/* =========================================================
   Zakhiyah Arsal — Case Study
   Visual language: clean, minimal, monochrome
   ========================================================= */

:root {
    --bg: #ffffff;
    --surface: #f5f5f3;
    --surface-2: #ededeb;
    --text: #111111;
    --muted: #6d6d6d;
    --line: #ddddda;
    --accent: #111111;
    --max-width: 1180px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.6;
    transition: background-color .3s ease, color .3s ease;
}

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

.site-header {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    height: 88px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--line);
}

.logo {
    font-size: 13px;
    font-weight: 700;
    letter-spacing: .12em;
}

.nav {
    display: flex;
    gap: 28px;
}

.nav a {
    font-size: 13px;
    color: var(--muted);
    transition: color .2s ease;
}

.nav a:hover {
    color: var(--text);
}

.theme-toggle {
    border: 1px solid var(--line);
    background: transparent;
    color: var(--text);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 16px;
}

.case-hero {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    padding: 72px 0 84px;
}

.breadcrumb {
    display: flex;
    gap: 10px;
    color: var(--muted);
    font-size: 12px;
    margin-bottom: 72px;
}

.breadcrumb a:hover {
    color: var(--text);
}

.eyebrow {
    margin: 0 0 16px;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: .16em;
    color: var(--muted);
}

.case-hero h1 {
    margin: 0;
    font-size: clamp(48px, 7vw, 92px);
    line-height: .98;
    letter-spacing: -.055em;
    font-weight: 700;
}

.case-hero h1 span {
    color: var(--muted);
}

.hero-description {
    max-width: 650px;
    margin: 34px 0 52px;
    font-size: 20px;
    line-height: 1.55;
    color: var(--muted);
}

.hero-meta {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.hero-meta div {
    padding: 22px 24px 22px 0;
}

.hero-meta div + div {
    padding-left: 24px;
    border-left: 1px solid var(--line);
}

.hero-meta span,
.tech-list span {
    display: block;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: .14em;
    color: var(--muted);
    margin-bottom: 6px;
}

.hero-meta strong {
    font-size: 13px;
    font-weight: 500;
}

/* .project-visual {
    width: 100%;
    padding: 70px max(24px, calc((100% - var(--max-width)) / 2));
    background: var(--surface);
} */

.device-frame {
    max-width: 980px;
    margin: auto;
    padding: 18px;
    border: 1px solid var(--line);
    background: #1a1a1a;
    border-radius: 18px;
}

.screen-placeholder {
    min-height: 470px;
    background: #f0f0ed;
    color: #111;
    border-radius: 8px;
    padding: 22px;
}

.screen-top {
    display: flex;
    justify-content: space-between;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: .1em;
    border-bottom: 1px solid #ccc;
    padding-bottom: 14px;
}

.screen-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 80px;
    min-height: 390px;
}

.tank {
    width: 150px;
    height: 300px;
    border: 4px solid #333;
    border-radius: 10px 10px 16px 16px;
    overflow: hidden;
    position: relative;
    background: #fff;
}

.tank::before {
    content: "100%\A\A 75%\A\A 50%\A\A 25%\A\A 0%";
    white-space: pre;
    position: absolute;
    left: -48px;
    top: 22px;
    line-height: 56px;
    font-size: 10px;
    color: #555;
}

.tank-fill {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 64%;
    background: #8b9ca4;
}

.process-values {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
}

.process-values div {
    width: 180px;
    background: #fff;
    padding: 18px;
    border: 1px solid #ccc;
}

.process-values small {
    display: block;
    font-size: 9px;
    color: #777;
    margin-bottom: 4px;
}

.process-values strong {
    display: block;
    font-size: 24px;
}

.process-values em {
    font-size: 10px;
    color: #777;
    font-style: normal;
}

.image-caption {
    max-width: 980px;
    margin: 14px auto 0;
    font-size: 11px;
    color: var(--muted);
}

.content-section {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    padding: 110px 0;
    border-bottom: 1px solid var(--line);
}

.two-column {
    display: grid;
    grid-template-columns: 30% 1fr;
    gap: 60px;
}

.section-label span {
    font-size: 11px;
    color: var(--muted);
}

.section-label h2 {
    margin: 8px 0 0;
    font-size: 30px;
    letter-spacing: -.035em;
}

.section-content {
    max-width: 760px;
}

.section-content p {
    color: var(--muted);
    margin-top: 0;
}

.section-content .lead {
    font-size: 22px;
    line-height: 1.55;
    color: var(--text);
    margin-bottom: 28px;
}

.highlight-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    margin-top: 44px;
    border-top: 1px solid var(--line);
}

.highlight {
    padding: 25px 25px 20px 0;
    border-bottom: 1px solid var(--line);
}

.highlight:nth-child(even) {
    padding-left: 25px;
    border-left: 1px solid var(--line);
}

.highlight span {
    font-size: 10px;
    color: var(--muted);
}

.highlight strong {
    display: block;
    margin: 8px 0 4px;
    font-size: 14px;
}

.highlight p {
    font-size: 13px;
    margin: 0;
}

.architecture-section {
    padding: 110px 24px;
    background: var(--surface);
}

.section-heading {
    max-width: var(--max-width);
    margin: auto auto 65px;
}

.section-heading h2 {
    margin: 0 0 14px;
    font-size: clamp(36px, 5vw, 58px);
    letter-spacing: -.05em;
}

.section-heading > p:last-child {
    max-width: 560px;
    color: var(--muted);
}

.architecture {
    max-width: 950px;
    margin: auto;
    text-align: center;
}

.arch-node {
    background: var(--bg);
    border: 1px solid var(--line);
    padding: 22px;
    min-width: 250px;
}

.arch-node span {
    display: block;
    font-size: 9px;
    letter-spacing: .14em;
    font-weight: 700;
    color: var(--muted);
    margin-bottom: 6px;
}

.arch-node strong {
    display: block;
    font-size: 18px;
}

.arch-node small {
    display: block;
    margin-top: 5px;
    color: var(--muted);
    font-size: 11px;
}

.arch-node.controller {
    border: 2px solid var(--text);
}

.arch-line {
    height: 42px;
    width: 1px;
    background: var(--line);
    margin: auto;
}

.arch-branches {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.arch-branch {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.arch-line.vertical {
    height: 36px;
}

.tech-list {
    border-top: 1px solid var(--line);
}

.tech-list div {
    display: grid;
    grid-template-columns: 180px 1fr;
    padding: 18px 0;
    border-bottom: 1px solid var(--line);
}

.tech-list strong {
    font-size: 14px;
    font-weight: 500;
}

.feature-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0 50px;
}

.feature-list article {
    display: grid;
    grid-template-columns: 36px 1fr;
    gap: 16px;
    padding: 25px 0;
    border-top: 1px solid var(--line);
}

.feature-list article > span {
    font-size: 10px;
    color: var(--muted);
}

.feature-list h3 {
    margin: 0 0 6px;
    font-size: 15px;
}

.feature-list p {
    font-size: 13px;
    margin: 0;
}

.engineering-note {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    padding: 110px 0;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: end;
}

.engineering-note h2 {
    font-size: clamp(38px, 5vw, 60px);
    line-height: 1;
    letter-spacing: -.055em;
    margin: 0;
}

.engineering-note > p {
    margin: 0;
    max-width: 500px;
    color: var(--muted);
}

.case-navigation {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    padding: 35px 0 80px;
    border-top: 1px solid var(--line);
    display: flex;
    justify-content: space-between;
}

.case-navigation a {
    display: flex;
    gap: 16px;
    align-items: center;
}

.case-navigation a.next {
    text-align: right;
}

.case-navigation span {
    font-size: 25px;
}

.case-navigation small {
    display: block;
    font-size: 9px;
    letter-spacing: .13em;
    color: var(--muted);
}

.case-navigation strong {
    font-size: 14px;
}

.site-footer {
    width: min(var(--max-width), calc(100% - 48px));
    margin: auto;
    padding: 35px 0 55px;
    border-top: 1px solid var(--line);
    display: flex;
    justify-content: space-between;
    align-items: end;
}

.site-footer strong {
    font-size: 12px;
    letter-spacing: .12em;
}

.site-footer p {
    margin: 5px 0 0;
    color: var(--muted);
    font-size: 12px;
}

.footer-links {
    display: flex;
    gap: 22px;
}

.footer-links a {
    font-size: 12px;
    color: var(--muted);
}

.dark-mode {
    --bg: #121212;
    --surface: #1a1a1a;
    --surface-2: #222;
    --text: #f2f2f0;
    --muted: #999;
    --line: #303030;
    --accent: #f2f2f0;
}

.dark-mode .device-frame {
    background: #050505;
}

.dark-mode .screen-placeholder {
    background: #e9e9e6;
    color: #111;
}

@media (max-width: 800px) {
    .site-header {
        height: 72px;
    }

    .nav {
        display: none;
    }

    .case-hero {
        padding: 45px 0 60px;
    }

    .breadcrumb {
        margin-bottom: 48px;
    }

    .case-hero h1 {
        font-size: 52px;
    }

    .hero-description {
        font-size: 17px;
        margin: 25px 0 38px;
    }

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

    .hero-meta div,
    .hero-meta div + div {
        padding: 17px 0;
        border-left: 0;
    }

    .hero-meta div + div {
        border-top: 1px solid var(--line);
    }

    .screen-placeholder {
        min-height: 360px;
    }

    .screen-content {
        gap: 30px;
        min-height: 290px;
    }

    .tank {
        width: 90px;
        height: 210px;
    }

    .process-values {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .process-values div {
        width: 145px;
        padding: 10px;
    }

    .process-values strong {
        font-size: 17px;
    }

    .two-column,
    .engineering-note {
        grid-template-columns: 1fr;
        gap: 35px;
    }

    .content-section,
    .engineering-note {
        padding: 75px 0;
    }

    .highlight-grid,
    .feature-list {
        grid-template-columns: 1fr;
    }

    .highlight:nth-child(even) {
        padding-left: 0;
        border-left: 0;
    }

    .arch-branches {
        grid-template-columns: 1fr;
    }

    .case-navigation {
        gap: 25px;
        flex-direction: column;
    }

    .case-navigation a.next {
        text-align: left;
        justify-content: flex-end;
    }

    .site-footer {
        align-items: flex-start;
        flex-direction: column;
        gap: 25px;
    }
}

/* =========================
Project Image Gallery
========================= */

.project-visual {
width: 100%;
margin: 60px 0;
}

.image-gallery {
position: relative;
width: 100%;
max-width: 1000px;
margin: 0 auto;
display: flex;
align-items: center;
justify-content: center;
}

.gallery-track {
width: 100%;
overflow: hidden;
border-radius: 12px;
}

.gallery-slide {
display: none;
width: 100%;
text-align: center;
}

.gallery-slide.active {
display: block;
}

.gallery-slide img {
display: block;
width: 100%;
max-height: 560px;
object-fit: contain;
border-radius: 12px;
}

/* Caption */

.image-caption {
margin-top: 14px;
font-size: 14px;
color: #666;
}

/* Navigation buttons */

.gallery-btn {
position: absolute;
top: 50%;
transform: translateY(-50%);
z-index: 2;


width: 42px;
height: 42px;

border: none;
border-radius: 50%;

background: rgba(0, 0, 0, 0.55);
color: white;

font-size: 22px;
cursor: pointer;

display: flex;
align-items: center;
justify-content: center;

transition: background 0.2s ease,
            transform 0.2s ease;

}

.gallery-btn:hover {
background: rgba(0, 0, 0, 0.8);
}

.gallery-prev {
left: 18px;
}

.gallery-next {
right: 18px;
}

/* Dots */

.gallery-dots {
display: flex;
justify-content: center;
gap: 8px;
margin-top: 18px;
}

.gallery-dot {
width: 8px;
height: 8px;

padding: 0;
border: none;
border-radius: 50%;

background: #bbb;
cursor: pointer;

transition: transform 0.2s ease;


}

.gallery-dot.active {
transform: scale(1.4);
background: #333;
}

/* Mobile */

@media (max-width: 600px) {


.gallery-btn {
    width: 36px;
    height: 36px;
    font-size: 18px;
}

.gallery-prev {
    left: 10px;
}

.gallery-next {
    right: 10px;
}

.image-caption {
    font-size: 13px;
}


}