/* --- 1. 核心設定 --- */
:root {
    --brand-blue: #1736F5;
    --brand-dark: #0b1a7a;
    --accent-yellow: #FFC709;
    --text-dark: #333333;
}

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

body {
    background-color: var(--brand-blue);
    background-image: radial-gradient(circle at 50% 10%, #4c6aff 0%, var(--brand-blue) 40%, var(--brand-dark) 100%);
    font-family: 'PingFang TC', 'Microsoft JhengHei', sans-serif;
    min-height: 100vh;
    padding: 40px 20px 120px 20px;
    display: flex;
    justify-content: center;
    color: #fff;
}

.container {
    width: 100%;
    max-width: 1100px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

/* --- 2. 標題區 (透明度 0.8) --- */
.header-card {
    grid-column: span 3;
    background: rgba(255, 255, 255, 1);
    backdrop-filter: blur(15px);
    border: 1px solid rgba(255, 255, 255, 0.6);
    border-radius: 30px;
    padding: 40px;
    text-align: left;
    position: relative;
    overflow: hidden;
    box-shadow: 0 15px 35px rgba(0,0,0,0.15);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* [修改] 大標題加粗 */
.header-content h1 { 
    /* 指定特粗黑體 */
    font-family: 'Noto Sans TC', sans-serif;
    font-weight: 900;
    
    font-size: 3rem; 
    margin-bottom: 10px; 
    color: var(--brand-blue); 
    line-height: 1.1;
}

.header-content p { 
    font-size: 1.2rem; 
    color: #333; 
    font-weight: 600;
}

.header-tag {
    background: var(--accent-yellow);
    color: var(--brand-blue);
    font-weight: 900;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 0.85rem;
    display: inline-block;
    margin-bottom: 15px;
}

/* --- 3. 核心邏輯 (黃色強調) --- */
.core-concept-card {
    grid-column: span 3;
    background: var(--accent-yellow);
    color: var(--brand-blue);
    border-radius: 30px;
    padding: 30px;
    text-align: center;
    font-size: 1.5rem;
    font-weight: 900; /* 這裡原本已經 900，但加上 font-family 會更粗 */
    font-family: 'Noto Sans TC', sans-serif; /* [修改] 加粗 */
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 10px;
}
.core-concept-card small { font-size: 1rem; font-weight: normal; color: #333; font-family: 'PingFang TC', sans-serif; }

/* --- 4. 優勢卡片 (透明度 0.5) --- */
.feature-card {
    grid-column: span 1;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(15px);
    border-radius: 30px;
    padding: 30px;
    border: 1px solid rgba(255, 255, 255, 0.4);
    transition: transform 0.3s;
    position: relative;
    overflow: hidden;
}

.feature-card:hover { transform: translateY(-5px); background: rgba(255,255,255,1); }

.feature-icon {
    font-size: 2.5rem; color: var(--brand-blue); margin-bottom: 15px;
}

/* [修改] 優勢卡片標題加粗 */
.feature-card h3 { 
    /* 指定特粗黑體 */
    font-family: 'Noto Sans TC', sans-serif;
    font-weight: 900;
    
    color: var(--brand-blue); 
    font-size: 1.4rem; 
    margin-bottom: 10px; 
}

.feature-card p { color: #333; line-height: 1.5; font-weight: 600; }

/* --- 5. 導流模型圖 (大卡片) --- */
.model-card {
    grid-column: span 2;
    background: var(--accent-yellow);
    backdrop-filter: blur(15px);
    border-radius: 30px;
    padding: 30px;
    border: 1px solid rgba(255, 255, 255, 0.5);
    position: relative;
}

.model-steps {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 20px;
    text-align: center;
}

.step-box {
    background: #fff;
    padding: 20px;
    border-radius: 20px;
    width: 30%;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    position: relative;
}

.step-arrow { color: var(--brand-blue); font-size: 1.5rem; }

/* [修改] 步驟標題加粗 */
.step-box h4 { 
    /* 指定特粗黑體 */
    font-family: 'Noto Sans TC', sans-serif;
    font-weight: 900;
    
    color: var(--brand-blue); 
    margin-bottom: 5px; 
}

.step-box p { color: #666; font-size: 0.9rem; line-height: 1.4; }

/* [修改] 模型大標題加粗 */
.model-card h3 { 
    /* 指定特粗黑體 */
    font-family: 'Noto Sans TC', sans-serif;
    font-weight: 900;
    
    color: #333; 
    font-size: 1.5rem; 
}

/* --- 6. 廣告工具 (TikTok) --- */
.tool-card {
    grid-column: span 1;
    background: #000;
    color: #fff;
    border-radius: 30px;
    padding: 30px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.tool-card::after {
    content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
    background: conic-gradient(from 0deg, transparent, rgba(0, 242, 234, 0.3), rgba(255, 0, 80, 0.3), transparent);
    animation: spin 4s linear infinite;
}
@keyframes spin { 100% { transform: rotate(360deg); } }

.tool-content { position: relative; z-index: 2; background: #000; padding: 20px; border-radius: 20px; width: 100%; height: 100%; display: flex; flex-direction: column; justify-content: center; align-items: center; }

.tool-icon { font-size: 3rem; margin-bottom: 10px; background: -webkit-linear-gradient(45deg, #00f2ea, #ff0050); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }

/* [修改] 工具標題加粗 */
.tool-card h3 {
    /* 指定特粗黑體 */
    font-family: 'Noto Sans TC', sans-serif;
    font-weight: 900;
    font-size: 1.5rem;
    margin-bottom: 5px;
}

.cta-btn {
    background: var(--brand-blue);
    color: #fff;
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    margin-top: 20px;
    display: inline-block;
    transition: 0.3s;
}
.cta-btn:hover { background: var(--accent-yellow); color: var(--brand-blue); }

/* --- 導覽列 --- */
.dock-nav {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(255,255,255,0.25);
    backdrop-filter: blur(20px);
    padding: 15px 30px;
    border-radius: 50px;
    display: flex;
    gap: 20px;
    border: 1px solid rgba(255,255,255,0.4);
    z-index: 100;
}
.dock-nav a { text-decoration: none; color: #fff; font-weight: bold; transition: 0.2s; }
.dock-nav a:hover { color: var(--accent-yellow); transform: translateY(-3px); }

/* RWD */
@media (max-width: 900px) {
    .container { grid-template-columns: 1fr; }
    .header-card, .core-concept-card, .feature-card, .model-card, .tool-card { grid-column: span 1; }
    .model-steps { flex-direction: column; gap: 20px; }
    .step-box { width: 100%; }
    .step-arrow { transform: rotate(90deg); margin: 10px 0; }
    .dock-nav { 
        width: 90%; 
        justify-content: space-between; 
        padding: 12px 20px; 
        gap: 10px;
        bottom: 20px;
    }
    .dock-nav a { font-size: 0.85rem; }
}