/* ============================================
   Case Studies Page V2 - Styles
   参考：成功案例 — 客户故事.html
   ============================================ */

/* --- CSS Variables --- */
:root {
    --cs-bg: #f5f4f1;
    --cs-card-bg: #ffffff;
    --cs-text-primary: #09090b;
    --cs-text-secondary: #52525b;
    --cs-text-tertiary: #a1a1aa;
    --cs-text-muted: #d4d4d8;
    --cs-accent: #10b981;
    --cs-accent-light: #ecfdf5;
    --cs-accent-border: #a7f3d0;
    --cs-border: rgba(0,0,0,0.06);
    --cs-border-light: rgba(0,0,0,0.05);
    --cs-radius: 16px;
    --cs-radius-lg: 24px;
    --cs-radius-xl: 28px;
    --cs-container: 1280px;
    --cs-font-mono: 'JetBrains Mono', monospace;
}

/* --- Base --- */
.cs-page {
    color: var(--cs-text-primary);
    -webkit-font-smoothing: antialiased;
}
.cs-container {
    max-width: var(--cs-container);
    margin-left: auto;
    margin-right: auto;
    padding-left: 24px;
    padding-right: 24px;
}

/* --- Animations --- */
@keyframes cs-fade-up {
    from { opacity: 0; transform: translateY(24px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes cs-marquee {
    from { transform: translateX(0); }
    to { transform: translateX(-50%); }
}
@keyframes cs-pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(0.85); }
}
.cs-animate-fade-up {
    animation: cs-fade-up 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* ============================================
   HERO SECTION
   ============================================ */
.cs-hero {
    padding-top: 64px;
    padding-bottom: 40px;
}
.cs-hero-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
    align-items: flex-end;
}
@media (min-width: 768px) {
    .cs-hero-grid {
        grid-template-columns: 1fr 1fr;
        gap: 40px;
    }
}
.cs-hero-left {
    animation: cs-fade-up 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
    animation-delay: 0.05s;
}
.cs-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--cs-accent-light);
    border: 1px solid var(--cs-accent-border);
    color: #047857;
    font-size: 12px;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 99px;
    margin-bottom: 20px;
}
.cs-badge-dot {
    display: inline-block;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--cs-accent);
    animation: cs-pulse-dot 2s ease-in-out infinite;
}
.cs-hero-title {
    font-size: 48px;
    font-weight: 800;
    letter-spacing: -0.05em;
    line-height: 1;
    color: var(--cs-text-primary);
    margin-bottom: 20px;
}
@media (min-width: 768px) {
    .cs-hero-title { font-size: 60px; }
}
.cs-text-muted {
    color: #feb801;
}
.cs-hero-desc {
    font-size: 16px;
    color: var(--cs-text-tertiary);
    line-height: 1.625;
    max-width: 48ch;
}

/* Hero Metrics */
.cs-hero-right {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    animation: cs-fade-up 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
    animation-delay: 0.15s;
}
.cs-metric-card {
    background: var(--cs-card-bg);
    border: 1px solid var(--cs-border);
    border-radius: var(--cs-radius);
    padding: 20px;
}
.cs-metric-value {
    font-family: var(--cs-font-mono);
    font-size: 30px;
    font-weight: 700;
    color: var(--cs-text-primary);
    margin-bottom: 4px;
}
.cs-metric-label {
    font-size: 12px;
    color: var(--cs-text-tertiary);
    line-height: 1.375;
}

/* ============================================
   MARQUEE BAND
   ============================================ */
.cs-marquee {
    overflow: hidden;
    border-top: 1px solid var(--cs-border-light);
    border-bottom: 1px solid var(--cs-border-light);
    padding: 12px 0;
    background: rgba(255,255,255,0.5);
    margin-bottom: 40px;
}
.cs-marquee-track {
    display: flex;
    width: max-content;
    animation: cs-marquee 28s linear infinite;
}
.cs-marquee-slide {
    display: flex;
    align-items: center;
    gap: 48px;
    padding: 0 32px;
    font-size: 12px;
    font-weight: 500;
    color: var(--cs-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    white-space: nowrap;
}
.cs-marquee-dot {
    color: var(--cs-text-muted);
}

/* ============================================
   FILTER BAR
   ============================================ */
.cs-filter {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 40px;
}
.cs-filter-row {
    display: flex;
    align-items: center;
    gap: 12px;
}
.cs-filter-label {
    font-size: 13px;
    font-weight: 600;
    color: var(--cs-text-tertiary);
    white-space: nowrap;
    min-width: 32px;
}
.cs-filter-pills {
    display: flex;
    align-items: center;
    gap: 8px;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}
.cs-filter-pills::-webkit-scrollbar { display: none; }

.cs-pill {
    display: inline-block;
    font-size: 14px;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 99px;
    border: 1px solid rgba(0,0,0,0.1);
    background: transparent;
    color: var(--cs-text-secondary);
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
    white-space: nowrap;
}
.cs-pill:hover {
    background: rgba(0,0,0,0.06);
}
.cs-pill.active {
    background: var(--cs-text-primary);
    color: #ffffff;
    border-color: var(--cs-text-primary);
}

/* Mobile filter: hidden by default, show on mobile */
.cs-filter-mobile {
    display: none;
}
.cs-filter-desktop {
    display: flex;
    flex-direction: column;
    grid-gap: 12px;
}
.cs-select-row {
    display: flex;
    align-items: center;
    gap: 12px;
}
.cs-select {
    flex: 1;
    appearance: none;
    -webkit-appearance: none;
    font-size: 14px;
    font-weight: 500;
    padding: 10px 36px 10px 14px;
    border-radius: 10px;
    border: 1px solid rgba(0,0,0,0.1);
    background: var(--cs-card-bg);
    color: var(--cs-text-primary);
    cursor: pointer;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2371717a' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    transition: border-color 0.2s;
}
.cs-select:focus {
    outline: none;
    border-color: var(--cs-text-primary);
}

@media (max-width: 768px) {
    .cs-filter-desktop { display: none; }
    .cs-filter-mobile { display: flex; flex-direction: column; gap: 12px; }
}

/* ============================================
   FEATURED CASE
   ============================================ */
.cs-featured {
    margin-bottom: 32px;
    animation: cs-fade-up 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
    animation-delay: 0.2s;
}
.cs-featured-card {
    display: block;
    position: relative;
    border-radius: var(--cs-radius-lg);
    overflow: hidden;
    cursor: pointer;
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1),
                box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.cs-featured-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 40px 80px -20px rgba(0,0,0,0.18);
}
.cs-featured-img-wrap {
    position: relative;
    height: 420px;
    overflow: hidden;
}
@media (min-width: 768px) {
    .cs-featured-img-wrap { height: 500px; }
}
.cs-featured-img-wrap .card-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.cs-featured-card:hover .card-img {
    transform: translateY(0);
}
.cs-featured-img-wrap .card-img,
.cs-card-img-wrap .card-img {
    display: block;
    width: 100%;
    height: auto;
    min-height: 100%;
    transform: translateY(0);
}
.cs-featured-img-wrap .cover-img,
.cs-card-img-wrap .cover-img {
    position: absolute;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    z-index: 3;
    opacity: 1;
    transition: 0.3s ease;
    object-fit: cover;
}
.cs-featured-img-wrap:hover .cover-img,
.cs-card-img-wrap:hover .cover-img {
    opacity: 0;
}
.cs-featured-gradient,
.cs-featured-content,
.cs-card-img-gradient,
.cs-card-img-tag {
    z-index: 4;
}
.cs-featured-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(to right, rgba(9,9,11,0.8), rgba(9,9,11,0.4), transparent);
}
.cs-featured-content {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: flex-end;
    padding: 32px;
}
@media (min-width: 768px) {
    .cs-featured-content { padding: 48px; }
}
.cs-featured-inner {
    max-width: 576px;
}
.cs-featured-tags {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 16px;
}
.cs-featured-title {
    font-size: 30px;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: -0.025em;
    line-height: 1.25;
    margin-bottom: 12px;
}
@media (min-width: 768px) {
    .cs-featured-title { font-size: 36px; }
}
.cs-featured-desc {
    font-size: 14px;
    color: rgba(255,255,255,0.6);
    line-height: 1.625;
    margin-bottom: 24px;
    max-width: 52ch;
}
.cs-featured-metrics {
    display: flex;
    align-items: center;
    gap: 32px;
    margin-bottom: 24px;
}
.cs-featured-metric-val {
    font-family: var(--cs-font-mono);
    font-size: 24px;
    font-weight: 600;
    color: #ffffff;
}
.cs-featured-metric-label {
    font-size: 12px;
    color: rgba(255,255,255,0.5);
    margin-top: 2px;
}
.cs-featured-divider {
    width: 1px;
    height: 32px;
    background: rgba(255,255,255,0.1);
}
.cs-featured-footer {
    display: flex;
    align-items: center;
    gap: 12px;
}
.cs-featured-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid rgba(255,255,255,0.2);
}
.cs-featured-author {
    font-size: 14px;
    font-weight: 500;
    color: #ffffff;
}
.cs-featured-role {
    font-size: 12px;
    color: rgba(255,255,255,0.5);
}
.cs-featured-btn {
    margin-left: auto;
    display: inline-flex;
    align-items: center;
    gap: 6px;
   background: rgba(255,255,255,0.2);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid rgba(255,255,255,0.6);
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.8);
    font-size: 14px;
    font-weight: 500;
    color: #ffffff;
    padding: 8px 16px;
    border-radius: 99px;
    cursor: pointer;
    transition: background 0.2s;
}

.cs-featured-btn svg {
    width: 14px;
    height: 14px;
}

/* ============================================
   TAG PILL
   ============================================ */
.cs-tag {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 3px 10px;
    border-radius: 99px;
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}
.cs-tag--accent {
    background: rgba(16,185,129,0.2);
    color: #6ee7b7;
    border: 1px solid rgba(16,185,129,0.2);
}
.cs-tag--glass {
    background: rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.6);
    border: 1px solid rgba(255,255,255,0.1);
}
/* 行业标签颜色变体 */
.cs-tag--finance { background: #eff6ff; color: #2563eb; border: 1px solid #dbeafe;margin-right: 4px; }
.cs-tag--health { background: #ecfdf5; color: #059669; border: 1px solid #d1fae5; }
.cs-tag--retail { background: #fff7ed; color: #ea580c; border: 1px solid #ffedd5; }
.cs-tag--saas { background: #f5f3ff; color: #7c3aed; border: 1px solid #ede9fe; }
.cs-tag--logistics { background: #fffbeb; color: #d97706; border: 1px solid #fef3c7; }
.cs-tag--default { background: #f4f4f5; color: #52525b; border: 1px solid #e4e4e7; }

/* ============================================
   CASE CARD GRID
   ============================================ */
.cs-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}
@media (min-width: 768px) {
    .cs-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1024px) {
    .cs-grid { grid-template-columns: repeat(3, 1fr); }
}

/* --- Case Card --- */
.cs-card {
    position: relative;
    background: var(--cs-card-bg);
    border: 1px solid rgba(0,0,0,0.07);
    border-radius: var(--cs-radius-lg);
    overflow: hidden;
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1),
                box-shadow 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    cursor: pointer;
}
.cs-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 32px 64px -20px rgba(0,0,0,0.12), 0 0 0 1px rgba(0,0,0,0.05);
}
/* Spotlight effect */
.cs-card::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    opacity: 0;
    transition: opacity 0.3s ease;
    background: radial-gradient(600px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(16,185,129,0.06), transparent 60%);
    pointer-events: none;
}
.cs-card:hover::after { opacity: 1; }

/* Card image */
.cs-card-img-wrap {
    position: relative;
    overflow: hidden;
    height: 274px;
}
.cs-card-img-wrap .card-img {
    width: 100%;
    /* height: 100%; */
    object-fit: cover;
    transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
.cs-card:hover .card-img {
    transform: translateY(0);
}
.cs-card-img-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.3), transparent);
}
.cs-card-img-tag {
    position: absolute;
    bottom: 6px;
    left: 6px;
}

/* Card body */
.cs-card-body {
    padding: 20px;
}
.cs-card-company {
    font-size: 10px;
    font-weight: 600;
    color: var(--cs-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 8px;
}
.cs-card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--cs-text-primary);
    line-height: 1.375;
    letter-spacing: -0.025em;
    margin-bottom: 10px;
}
.cs-card-desc {
    font-size: 12px;
    color: var(--cs-text-tertiary);
    line-height: 1.625;
    margin-bottom: 16px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.cs-card-footer {
    display: flex;
    align-items: center;
    gap: 16px;
    padding-top: 16px;
    border-top: 1px solid #fafafa;
}
.cs-card-metric-val {
    font-family: var(--cs-font-mono);
    font-size: 16px;
    font-weight: 600;
    color: var(--cs-text-primary);
}
.cs-card-metric-label {
    font-size: 10px;
    color: var(--cs-text-tertiary);
    margin-top: 2px;
}
.cs-card-divider {
    width: 1px;
    height: 24px;
    background: #f4f4f5;
}
.cs-card-arrow {
    margin-left: auto;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: #fafafa;
    border: 1px solid #f4f4f5;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    color: var(--cs-text-tertiary);
}
.cs-card-arrow:hover {
    background: var(--cs-text-primary);
    border-color: var(--cs-text-primary);
    color: #ffffff;
}
.cs-card-arrow svg {
    width: 14px;
    height: 14px;
}

/* ============================================
   EMPTY STATE
   ============================================ */
.cs-empty {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 96px 0;
    text-align: center;
}
.cs-empty.show {
    display: flex;
}
.cs-empty-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--cs-radius);
    background: #f4f4f5;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    color: var(--cs-text-tertiary);
}
.cs-empty-icon svg {
    width: 24px;
    height: 24px;
}
.cs-empty-title {
    font-size: 16px;
    font-weight: 600;
    color: #27272a;
    margin-bottom: 4px;
}
.cs-empty-desc {
    font-size: 14px;
    color: var(--cs-text-tertiary);
}

/* ============================================
   LOAD MORE
   ============================================ */
.cs-loadmore {
    display: flex;
    justify-content: center;
    padding-top: 40px;
}
.cs-loadmore-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--cs-card-bg);
    border: 1px solid var(--cs-border);
    border-radius: 99px;
    padding: 12px 32px;
    font-size: 14px;
    font-weight: 500;
    color: var(--cs-text-secondary);
    cursor: pointer;
    transition: all 0.2s;
}
.cs-loadmore-btn:hover {
    background: var(--cs-text-primary);
    color: #ffffff;
    border-color: var(--cs-text-primary);
}

/* ============================================
   FOOTER CTA
   ============================================ */
.cs-cta {
    background: #09090b;
    padding: 64px 24px;
    margin-top: 64px;
}
.cs-cta-inner {
    max-width: 768px;
    margin: 0 auto;
    text-align: center;
}
.cs-cta-title {
    font-size: 30px;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: -0.05em;
    margin-bottom: 16px;
}
@media (min-width: 768px) {
    .cs-cta-title { font-size: 36px; }
}
.cs-cta-desc {
    font-size: 14px;
    color: var(--cs-text-tertiary);
    line-height: 1.625;
    margin-bottom: 32px;
}
.cs-cta-btns {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
}
@media (min-width: 640px) {
    .cs-cta-btns { flex-direction: row; }
}
.cs-cta-primary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--cs-accent);
    color: #ffffff;
    font-size: 14px;
    font-weight: 500;
    padding: 12px 24px;
    border-radius: 99px;
    border: none;
    cursor: pointer;
    transition: background 0.2s;
}
.cs-cta-primary:hover {
    background: #34d399;
}
.cs-cta-primary svg {
    width: 16px;
    height: 16px;
}
.cs-cta-secondary {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--cs-text-muted);
    font-size: 14px;
    padding: 12px 24px;
    border: none;
    background: none;
    cursor: pointer;
    transition: color 0.2s;
}
.cs-cta-secondary:hover {
    color: #ffffff;
}
.cs-cta-secondary svg {
    width: 16px;
    height: 16px;
}

/* ============================================
   RESPONSIVE - Mobile
   ============================================ */
@media (max-width: 768px) {
    .cs-hero { padding-top: 40px; padding-bottom: 24px; }
    .cs-hero-title { font-size: 36px; }
    .cs-hero-right { gap: 12px; }
    .cs-metric-card { padding: 14px; }
    .cs-metric-value { font-size: 20px; }
    .cs-featured { margin-bottom: 20px; }
    .cs-featured-card { border-radius: var(--cs-radius); }
    .cs-featured-img-wrap { height: 220px; }
    .cs-featured-content { padding: 20px; }
    .cs-featured-inner { max-width: 100%; }
    .cs-featured-tags { gap: 6px; margin-bottom: 10px; flex-wrap: wrap; }
    .cs-featured-title { font-size: 20px; margin-bottom: 8px; }
    .cs-featured-desc { font-size: 12px; margin-bottom: 16px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
    .cs-featured-footer { margin-top: 0; }
    .cs-featured-btn { font-size: 12px; padding: 6px 12px; }
    .cs-featured-btn svg { width: 12px; height: 12px; }
    .cs-featured-gradient { background: linear-gradient(to top, rgba(9,9,11,0.85) 0%, rgba(9,9,11,0.5) 50%, transparent 100%); }
    .cs-featured-metrics { gap: 16px; flex-wrap: wrap; }
    .cs-featured-metric-val { font-size: 18px; }
    .cs-card-img-wrap { height: 160px; }
    .cs-card-body { padding: 14px; }
    .cs-card-title { font-size: 14px; margin-bottom: 6px; }
    .cs-card-desc { font-size: 11px; margin-bottom: 10px; }
    .cs-card-footer { padding-top: 10px; }
    .cs-card-arrow { width: 28px; height: 28px; }
    .cs-card-arrow svg { width: 12px; height: 12px; }
    .cs-filter { gap: 12px; margin-bottom: 24px; }
    .cs-grid { gap: 14px; }
    .cs-loadmore { padding-top: 24px; }
    .cs-loadmore-btn { padding: 10px 24px; font-size: 13px; }
    .cs-marquee { margin-bottom: 24px; }
    .cs-marquee-slide { gap: 32px; padding: 0 16px; font-size: 10px; }
}