/* MattBot shared styles */
:root {
    --accent: #3498db;
    --accent-dark: #2980b9;
    --accent-border: #3498db;
    --bg-start: #2c3e50;
    --bg-end: #34495e;
    --card-bg: rgba(255, 255, 255, 0.95);
    --text: #333;
    --text-muted: #555;
    --header-text: #2c3e50;
}

[data-theme="instructions"] {
    --accent: #3498db;
    --accent-dark: #2980b9;
    --accent-border: #3498db;
    --bg-start: #1e3c72;
    --bg-end: #2a5298;
}

[data-theme="construction"] {
    --accent: #f39c12;
    --accent-dark: #e67e22;
    --accent-border: #f39c12;
    --bg-start: #f39c12;
    --bg-end: #e67e22;
}

[data-theme="setup"] {
    --accent: #27ae60;
    --accent-dark: #2ecc71;
    --accent-border: #27ae60;
    --bg-start: #27ae60;
    --bg-end: #2ecc71;
}

[data-theme="operation"] {
    --accent: #e74c3c;
    --accent-dark: #c0392b;
    --accent-border: #e74c3c;
    --bg-start: #e74c3c;
    --bg-end: #c0392b;
}

[data-theme="kaist"] {
    --accent: #7b4397;
    --accent-dark: #5c2d7a;
    --accent-border: #7b4397;
    --bg-start: #5c2d7a;
    --bg-end: #7b4397;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: linear-gradient(135deg, var(--bg-start) 0%, var(--bg-end) 100%);
    min-height: 100vh;
}

/* Sticky site navigation */
.site-nav {
    position: sticky;
    top: 0;
    z-index: 200;
    background: rgba(44, 62, 80, 0.97);
    backdrop-filter: blur(8px);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.2);
}

.site-nav-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0.6rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}

.site-nav-brand {
    color: #ecf0f1;
    font-weight: 600;
    text-decoration: none;
    font-size: 1rem;
    white-space: nowrap;
}

.site-nav-brand:hover {
    color: #fff;
}

.site-nav-links {
    display: flex;
    gap: 0.35rem;
    flex-wrap: wrap;
}

.site-nav-links a {
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
    padding: 0.4rem 0.75rem;
    border-radius: 6px;
    font-size: 0.9rem;
    transition: background 0.2s, color 0.2s;
}

.site-nav-links a:hover,
.site-nav-links a.active {
    background: rgba(255, 255, 255, 0.15);
    color: #fff;
}

.site-nav-links a.active {
    background: var(--accent);
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
}

.container.with-sidebar {
    max-width: 1200px;
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 2rem;
    align-items: start;
}

.container.with-sidebar > aside {
    position: sticky;
    top: 4.5rem;
    align-self: start;
    z-index: 10;
}

.page-layout {
    min-width: 0;
}

.header {
    text-align: center;
    background: var(--card-bg);
    padding: 2.5rem 2rem;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
}

.header h1 {
    color: var(--header-text);
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    font-weight: 300;
}

.header .subtitle {
    color: #7f8c8d;
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

.nav-links {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 0.5rem;
}

.nav-link {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 0.65rem 1.25rem;
    text-decoration: none;
    border-radius: 25px;
    transition: all 0.3s ease;
    font-weight: 500;
    font-size: 0.95rem;
}

.nav-link:hover {
    background: var(--accent-dark);
    transform: translateY(-2px);
}

.nav-link.back {
    background: #95a5a6;
}

.nav-link.back:hover {
    background: #7f8c8d;
}

/* Phase progress (instructions hub) */
.phase-progress {
    display: flex;
    justify-content: center;
    gap: 0;
    margin: 1.5rem 0 0;
    flex-wrap: wrap;
}

.phase-step {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: #f0f3f5;
    color: #7f8c8d;
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
}

.phase-step:first-child {
    border-radius: 25px 0 0 25px;
}

.phase-step:last-child {
    border-radius: 0 25px 25px 0;
}

.phase-step:hover {
    background: #e8ecef;
    color: var(--header-text);
}

.phase-step.active {
    background: var(--accent);
    color: white;
}

.phase-step .num {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

.phase-step.active .num {
    background: rgba(255, 255, 255, 0.3);
}

.section {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
}

.section h2 {
    color: var(--header-text);
    font-size: 1.8rem;
    margin-bottom: 1.25rem;
    border-bottom: 3px solid var(--accent-border);
    padding-bottom: 0.5rem;
}

.section h3 {
    color: var(--accent-dark);
    font-size: 1.35rem;
    margin: 1.5rem 0 0.75rem;
}

.section h4 {
    color: var(--header-text);
    font-size: 1.1rem;
    margin: 1rem 0 0.5rem;
}

.section p,
.section li {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 0.85rem;
}

.section ul,
.section ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.pin-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    font-size: 0.95rem;
    border: 2px solid #b0b8c4;
}

.pin-table th,
.pin-table td {
    border: 1px solid #b0b8c4;
    padding: 0.6rem 0.75rem;
    text-align: left;
}

.pin-table thead th {
    border-bottom: 2px solid #b0b8c4;
}

.pin-table th {
    background: #f0f3f5;
    color: var(--header-text);
    font-weight: 600;
}

.pin-table tbody tr:nth-child(even) {
    background: #fafbfc;
}

/* Table of contents sidebar */
.toc-sidebar {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    max-height: calc(100vh - 6rem);
    overflow-y: auto;
}

.toc-sidebar h3 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #7f8c8d;
    margin-bottom: 0.75rem;
}

.toc-sidebar ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.toc-sidebar li {
    margin-bottom: 0.25rem;
}

.toc-sidebar a {
    display: block;
    padding: 0.35rem 0.5rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.88rem;
    border-radius: 6px;
    border-left: 3px solid transparent;
    transition: all 0.15s;
}

.toc-sidebar a:hover {
    background: #f0f3f5;
    color: var(--header-text);
}

.toc-sidebar a.active {
    border-left-color: var(--accent);
    background: #f0f3f5;
    color: var(--header-text);
    font-weight: 600;
}

.toc-sidebar .toc-h3 a {
    padding-left: 1rem;
    font-size: 0.82rem;
}

/* Mobile TOC toggle */
.toc-toggle {
    display: none;
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    margin-bottom: 1rem;
}

/* Collapsible panels */
.collapsible {
    border: 1px solid #e0e6ed;
    border-radius: 10px;
    margin-bottom: 0.75rem;
    overflow: hidden;
    background: #fafbfc;
}

.collapsible-trigger {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 1rem 1.25rem;
    background: #f8f9fa;
    border: none;
    cursor: pointer;
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--header-text);
    text-align: left;
    transition: background 0.2s;
}

.collapsible-trigger:hover {
    background: #eef1f4;
}

.collapsible-trigger .chevron {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    transition: transform 0.25s;
    color: var(--accent);
}

.collapsible.open .collapsible-trigger .chevron {
    transform: rotate(180deg);
}

.collapsible-panel {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s ease;
}

.collapsible.open .collapsible-panel {
    max-height: 5000px;
}

.collapsible-content {
    padding: 0 1.25rem 1.25rem;
}

/* Step cards */
.step-card {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 10px;
    margin: 1rem 0;
    border-left: 5px solid var(--accent);
}

.step-number {
    background: var(--accent);
    color: white;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1rem;
    margin-bottom: 0.75rem;
}

/* Code blocks with copy */
.code-wrap {
    position: relative;
    margin: 1rem 0;
}

.code-block {
    background: #2c3e50;
    color: #ecf0f1;
    padding: 1rem 3rem 1rem 1rem;
    border-radius: 8px;
    font-family: 'Consolas', 'Courier New', monospace;
    font-size: 0.9rem;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-all;
}

.copy-btn {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    background: rgba(255, 255, 255, 0.15);
    color: #ecf0f1;
    border: 1px solid rgba(255, 255, 255, 0.25);
    padding: 0.3rem 0.6rem;
    border-radius: 5px;
    font-size: 0.75rem;
    cursor: pointer;
    transition: background 0.2s;
}

.copy-btn:hover {
    background: rgba(255, 255, 255, 0.25);
}

.copy-btn.copied {
    background: #27ae60;
    border-color: #27ae60;
}

.tip,
.warning,
.success {
    padding: 1rem 1.25rem;
    border-radius: 8px;
    margin: 1rem 0;
}

.tip {
    background: #d1ecf1;
    border: 1px solid #bee5eb;
}

.tip strong {
    color: #0c5460;
}

.warning {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
}

.warning strong {
    color: #e17055;
}

.success {
    background: #d4edda;
    border: 1px solid #c3e6cb;
}

.success strong {
    color: #155724;
}

/* Grids */
.components-grid,
.repos-grid,
.instructions-grid,
.controls-grid,
.config-grid,
.parts-grid,
.req-grid {
    display: grid;
    gap: 1.25rem;
    margin-top: 1.5rem;
}

.components-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.repos-grid {
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.instructions-grid {
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

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

.req-grid {
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.component-card {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
    padding: 1.25rem;
    border-radius: 10px;
    color: white;
    transition: transform 0.3s ease;
}

.component-card:hover {
    transform: translateY(-4px);
}

.component-card h3 {
    color: #fff;
    font-size: 1.15rem;
    margin-bottom: 0.5rem;
}

.component-card p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.95rem;
    margin: 0;
}

.repo-card {
    background: linear-gradient(135deg, #27ae60, #2ecc71);
    padding: 1.25rem;
    border-radius: 10px;
    text-align: center;
    transition: transform 0.3s ease;
}

.repo-card.hidden {
    display: none;
}

.repo-card:hover {
    transform: translateY(-4px);
}

.repo-card h3 {
    color: white;
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.repo-card p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.repo-link {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    padding: 0.6rem 1.2rem;
    text-decoration: none;
    border-radius: 25px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.repo-link:hover {
    background: rgba(255, 255, 255, 0.35);
}

.repo-search {
    width: 100%;
    max-width: 400px;
    margin: 1rem auto 0;
    display: block;
    padding: 0.65rem 1rem;
    border: 2px solid #e0e6ed;
    border-radius: 25px;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

.repo-search:focus {
    border-color: var(--accent);
}

.instruction-card {
    background: var(--card-bg);
    padding: 1.75rem;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.instruction-card:hover {
    transform: translateY(-4px);
}

.instruction-card h3 {
    color: var(--header-text);
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}

.card-link {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    border-radius: 25px;
    font-weight: 600;
    transition: transform 0.2s;
}

.card-link:hover {
    transform: scale(1.03);
}

.instruction-card.construction .card-link {
    background: linear-gradient(135deg, #f39c12, #e67e22);
}

.instruction-card.setup .card-link {
    background: linear-gradient(135deg, #27ae60, #2ecc71);
}

.instruction-card.operation .card-link {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
}

.control-card,
.config-card,
.part-card,
.req-item {
    background: #f8f9fa;
    padding: 1.25rem;
    border-radius: 10px;
    border-left: 4px solid var(--accent);
}

.req-item h4,
.control-card h4,
.config-card h4,
.part-card h4 {
    color: var(--header-text);
    margin-bottom: 0.5rem;
}

.link-card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.25rem;
    margin-top: 1rem;
}

.link-card {
    display: block;
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 12px;
    text-decoration: none;
    border: 2px solid #e8ecef;
    transition: all 0.25s;
}

.link-card:hover {
    border-color: var(--accent);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.link-card h3 {
    color: var(--header-text);
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.link-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin: 0;
}

.link-card .arrow {
    color: var(--accent);
    font-weight: 600;
    margin-top: 0.75rem;
    display: inline-block;
}

/* Images */
.section-image,
.img-responsive {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 1rem auto;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
    cursor: zoom-in;
}

.img-pair {
    display: flex;
    gap: 1%;
    flex-wrap: wrap;
    align-items: flex-start;
    margin: 1rem 0;
}

.img-pair img {
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    cursor: zoom-in;
}

.img-pair .img-small {
    width: 19%;
    min-width: 80px;
}

.img-pair .img-large {
    width: 79%;
    flex: 1;
    min-width: 200px;
}

.video-wrap {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 10px;
    margin-top: 1.5rem;
}

.video-wrap iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

/* Lightbox */
.lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 1000;
    background: rgba(0, 0, 0, 0.9);
    align-items: center;
    justify-content: center;
    padding: 2rem;
    cursor: zoom-out;
}

.lightbox.open {
    display: flex;
}

.lightbox img {
    max-width: 95%;
    max-height: 95%;
    border-radius: 8px;
    object-fit: contain;
}

/* Back to top */
.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--accent);
    color: white;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    font-size: 1.4rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.25);
    transition: all 0.3s ease;
    opacity: 0;
    visibility: hidden;
    z-index: 150;
    border: none;
    cursor: pointer;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--accent-dark);
    transform: translateY(-3px);
}

.quick-ref {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1rem 0;
}

.quick-ref-item {
    background: #f0f3f5;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
}

.quick-ref-item strong {
    display: block;
    color: var(--header-text);
    margin-bottom: 0.25rem;
}

/* Subtle collaborator portal link (operation page footer) */
.collaborator-note {
    text-align: center;
    font-size: 0.92rem;
    color: #95a5a6;
    margin: 0;
}

.collaborator-note a {
    color: var(--text-muted);
    text-decoration: underline;
    text-underline-offset: 2px;
}

.collaborator-note a:hover {
    color: var(--header-text);
}

/* KAIST updates log */
.update-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.update-badge {
    display: inline-block;
    padding: 0.2rem 0.55rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.update-badge.software {
    background: #d1ecf1;
    color: #0c5460;
}

.update-badge.hardware {
    background: #fff3cd;
    color: #856404;
}

.update-badge.script {
    background: #e8daef;
    color: #5b2c6f;
}

.update-badge.other {
    background: #e8ecef;
    color: #495057;
}

.update-date {
    font-size: 0.88rem;
    color: #7f8c8d;
    font-weight: 500;
}

.collapsible-trigger .update-title {
    flex: 1;
}

.collapsible.update-item .collapsible-trigger {
    flex-wrap: wrap;
}

.add-update-note {
    background: #f0f3f5;
    border: 1px dashed #b0b8c4;
    border-radius: 8px;
    padding: 1rem 1.25rem;
    font-size: 0.92rem;
    color: var(--text-muted);
    margin-bottom: 1.25rem;
}

.add-update-note code {
    font-size: 0.85rem;
    background: #e8ecef;
    padding: 0.1rem 0.35rem;
    border-radius: 3px;
}

.updates-divider {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin: 2rem 0 1.25rem;
    color: #95a5a6;
    font-size: 0.88rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.updates-divider::before,
.updates-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: #d5dbe3;
}

.updates-empty {
    text-align: center;
    font-size: 0.92rem;
    color: #95a5a6;
    font-style: italic;
    margin: 0;
    padding: 0.5rem 0 0.25rem;
}

/* Development / Production workflow toggle */
.workflow-toggle-bar {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
    background: var(--card-bg);
    padding: 1rem 1.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
}

.workflow-toggle-label {
    font-weight: 600;
    color: var(--header-text);
    font-size: 0.95rem;
    margin-right: 0.25rem;
}

.workflow-toggle-btn {
    padding: 0.55rem 1.25rem;
    border: 2px solid #e0e6ed;
    background: #f8f9fa;
    color: var(--text-muted);
    border-radius: 25px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.workflow-toggle-btn:hover {
    border-color: var(--accent);
    color: var(--header-text);
}

.workflow-toggle-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: white;
}

@media (max-width: 900px) {
    .container.with-sidebar {
        grid-template-columns: 1fr;
    }

    .container.with-sidebar > aside {
        position: static;
    }

    .toc-sidebar {
        position: static;
        max-height: none;
        display: none;
    }

    .toc-sidebar.mobile-open {
        display: block;
    }

    .toc-toggle {
        display: block;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .header h1 {
        font-size: 1.75rem;
    }

    .site-nav-inner {
        padding: 0.5rem 1rem;
    }

    .components-grid,
    .repos-grid,
    .instructions-grid {
        grid-template-columns: 1fr;
    }
}