:root {
    --titanium-gray: #546E7A;
    --vector-blue: #0288D1;
    --separation-white: #F1F8E9;
    --sediment-brown: #5D4037;
    --dark-bg: #1a1a1a;
    --industrial-font: 'Roboto Mono', monospace;
    --main-font: 'Inter', sans-serif;
}

body {
    background-color: var(--dark-bg);
    color: var(--separation-white);
    font-family: var(--main-font);
    overflow-x: hidden;
}

.navbar {
    background-color: rgba(26, 26, 26, 0.95);
    border-bottom: 1px solid var(--titanium-gray);
    backdrop-filter: blur(10px);
}

.navbar-brand {
    font-weight: 800;
    letter-spacing: 2px;
    color: var(--vector-blue) !important;
}

.nav-link {
    color: var(--separation-white) !important;
    font-size: 0.9rem;
    text-transform: uppercase;
    margin: 0 10px;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--vector-blue) !important;
}

.hero-section {
    min-height: 100vh;
    padding-top: 100px;
    background: radial-gradient(circle at center, #263238 0%, #1a1a1a 100%);
    position: relative;
    overflow: hidden;
}

.vortex-container {
    position: relative;
    width: 100%;
    height: 500px;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* 模擬離心機轉鼓動畫 */
.decanter-drum {
    width: 600px;
    height: 200px;
    background: linear-gradient(to bottom, #546E7A, #37474F);
    border-radius: 100px / 50px;
    position: relative;
    box-shadow: 0 0 50px rgba(2, 136, 209, 0.2);
    animation: rotate-vibration 0.1s infinite linear;
}

@keyframes rotate-vibration {
    0% { transform: translate(0, 0) rotate(0.5deg); }
    50% { transform: translate(1px, 1px) rotate(-0.5deg); }
    100% { transform: translate(0, 0) rotate(0.5deg); }
}

.fluid-layer {
    position: absolute;
    height: 100%;
    width: 100%;
    border-radius: inherit;
    opacity: 0.6;
}

.layer-heavy { background: var(--sediment-brown); transform: scaleY(0.9); }
.layer-medium { background: var(--vector-blue); transform: scaleY(0.6); }
.layer-light { background: var(--separation-white); transform: scaleY(0.3); }

.metric-card {
    background: rgba(84, 110, 122, 0.1);
    border: 1px solid var(--titanium-gray);
    padding: 20px;
    border-radius: 4px;
    transition: all 0.3s;
}

.metric-card:hover {
    border-color: var(--vector-blue);
    background: rgba(2, 136, 209, 0.05);
}

.metric-value {
    font-family: var(--industrial-font);
    font-size: 1.5rem;
    color: var(--vector-blue);
}

.section-title {
    border-left: 4px solid var(--vector-blue);
    padding-left: 15px;
    margin-bottom: 40px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.footer {
    padding: 50px 0;
    border-top: 1px solid var(--titanium-gray);
    background: #111;
}

/* 響應式調整 */
@media (max-width: 768px) {
    .decanter-drum { width: 90%; height: 150px; }
}