:root {
    --bg: #ffffff;
    --card-bg: #f8fafc;
    --text: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --link: #0284c7;
    --link-hover: #0369a1;
    --warning-bg: #fffbeb;
    --warning-border: #fde68a;
    --warning-text: #92400e;
    --danger-text: #dc2626;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.8;
    font-size: 1.08rem;
    padding: 3.5rem 1.5rem 6rem;
    -webkit-font-smoothing: antialiased;
}

.article-wrapper {
    max-width: 760px;
    margin: 0 auto;
}

/* Header */
.post-header {
    margin-bottom: 2.2rem;
    padding-bottom: 1.2rem;
    border-bottom: 1px solid var(--border);
}

.post-title {
    font-size: 2.2rem;
    font-weight: 800;
    line-height: 1.25;
    margin-bottom: 0.6rem;
    color: #0f172a;
    letter-spacing: -0.025em;
}

.post-date {
    font-size: 0.95rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* Content */
.intro {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #1e293b;
    margin-bottom: 1.8rem;
}

a {
    color: var(--link);
    text-decoration: underline;
    text-underline-offset: 3px;
    font-weight: 500;
    word-break: break-all;
    transition: color 0.15s ease;
}

a:hover {
    color: var(--link-hover);
}

.divider {
    border: 0;
    border-top: 1px solid var(--border);
    margin: 2.2rem 0;
}

.step-section {
    margin-bottom: 2.2rem;
}

.step-section h3 {
    font-size: 1.35rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: #0f172a;
}

.highlight-text {
    margin-bottom: 0.75rem;
    color: #334155;
}

.bullet-list {
    margin-left: 1.6rem;
    margin-top: 0.6rem;
    margin-bottom: 0.9rem;
}

.bullet-list li {
    margin-bottom: 0.6rem;
    color: #1e293b;
}

/* Image & Zoom */
.post-image-container {
    margin: 1.8rem 0;
}

.image-zoom-hint {
    position: relative;
    display: inline-block;
    width: 100%;
    cursor: zoom-in;
}

.guide-image {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px;
    border: 1px solid var(--border);
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.image-zoom-hint:hover .guide-image {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.zoom-badge {
    position: absolute;
    bottom: 12px;
    right: 12px;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(4px);
    color: #fff;
    font-size: 0.8rem;
    font-weight: 600;
    padding: 0.35rem 0.75rem;
    border-radius: 20px;
    pointer-events: none;
    opacity: 0.9;
    transition: opacity 0.2s ease;
}

figcaption {
    font-size: 0.88rem;
    color: var(--text-muted);
    margin-top: 0.6rem;
    text-align: center;
    font-style: italic;
}

/* Lightbox Modal & Wheel Zoom */
.lightbox-modal {
    display: none;
    position: fixed;
    z-index: 99999;
    left: 0;
    top: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(10, 15, 29, 0.92);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    opacity: 0;
    transition: opacity 0.25s ease;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    user-select: none;
}

.lightbox-modal.show {
    display: flex;
    opacity: 1;
}

.lightbox-toolbar {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: rgba(255, 255, 255, 0.12);
    padding: 0.4rem 1rem;
    border-radius: 30px;
    color: #f1f5f9;
    font-size: 0.85rem;
    z-index: 10;
    pointer-events: none;
    backdrop-filter: blur(6px);
}

.zoom-level-badge {
    background: #0284c7;
    color: #fff;
    padding: 0.15rem 0.5rem;
    border-radius: 12px;
    font-weight: 700;
    font-size: 0.8rem;
}

.toolbar-hint {
    color: #cbd5e1;
    font-weight: 500;
}

.lightbox-viewport {
    width: 100vw;
    height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.lightbox-content {
    max-width: 90vw;
    max-height: 80vh;
    object-fit: contain;
    border-radius: 6px;
    box-shadow: 0 12px 48px rgba(0, 0, 0, 0.7);
    transform-origin: center center;
    transition: transform 0.08s ease-out;
    cursor: default;
    will-change: transform;
}

.lightbox-content.can-drag {
    cursor: grab;
}

.lightbox-content.is-dragging {
    cursor: grabbing;
    transition: none;
}

.lightbox-close {
    position: absolute;
    top: 15px;
    right: 20px;
    color: #f1f5f9;
    font-size: 32px;
    font-weight: bold;
    cursor: pointer;
    line-height: 1;
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.12);
    transition: background 0.2s, transform 0.2s;
    z-index: 10;
}

.lightbox-close:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.08);
}

.lightbox-caption {
    margin-top: 10px;
    text-align: center;
    color: #cbd5e1;
    font-size: 0.92rem;
    z-index: 10;
}

/* Warnings & Notes */
.warning-text {
    background: var(--warning-bg);
    border-left: 4px solid #f59e0b;
    border: 1px solid var(--warning-border);
    border-left-width: 4px;
    padding: 0.8rem 1rem;
    border-radius: 6px;
    margin-top: 0.9rem;
    font-size: 1rem;
    color: var(--warning-text);
}

.sub-text {
    color: var(--text-muted);
    font-size: 0.98rem;
    margin-top: 0.5rem;
}

.footer-notes {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 1.2rem;
    font-size: 1.05rem;
    line-height: 1.75;
    background: #f8fafc;
    border: 1px solid var(--border);
    padding: 1.4rem;
    border-radius: 8px;
}

.note-title {
    color: var(--danger-text);
}

@media (max-width: 768px) {
    .toolbar-hint {
        display: none;
    }
    .lightbox-toolbar {
        top: 15px;
    }
}