;
}

.bn3-ref-card-link span {
    transition: transform .2s ease;
}

.bn3-ref-card-link:hover span {
    transform: translateX(4px);
}

/* Browser preview */
.bn3-ref-browser {
    overflow: hidden;
    width: 100%;
    border: 1px solid rgba(255,255,255,.14);
    border-radius: 18px;
    background: #0a1624;
    box-shadow: 0 28px 70px rgba(0,0,0,.25);
}

.bn3-ref-browser-bar {
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 14px;
    align-items: center;
    min-height: 44px;
    padding: 0 14px;
    border-bottom: 1px solid rgba(255,255,255,.08);
    background: rgba(255,255,255,.035);
    color: rgba(255,255,255,.42);
    font-size: .64rem;
    font-weight: 700;
}

.bn3-ref-browser-dots {
    display: flex;
    gap: 5px;
}

.bn3-ref-browser-dots i {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: rgba(255,255,255,.25);
}

.bn3-ref-browser-lock {
    width: 7px;
    height: 9px;
    border: 1px solid rgba(255,255,255,.24);
    border-radius: 2px;
}

.bn3-ref-browser-screen {
    position: relative;
    overflow: hidden;
    aspect-ratio: 16 / 10;
    background: #0d1d2e;
}

.bn3-ref-browser-screen img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top center;
}

.bn3-ref-preview-placeholder {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: clamp(26px, 5vw, 52px);
    background:
        radial-gradient(circle at 78% 20%, rgba(80,161,223,.22), transparent 30%),
        linear-gradient(145deg, #10263c, #08131f);
}

.bn3-ref-preview-placeholder > span {
    margin-bottom: 10px;
    color: #6bb5e8;
    font-size: .62rem;
    font-weight: 800;
    letter-spacing: .13em;
    text-transform: uppercase;
}

.bn3-ref-preview-placeholder > strong {
    max-width: 580px;
    color: #fff;
    font-size: clamp(1.35rem, 3vw, 3.2rem);
    line-height: 1;
    letter-spacing: -.05em;
}

.bn3-ref-preview-placeholder > p {
    max-width: 650px;
    margin: 18px 0 0;
    color: rgba(255,255,255,.55);
    line-height: 1.7;
}

.bn3-ref-preview-placeholder > b {
    position: absolute;
    right: 28px;
    bottom: 24px;
    color: rgba(255,255,255,.40);
    font-size: .68rem;
    font-weight: 700;
}

.bn3-ref-preview-lines {
    display: flex;
    flex-direction: column;
    gap: 7px;
    width: 55%;
    margin-top: 24px;
}

.bn3-ref-preview-lines i {
    height: 5px;
    border-radius: 999px;
    background: rgba(255,255,255,.10);
}

.bn3-ref-preview-lines i:nth-child(2) { width: 76%; }
.bn3-ref-preview-lines i:nth-child(3) { width: 42%; }

/* Principle */
.bn3-ref-principle {
    padding: 110px 0;
    background: #fff;
}

.bn3-ref-principle-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(350px, .85fr);
    gap: 90px;
    align-items: center;
}

.bn3-ref-principle h2,
.bn3-ref-overview h2,
.bn3-ref-next h2 {
    margin: 0;
    color: var(--bn3-ink);
    font-size: clamp(2.3rem, 4.5vw, 4.4rem);
    line-height: 1.02;
    letter-spacing: -.05em;
}

.bn3-ref-principle-grid > div:last-child p {
    margin: 0 0 24px;
    color: var(--bn3-text);
    font-size: 1.05rem;
    line-height: 1.8;
}

/* Single */
.bn3-ref-back {
    position: relative;
    z-index: 2;
    display: inline-flex;
    align-items: center;
    gap: 9px;
    margin-bottom: 56px;
    color: rgba(255,255,255,.50);
    font-size: .76rem;
    font-weight: 700;
}

.bn3-ref-back:hover {
    color: #fff;
}

.bn3-ref-single-title > p {
    max-width: 750px;
    margin-top: 26px;
}

.bn3-ref-meta-light span {
    border-color: rgba(255,255,255,.14);
    color: rgba(255,255,255,.55);
}

.bn3-ref-single-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 34px;
}

.bn3-ref-single-summary {
    display: grid;
    grid-template-columns: 105px 1fr;
    gap: 0 20px;
    align-self: end;
    padding: 26px;
    border: 1px solid rgba(255,255,255,.11);
    border-radius: 20px;
    background: rgba(255,255,255,.035);
    backdrop-filter: blur(12px);
}

.bn3-ref-single-summary span,
.bn3-ref-single-summary strong {
    padding: 12px 0;
    border-bottom: 1px solid rgba(255,255,255,.08);
}

.bn3-ref-single-summary span:nth-last-child(-n+2),
.bn3-ref-single-summary strong:nth-last-child(-n+2) {
    border-bottom: 0;
}

.bn3-ref-single-summary span {
    color: rgba(255,255,255,.38);
    font-size: .65rem;
    font-weight: 800;
    letter-spacing: .08em;
    text-transform: uppercase;
}

.bn3-ref-single-summary strong {
    color: rgba(255,255,255,.82);
    font-size: .82rem;
    font-weight: 700;
}

.bn3-ref-showcase {
    padding: 90px 0 40px;
    background: var(--bn3-surface-soft);
}

.bn3-ref-browser-large {
    border-color: rgba(7,17,29,.16);
    border-radius: 22px;
    box-shadow: 0 30px 90px rgba(7,17,29,.14);
}

.bn3-ref-browser-large .bn3-ref-browser-bar {
    min-height: 50px;
    background: #0d1b2a;
}

.bn3-ref-browser-large .bn3-ref-browser-screen {
    aspect-ratio: 16 / 8.6;
}

.bn3-ref-image-hint {
    margin: 18px 0 0;
    color: var(--bn3-muted);
    font-size: .72rem;
    text-align: center;
}

.bn3-ref-overview {
    padding: 100px 0 115px;
    background: var(--bn3-surface-soft);
}

.bn3-ref-overview-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(330px, .65fr);
    gap: 100px;
    align-items: start;
}

.bn3-ref-overview h2 {
    max-width: 730px;
    margin-bottom: 30px;
}

.bn3-ref-editor-content {
    max-width: 780px;
    color: var(--bn3-text);
    font-size: 1.04rem;
    line-height: 1.9;
}

.bn3-ref-editor-content p:last-child {
    margin-bottom: 0;
}

.bn3-ref-project-data {
    overflow: hidden;
    border: 1px solid var(--bn3-line);
    border-radius: 20px;
    background: #fff;
    box-shadow: var(--bn3-shadow-soft);
}

.bn3-ref-data-block {
    padding: 28px;
}

.bn3-ref-data-block + .bn3-ref-data-block {
    border-top: 1px solid var(--bn3-line);
}

.bn3-ref-data-block > span {
    display: block;
    margin-bottom: 17px;
    color: var(--bn3-blue-600);
    font-size: .66rem;
    font-weight: 800;
    letter-spacing: .12em;
    text-transform: uppercase;
}

.bn3-ref-data-block ul {
    display: grid;
    gap: 11px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.bn3-ref-data-block li {
    position: relative;
    padding-left: 18px;
    color: var(--bn3-text);
    font-size: .88rem;
    line-height: 1.55;
}

.bn3-ref-data-block li::before {
    content: "";
    position: absolute;
    top: .7em;
    left: 0;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--bn3-blue-500);
}

.bn3-ref-tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 7px;
}

.bn3-ref-tech-tags i {
    padding: 7px 9px;
    border: 1px solid var(--bn3-line);
    border-radius: 999px;
    background: var(--bn3-surface-soft);
    color: var(--bn3-text);
    font-size: .68rem;
    font-style: normal;
    font-weight: 700;
}

/* Story */
.bn3-ref-story {
    padding: 105px 0;
    background: #081522;
}

.bn3-ref-story-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-top: 1px solid rgba(255,255,255,.11);
    border-bottom: 1px solid rgba(255,255,255,.11);
}

.bn3-ref-story article {
    position: relative;
    min-height: 420px;
    padding: 42px 34px;
}

.bn3-ref-story article + article {
    border-left: 1px solid rgba(255,255,255,.11);
}

.bn3-ref-story-index {
    display: block;
    margin-bottom: 72px;
    color: rgba(107,181,232,.72);
    font-size: .72rem;
    font-weight: 800;
    letter-spacing: .12em;
}

.bn3-ref-story small {
    display: block;
    margin-bottom: 10px;
    color: rgba(255,255,255,.34);
    font-size: .62rem;
    font-weight: 800;
    letter-spacing: .12em;
    text-transform: uppercase;
}

.bn3-ref-story h3 {
    margin: 0 0 18px;
    color: #fff;
    font-size: 1.55rem;
    line-height: 1.1;
    letter-spacing: -.035em;
}

.bn3-ref-story p {
    margin: 0;
    color: rgba(255,255,255,.56);
    font-size: .91rem;
    line-height: 1.75;
}

/* Next */
.bn3-ref-next {
    padding: 110px 0;
    background: #fff;
}

.bn3-ref-next-head {
    max-width: 760px;
    margin-bottom: 48px;
}

.bn3-ref-next-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
}

.bn3-ref-next-card {
    position: relative;
    display: flex;
    flex-direction: column;
    min-height: 220px;
    padding: 30px;
    border: 1px solid var(--bn3-line);
    border-radius: 20px;
    background: var(--bn3-surface-soft);
    transition: background .2s ease, transform .2s ease, border-color .2s ease;
}

.bn3-ref-next-card:hover {
    transform: translateY(-3px);
    border-color: rgba(23,105,170,.22);
    background: #fff;
}

.bn3-ref-next-card > span {
    margin-bottom: 20px;
    color: var(--bn3-blue-600);
    font-size: .65rem;
    font-weight: 800;
    letter-spacing: .10em;
    text-transform: uppercase;
}

.bn3-ref-next-card > strong {
    max-width: 80%;
    color: var(--bn3-ink);
    font-size: 1.65rem;
    line-height: 1.1;
    letter-spacing: -.035em;
}

.bn3-ref-next-card > small {
    margin-top: auto;
    color: var(--bn3-muted);
}

.bn3-ref-next-card > i {
    position: absolute;
    right: 28px;
    bottom: 28px;
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: var(--bn3-navy-900);
    color: #fff;
    font-style: normal;
}

.bn3-ref-empty {
    padding: 70px;
    border: 1px solid var(--bn3-line);
    border-radius: 22px;
    background: #fff;
    text-align: center;
}

/* Responsive */
@media (max-width: 1050px) {
    .bn3-ref-hero-grid,
    .bn3-ref-single-hero-grid,
    .bn3-ref-principle-grid,
    .bn3-ref-overview-grid {
        gap: 56px;
    }

    .bn3-ref-card:first-child {
        grid-template-columns: 1fr;
    }

    .bn3-ref-card:first-child .bn3-ref-card-copy {
        padding: 38px;
    }
}

@media (max-width: 820px) {
    .bn3-ref-hero,
    .bn3-ref-single-hero {
        padding-top: calc(var(--bn3-header-height) + 72px);
        padding-bottom: 72px;
    }

    .bn3-ref-hero-grid,
    .bn3-ref-single-hero-grid,
    .bn3-ref-intro-grid,
    .bn3-ref-principle-grid,
    .bn3-ref-overview-grid {
        grid-template-columns: 1fr;
        gap: 36px;
    }

    .bn3-ref-hero h1,
    .bn3-ref-single-title h1 {
        font-size: clamp(3rem, 12vw, 5rem);
    }

    .bn3-ref-grid,
    .bn3-ref-story-grid,
    .bn3-ref-next-grid {
        grid-template-columns: 1fr;
    }

    .bn3-ref-card:first-child {
        grid-column: auto;
    }

    .bn3-ref-story article {
        min-height: 0;
    }

    .bn3-ref-story article + article {
        border-top: 1px solid rgba(255,255,255,.11);
        border-left: 0;
    }

    .bn3-ref-story-index {
        margin-bottom: 40px;
    }

    .bn3-ref-single-summary {
        max-width: 520px;
    }
}

@media (max-width: 560px) {
    .bn3-ref-hero-facts {
        grid-template-columns: 1fr;
    }

    .bn3-ref-archive,
    .bn3-ref-principle,
    .bn3-ref-overview,
    .bn3-ref-story,
    .bn3-ref-next {
        padding-top: 78px;
        padding-bottom: 78px;
    }

    .bn3-ref-card-visual {
        padding: 18px;
    }

    .bn3-ref-card-copy,
    .bn3-ref-card:first-child .bn3-ref-card-copy {
        padding: 28px 24px 30px;
    }

    .bn3-ref-browser-bar {
        grid-template-columns: auto 1fr;
    }

    .bn3-ref-browser-lock {
        display: none;
    }

    .bn3-ref-preview-placeholder {
        padding: 24px;
    }

    .bn3-ref-preview-placeholder > b {
        right: 20px;
        bottom: 18px;
    }

    .bn3-ref-single-actions {
        flex-direction: column;
    }

    .bn3-ref-single-actions .bn3-btn {
        width: 100%;
        justify-content: center;
    }

    .bn3-ref-single-summary {
        grid-template-columns: 84px 1fr;
        padding: 20px;
    }

    .bn3-ref-story article {
        padding: 34px 24px;
    }

    .bn3-ref-next-card {
        min-height: 190px;
        padding: 25px;
    }
}