:root {
    --primary-bg: #455A64; /* 工坊深石灰 */
    --accent-wood: #795548; /* 胡桃木溫潤棕 */
    --silver-joint: #CFD8DC; /* 精密接合銀 */
    --pressure-blue: #42A5F5; /* 壓力分佈藍 */
    --text-light: #F5F5F5;
    --text-muted: #B0BEC5;
}

body {
    background-color: var(--primary-bg);
    color: var(--text-light);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
}

.mono-font {
    font-family: 'JetBrains Mono', 'Courier New', monospace;
}

.navbar {
    background-color: rgba(69, 90, 100, 0.95);
    border-bottom: 1px solid var(--silver-joint);
    backdrop-filter: blur(10px);
}

.navbar-brand {
    font-weight: 800;
    letter-spacing: 1px;
    color: var(--text-light) !important;
}

.nav-link {
    color: var(--text-muted) !important;
    transition: color 0.3s ease;
}

.nav-link:hover, .nav-link.active {
    color: var(--accent-wood) !important;
}

.btn-outline-accent {
    border-color: var(--accent-wood);
    color: var(--accent-wood);
}

.btn-outline-accent:hover {
    background-color: var(--accent-wood);
    color: white;
}

.section-title {
    border-left: 4px solid var(--accent-wood);
    padding-left: 1rem;
    margin-bottom: 2rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.card-custom {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(207, 216, 220, 0.2);
    border-radius: 0;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.card-custom:hover {
    transform: translateY(-5px);
    border-color: var(--accent-wood);
}

footer {
    border-top: 1px solid var(--silver-joint);
    padding: 3rem 0;
    margin-top: 5rem;
    background: #37474F;
}

/* 構造主義裝飾 */
.structure-line {
    height: 1px;
    background: linear-gradient(90deg, var(--accent-wood), transparent);
    margin: 2rem 0;
}