/* =========================================================
   feature_body.css - 合併整理版
   Purpose: 專屬於 .feature_body 區塊的輪播特色功能樣式
   Note: 所有樣式都限定在 .feature_body 命名空間內，避免全域衝突
   ========================================================= */

/* ===========================================
   1. 主容器 .feature_body
   =========================================== */
.feature_body {
    /* 基本佈局 */
    position: relative;
    display: block;
    padding: 48px 20px;
    margin: 0;
    

    
    /* 字型 */
    font-family: "Inter", "Noto Sans TC", system-ui, -apple-system, "Segoe UI", Roboto, "Microsoft JhengHei", Arial, sans-serif;
    color: #1d1d1f;
}

/* ===========================================
   2. 背景裝飾效果 (偽元素)
   =========================================== */

/* 背景網格 */
.feature_body::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    
    background-image:
        linear-gradient(rgba(15,23,42,.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(15,23,42,.05) 1px, transparent 1px);
    background-size: 56px 56px;
    
    -webkit-mask-image: radial-gradient(circle at 50% 20%, rgba(0,0,0,.9), transparent 70%);
    mask-image: radial-gradient(circle at 50% 20%, rgba(0,0,0,.9), transparent 70%);
    opacity: .85;
}

/* 柔和邊框 */
.feature_body::after {
    content: "";
    position: absolute;
    inset: 18px;
    pointer-events: none;
    z-index: 0;
    
    border-radius: 26px;
    border: 1px solid rgba(15,23,42,.10);
    box-shadow: inset 0 0 0 1px rgba(255,255,255,.55);
    
    -webkit-mask-image: radial-gradient(circle at 50% 35%, rgba(0,0,0,.85), transparent 75%);
    mask-image: radial-gradient(circle at 50% 35%, rgba(0,0,0,.85), transparent 75%);
}

/* ===========================================
   3. 輪播主容器
   =========================================== */
.feature_body .carousel-container {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 1180px;
    margin: 0 auto;
}

/* 大範圍環境光暈 */
.feature_body .carousel-container::before {
    content: "";
    position: absolute;
    inset: -120px;
    pointer-events: none;
    z-index: 0;
    
    background:
        radial-gradient(circle at 50% 30%, rgba(79,70,229,.18), transparent 62%),
        radial-gradient(circle at 10% 10%, rgba(34,197,94,.12), transparent 55%),
        linear-gradient(90deg, rgba(79,70,229,.08), transparent 40%, rgba(34,197,94,.08));
    
    -webkit-mask-image: radial-gradient(circle at center, rgba(0,0,0,.9), transparent 72%);
    mask-image: radial-gradient(circle at center, rgba(0,0,0,.9), transparent 72%);
}

/* 角落科技線條 */
.feature_body .carousel-container::after {
    content: "";
    position: absolute;
    inset: -24px;
    pointer-events: none;
    z-index: 0;
    
    border-radius: 30px;
    box-shadow: inset 0 0 0 1px rgba(15,23,42,.10);
    
    background:
        linear-gradient(90deg, rgba(79,70,229,.12), transparent 28%),
        linear-gradient(180deg, rgba(34,197,94,.10), transparent 34%);
    
    -webkit-mask-image: radial-gradient(circle at center, rgba(0,0,0,.9), transparent 72%);
    mask-image: radial-gradient(circle at center, rgba(0,0,0,.9), transparent 72%);
}

/* ===========================================
   4. 輪播區域
   =========================================== */
.feature_body .carousel {
    position: relative;
    z-index: 1;
    height: 750px;
    overflow: hidden;
    border-radius: 22px;
    
    background:
        linear-gradient(180deg, rgba(79,70,229,.08), transparent 42%),
        rgba(255,255,255,.82);
    border: 1px solid rgba(15,23,42,.08);
    box-shadow: 0 18px 60px rgba(0,0,0,.10), 0 2px 6px rgba(0,0,0,.05);
    backdrop-filter: blur(10px);
}

/* ===========================================
   5. 左右箭頭
   =========================================== */
.feature_body .nav-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,.85);
    border: 1px solid rgba(15,23,42,.08);
    border-radius: 50%;
    cursor: pointer;
    font-size: 24px;
    color: #86868b;
    transition: all 0.3s ease;
    z-index: 10;
}

.feature_body .nav-arrow:hover {
    background: rgba(0, 0, 0, 0.08);
    color: #1d1d1f;
}

.feature_body .nav-arrow:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.feature_body .nav-arrow.prev {
    left: 20px;
}

.feature_body .nav-arrow.next {
    right: 20px;
}

/* ===========================================
   6. 單一卡片 (Slide) 基礎
   =========================================== */
.feature_body .slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.6s ease, visibility 0.6s ease;

    /* 背景效果 (來自 saas-ai.css) */
	background:
    radial-gradient(circle at 30% 30%, rgba(79,70,229,.14), transparent 50%),
    radial-gradient(circle at 70% 20%, rgba(34,197,94,.10), transparent 45%),
    radial-gradient(circle at 20% 70%, rgba(34,197,94,.08), transparent 45%),
    radial-gradient(circle at 80% 80%, rgba(79,70,229,.10), transparent 50%),
    #ffffff;
	}

.feature_body .slide.active {
    opacity: 1;
    visibility: visible;
}

/* 標題下方的裝飾線 - 僅在特定 slide 顯示，避免干擾佈局 */
/* 已移至各 slide 的 .text-section::after 處理 */

/* ===========================================
   7. 通用標題樣式 (Typography)
   =========================================== */
.feature_body .slide .title {
    position: relative;
    display: inline-block;
}

/* 標題下方光暈線 - 預設隱藏，由各 slide 自行啟用 */
.feature_body .slide .title::after {
    content: "";
    position: absolute;
    left: 10%;
    right: 10%;
    bottom: -14px;
    height: 2px;
    border-radius: 999px;
    background: linear-gradient(90deg,
        transparent,
        rgba(79,70,229,.65),
        rgba(34,197,94,.45),
        transparent
    );
    opacity: 0;  /* 預設隱藏 */
}

/* 啟用光暈線的 slide（可選擇性開啟）*/
.feature_body .slide-6 .title::after {
    opacity: .55;
}

.feature_body .slide .subtitle {
    font-size: clamp(16px, 1.6vw, 20px);
    line-height: 1.7;
    color: rgba(55,65,81,.88);
    max-width: 760px;
    margin-left: auto;
    margin-right: auto;
}

.feature_body .kicker {
    display: inline-flex;
    gap: 8px;
    align-items: center;
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(79,70,229,.10);
    border: 1px solid rgba(79,70,229,.18);
    color: rgba(79,70,229,.95);
    font-weight: 700;
    font-size: 12px;
    letter-spacing: .02em;
}

/* ===========================================
   8. 卡片 1：雙AI語言學習互動
   =========================================== */
.feature_body .slide-1 {
    display: flex;
    flex-direction: column;
}

.feature_body .slide-1 .text-section {
    text-align: center;
    margin-bottom: 60px;
    padding-top: 40px;
    position: relative;
}

/* 標題區塊下方裝飾線 */
.feature_body .slide-1 .text-section::after {
    content: "";
    position: absolute;
    left: 9%;
    right: 9%;
    bottom: 0;
    height: 1px;
    background: rgba(15,23,42,.06);
}

.feature_body .slide-1 .title {
    font-size: 48px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-1.active .title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-1 .subtitleX {
    font-size: 22px;
    color: #6E6E73;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease 0.15s, transform 0.6s ease 0.15s;
}

.feature_body .slide-1.active .subtitleX {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-1 .visual-section {
    flex: 0;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    gap: 50px;
}

.feature_body .slide-1 .ai-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    gap: 20px;
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-1.active .ai-card:nth-child(1) {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.3s;
}

.feature_body .slide-1.active .ai-card:nth-child(2) {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.5s;
}

.feature_body .slide-1 .ai-card.main img {
    width: auto;
    height: 420px;
    max-width: 100%;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    object-fit: contain;
}

.feature_body .slide-1 .ai-card.sub img {
    width: auto;
    height: 420px;
    max-width: 100%;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    object-fit: contain;
}

.feature_body .slide-1 .ai-card-label {
    font-size: 20px;
    color: #1d1d1f;
    font-weight: 500;
}

/* ===========================================
   9. 卡片 2：看完影片，馬上有話聊
   =========================================== */
.feature_body .slide-2 {
    display: flex;
    flex-direction: column;
}

.feature_body .slide-2 .text-section {
    text-align: center;
    margin-bottom: 35px;
    padding-top: 40px;
    position: relative;
}

.feature_body .slide-2 .text-section::after {
    content: "";
    position: absolute;
    left: 9%;
    right: 9%;
    bottom: 0;
    height: 1px;
    background: rgba(15,23,42,.06);
}

.feature_body .slide-2 .title {
    font-size: 52px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-2.active .title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-2 .subtitleX {
    font-size: 22px;
    color: #6E6E73;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease 0.15s, transform 0.6s ease 0.15s;
}

.feature_body .slide-2.active .subtitleX {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-2 .visual-section {
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 0;
}

.feature_body .slide-2 .image-card {
    width: 80%;
    max-width: 100%;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
    opacity: 0;
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.feature_body .slide-2 .image-card:first-child {
    transform: translateX(-40px);
    transition-delay: 0.3s;
}

.feature_body .slide-2 .image-card:last-child {
    transform: translateX(40px);
    transition-delay: 0.5s;
}

.feature_body .slide-2.active .image-card {
    opacity: 1;
    transform: translateX(0);
}

.feature_body .slide-2 .image-card img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: contain;
}

.feature_body .slide-2 .connection {
    opacity: 0;
    transition: opacity 0.5s ease 0.7s;
}

.feature_body .slide-2.active .connection {
    opacity: 1;
}

/* 中間連動效果 */
.feature_body .connection {
    position: relative;
    width: 140px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin: 0 10px;
}

.feature_body .connection-line {
    position: absolute;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, #e0e0e0, #3b82f6, #e0e0e0);
    background-size: 200% 100%;
    animation: feature_flowLine 2s linear infinite;
}

.feature_body .dot {
    position: absolute;
    width: 12px;
    height: 12px;
    background: #3b82f6;
    border-radius: 50%;
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.6);
    animation: feature_moveDot 2s ease-in-out infinite;
}

.feature_body .dot:nth-child(2) { animation-delay: 0.5s; opacity: 0.7; }
.feature_body .dot:nth-child(3) { animation-delay: 1s; opacity: 0.5; }

.feature_body .arrow {
    position: absolute;
    width: 0;
    height: 0;
    border-top: 10px solid transparent;
    border-bottom: 10px solid transparent;
    border-left: 14px solid #3b82f6;
    right: 0;
    filter: drop-shadow(0 0 8px rgba(59, 130, 246, 0.5));
    animation: feature_pulseArrow 1.5s ease-in-out infinite;
}

/* ===========================================
   10. 卡片 3：聽說讀寫練習
   =========================================== */
.feature_body .slide-3 {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 100px 60px;
    gap: 10px;
}

.feature_body .slide-3 .content-left {
    flex: 0 0 420px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    padding-bottom: 20px;
}

.feature_body .slide-3 .content-left::after {
    content: "";
    position: absolute;
    left: 0;
    right: -40px;
    bottom: 0;
    height: 1px;
    background: rgba(15,23,42,.06);
}

.feature_body .slide-3 .title {
    font-size: 48px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-3.active .title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-3 .subtitleX {
    font-size: 22px;
    color: #6E6E73;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease 0.15s, transform 0.6s ease 0.15s;
}

.feature_body .slide-3.active .subtitleX {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-3 .content-right {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature_body .slide-3 .practice-image {
    max-width: 100%;
    width: 600px;
    opacity: 0;
    transform: translateX(40px);
    transition: opacity 0.7s ease 0.3s, transform 0.7s ease 0.3s;
}

.feature_body .slide-3.active .practice-image {
    opacity: 1;
    transform: translateX(0);
}

.feature_body .slide-3 .practice-image img {
    width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    object-fit: contain;
}

/* ===========================================
   11. 卡片 4：七個分類 + 100+
   =========================================== */
.feature_body .slide-4 {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.feature_body .slide-4::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0) 70%);
    border-radius: 50%;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
}

.feature_body .slide-4 .visual-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    position: relative;
    z-index: 1;
}

.feature_body .slide-4 .tags-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
    margin-bottom: 50px;
    max-width: 900px;
}

.feature_body .slide-4 .tag {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 28px;
    border-radius: 50px;
    font-family: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, 'Microsoft JhengHei', sans-serif;
    font-size: 18px;
    font-weight: 500;
    color: #1d1d1f;
    opacity: 0;
    transform: translateY(20px) scale(0.95);
    transition: all 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.feature_body .slide-4 .tag .tag-icon {
    font-size: 22px;
}

.feature_body .slide-4 .tag:nth-child(1) { background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%); }
.feature_body .slide-4 .tag:nth-child(2) { background: linear-gradient(135deg, #d1fae5 0%, #a7f3d0 100%); }
.feature_body .slide-4 .tag:nth-child(3) { background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%); }
.feature_body .slide-4 .tag:nth-child(4) { background: linear-gradient(135deg, #fce7f3 0%, #fbcfe8 100%); }
.feature_body .slide-4 .tag:nth-child(5) { background: linear-gradient(135deg, #fed7aa 0%, #fdba74 100%); }
.feature_body .slide-4 .tag:nth-child(6) { background: linear-gradient(135deg, #e0e7ff 0%, #c7d2fe 100%); }
.feature_body .slide-4 .tag:nth-child(7) { background: linear-gradient(135deg, #ccfbf1 0%, #99f6e4 100%); }

.feature_body .slide-4.active .tag {
    opacity: 1;
    transform: translateY(0) scale(1);
}

.feature_body .slide-4.active .tag:nth-child(1) { transition-delay: 0.1s; }
.feature_body .slide-4.active .tag:nth-child(2) { transition-delay: 0.18s; }
.feature_body .slide-4.active .tag:nth-child(3) { transition-delay: 0.26s; }
.feature_body .slide-4.active .tag:nth-child(4) { transition-delay: 0.34s; }
.feature_body .slide-4.active .tag:nth-child(5) { transition-delay: 0.42s; }
.feature_body .slide-4.active .tag:nth-child(6) { transition-delay: 0.50s; }
.feature_body .slide-4.active .tag:nth-child(7) { transition-delay: 0.58s; }

.feature_body .slide-4 .arrow-down {
    font-size: 32px;
    color: #86868b;
    margin-bottom: 40px;
    opacity: 0;
}

.feature_body .slide-4.active .arrow-down {
    animation: feature_fadeInBounce 0.6s ease 0.8s forwards;
}

.feature_body .slide-4 .result-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    opacity: 0;
}

.feature_body .slide-4.active .result-section {
    animation: feature_fadeIn 0.6s ease 1s forwards;
}

.feature_body .slide-4 .number-block {
    display: flex;
    align-items: baseline;
    gap: 12px;
}

.feature_body .slide-4 .number {
    font-size: 88px;
    font-weight: 700;
    line-height: 1;
    color: #3b82f6;
}

.feature_body .slide-4 .number-label {
    font-size: 44px;
    color: #3b82f6;
    font-weight: 600;
}

.feature_body .slide-4 .result-text {
    font-size: 28px;
    font-weight: 500;
    color: #86868b;
}

/* ===========================================
   12. 卡片 5：任何裝置
   =========================================== */
.feature_body .slide-5 {
    display: flex;
    align-items: center;
    padding: 40px 80px 60px;
    gap: 60px;
}

.feature_body .slide-5 .content-left {
    flex: 0 0 380px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    padding-bottom: 20px;
}

.feature_body .slide-5 .content-left::after {
    content: "";
    position: absolute;
    left: 0;
    right: -30px;
    bottom: 0;
    height: 1px;
    background: rgba(15,23,42,.06);
}

.feature_body .slide-5 .pre-title {
    font-size: 18px;
    color: #86868b;
    margin-bottom: 10px;
    font-weight: 500;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-5.active .pre-title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-5 .title {
    font-size: 44px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
    line-height: 1.2;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease 0.1s, transform 0.6s ease 0.1s;
}

.feature_body .slide-5.active .title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-5 .subtitleX {
    font-size: 22px;
    color: #6E6E73;
    line-height: 1.5;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease 0.2s, transform 0.6s ease 0.2s;
}

.feature_body .slide-5.active .subtitleX {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-5 .content-right {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature_body .slide-5 .devices-image {
    max-width: 100%;
    width: 100%;
    opacity: 0;
    transform: translateX(40px);
    transition: opacity 0.7s ease 0.3s, transform 0.7s ease 0.3s;
}

.feature_body .slide-5.active .devices-image {
    opacity: 1;
    transform: translateX(0);
}

.feature_body .slide-5 .devices-image img {
    width: 100%;
    height: auto;
    object-fit: contain;
}

/* ===========================================
   13. 卡片 6：CTA
   =========================================== */
.feature_body .slide-6 {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.feature_body .slide-6 .text-section {
    text-align: center;
    margin-bottom: 60px;
    padding-top: 40px;
    position: relative;
}

.feature_body .slide-6 .text-section::after {
    content: "";
    position: absolute;
    left: 15%;
    right: 15%;
    bottom: -20px;
    height: 1px;
    background: rgba(15,23,42,.06);
}

.feature_body .slide-6 .title {
    font-size: 42px;
    font-weight: 600;
    color: #1d1d1f;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.feature_body .slide-6.active .title {
    opacity: 1;
    transform: translateY(0);
}

.feature_body .slide-6 .cta-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature_body .slide-6 .cta-button {
    position: relative;
    z-index: 2;
    background: linear-gradient(135deg, #0071e3 0%, #00a1e3 100%);
    color: #ffffff;
    font-size: 26px;
    font-weight: 600;
    padding: 28px 80px;
    border-radius: 980px;
    border: none;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 10px 40px rgba(0, 113, 227, 0.35);
}

.feature_body .slide-6 .cta-button:hover {
    transform: scale(1.03);
    box-shadow: 0 15px 50px rgba(0, 113, 227, 0.45);
}

.feature_body .slide-6 .pulse-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    border-radius: 980px;
    border: 3px solid rgba(0, 113, 227, 0.4);
    opacity: 0;
}

.feature_body .slide-6.active .pulse-ring {
    animation: feature_pulseRing 2s ease-out infinite;
}

.feature_body .slide-6.active .pulse-ring:nth-child(2) {
    animation-delay: 0.5s;
}

.feature_body .slide-6.active .pulse-ring:nth-child(3) {
    animation-delay: 1s;
}

/* ===========================================
   14. 導航控制
   =========================================== */
.feature_body .navigation {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 30px;
}

.feature_body .nav-dots {
    display: flex;
    gap: 12px;
}

.feature_body .nav-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #d1d1d6;
    cursor: pointer;
    transition: all 0.3s ease;
}

.feature_body .nav-dot.active {
    background: rgba(79,70,229,.88);
    transform: scale(1.2);
}

.feature_body .nav-dot:hover {
    background: #86868b;
}

/* ===========================================
   15. 動畫 Keyframes (加上 feature_ 前綴避免衝突)
   =========================================== */
@keyframes feature_flowLine {
    0% { background-position: 100% 0; }
    100% { background-position: -100% 0; }
}

@keyframes feature_moveDot {
    0% { left: 0; opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { left: calc(100% - 12px); opacity: 0; }
}

@keyframes feature_pulseArrow {
    0%, 100% { opacity: 1; transform: translateX(0); }
    50% { opacity: 0.6; transform: translateX(3px); }
}

@keyframes feature_fadeInBounce {
    0% { opacity: 0; transform: translateY(-10px); }
    100% { opacity: 1; transform: translateY(0); }
}

@keyframes feature_fadeIn {
    to { opacity: 1; }
}

@keyframes feature_pulseRing {
    0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.8;
    }
    100% {
        transform: translate(-50%, -50%) scale(1.5);
        opacity: 0;
    }
}

/* ===========================================
   16. 響應式設計
   =========================================== */

/* ----- 1200px 以下 ----- */
@media (max-width: 1200px) {
    .feature_body .slide { padding: 40px 50px; }
    .feature_body .slide-1 .title,
    .feature_body .slide-2 .title { font-size: 42px; }
    .feature_body .slide-2 .image-card { width: 380px; }
    .feature_body .slide-1 .ai-card.main img,
    .feature_body .slide-1 .ai-card.sub img { 
        height: 320px; 
    }
    .feature_body .slide-3 { flex-direction: column; gap: 40px; padding: 50px; }
    .feature_body .slide-3 .content-left { flex: none; text-align: center; align-items: center; }
    .feature_body .slide-5 { flex-direction: column; gap: 40px; padding: 50px; }
    .feature_body .slide-5 .content-left { flex: none; text-align: center; }
}

/* ----- 900px 以下 ----- */
@media (max-width: 900px) {
    .feature_body { padding: 20px 10px; }
    
    .feature_body .carousel { 
        height: auto; 
        min-height: 600px; 
        border-radius: 16px;
    }
    
    .feature_body .slide { padding: 30px 20px; }
    
    /* 卡片 1 手機版優化 */
    .feature_body .slide-1 .title { font-size: 32px; margin-bottom: 12px; }
    .feature_body .slide-1 .subtitleX { font-size: 18px; }
    .feature_body .slide-1 .text-section { margin-bottom: 30px; }
    .feature_body .slide-1 .visual-section { 
        flex-direction: column; 
        gap: 25px;
        align-items: center;
    }
    .feature_body .slide-1 .ai-card { width: 100%; }
    .feature_body .slide-1 .ai-card.main img,
    .feature_body .slide-1 .ai-card.sub img { 
        width: 85%;
        height: auto;
        max-height: 280px;
    }
    .feature_body .slide-1 .ai-card-label { font-size: 16px; }
    
    /* 卡片 2 手機版優化 */
    .feature_body .slide-2 .title { font-size: 32px; }
    .feature_body .slide-2 .subtitleX { font-size: 18px; }
    .feature_body .slide-2 .text-section { margin-bottom: 30px; }
    .feature_body .slide-2 .visual-section { 
        flex-direction: column; 
        gap: 20px; 
    }
    .feature_body .slide-2 .image-card { 
        width: 85%;
        max-width: 85%;
    }
    .feature_body .connection { 
        transform: rotate(90deg); 
        width: 80px; 
        height: 50px; 
        margin: 10px 0; 
    }
    
    /* 卡片 3 手機版優化 */
    .feature_body .slide-3 .title { font-size: 32px; }
    .feature_body .slide-3 .subtitleX { font-size: 18px; }
    .feature_body .slide-3 .practice-image { width: 100%; }
    
    /* 卡片 4 手機版優化 */
    .feature_body .slide-4 .tags-container { 
        gap: 12px; 
        margin-bottom: 30px; 
        padding: 0 10px;
    }
    .feature_body .slide-4 .tag { 
        padding: 12px 20px; 
        font-size: 16px; 
    }
    .feature_body .slide-4 .tag .tag-icon { font-size: 18px; }
    .feature_body .slide-4 .arrow-down { 
        font-size: 28px; 
        margin-bottom: 30px; 
    }
    .feature_body .slide-4 .number { font-size: 64px; }
    .feature_body .slide-4 .number-label { font-size: 32px; }
    .feature_body .slide-4 .result-text { font-size: 20px; }
    
    /* 卡片 5 手機版優化 */
    .feature_body .slide-5 .title { font-size: 32px; }
    .feature_body .slide-5 .subtitleX { font-size: 18px; }
    .feature_body .slide-5 .pre-title { font-size: 16px; }
    
    /* 卡片 6 手機版優化 */
    .feature_body .slide-6 .title { font-size: 32px; }
    .feature_body .slide-6 .text-section { margin-bottom: 40px; }
    .feature_body .slide-6 .cta-button { 
        font-size: 20px; 
        padding: 20px 50px; 
    }
    
    /* 箭頭按鈕手機版調整 */
    .feature_body .nav-arrow { 
        width: 40px; 
        height: 40px; 
        font-size: 20px; 
    }
    .feature_body .nav-arrow.prev { left:  0px;}
    .feature_body .nav-arrow.next { right: 0px;}
}

/* ----- 600px 以下 ----- */
@media (max-width: 600px) {
    .feature_body .carousel { min-height: 550px; }
    .feature_body .slide { padding: 25px 15px; }

    .feature_body .slide-3 {
		gap:20px;
	}
    
    /* 進一步縮小字體 */
    .feature_body .slide-1 .title, 
    .feature_body .slide-2 .title,
    .feature_body .slide-3 .title,
    .feature_body .slide-5 .title,
    .feature_body .slide-6 .title { font-size: 28px; }
    
    .feature_body .slide-1 .subtitleX, 
    .feature_body .slide-2 .subtitleX,
    .feature_body .slide-3 .subtitleX,
    .feature_body .slide-5 .subtitleX { font-size: 16px; }
    
    /* 圖片進一步優化 */
    .feature_body .slide-1 .ai-card.main img,
    .feature_body .slide-1 .ai-card.sub img { 
        max-height: 240px;
    }
    
    .feature_body .slide-4 .tag { 
        padding: 10px 16px; 
        font-size: 14px; 
    }
    
    .feature_body .slide-4 .number { font-size: 56px; }
    .feature_body .slide-4 .number-label { font-size: 28px; }
    .feature_body .slide-4 .result-text { font-size: 18px; }
    
    .feature_body .slide-6 .cta-button { 
        font-size: 18px; 
        padding: 18px 40px; 
    }
    
    /* 導航點調整 */
    .feature_body .nav-dots { gap: 8px; }
    .feature_body .nav-dot { 
        width: 8px; 
        height: 8px; 
    }
}

/* ----- 400px 以下 (超小螢幕) ----- */
@media (max-width: 400px) {
    .feature_body .carousel { min-height: 500px; }
    .feature_body .slide { padding: 20px 12px; }
    
    .feature_body .slide-1 .title, 
    .feature_body .slide-2 .title,
    .feature_body .slide-3 .title,
    .feature_body .slide-5 .title,
    .feature_body .slide-6 .title { font-size: 24px; }
    
    .feature_body .slide-1 .ai-card.main img,
    .feature_body .slide-1 .ai-card.sub img { 
        max-height: 200px;
    }
    
    .feature_body .slide-6 .cta-button { 
        font-size: 16px; 
        padding: 16px 32px; 
    }
}