:root {
    --reactor-blue: #007BFF;
    --graphite-dark: #2F2F2F;
    --safety-yellow: #FFD700;
    --isotope-silver: #E5E4E2;
    --cherenkov-glow: rgba(0, 123, 255, 0.6);
    --concrete-gray: #4A4A4A;
}

body {
    background-color: var(--graphite-dark);
    color: var(--isotope-silver);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Orbitron', sans-serif;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--isotope-silver);
}

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

/* 契倫科夫輝光效果 */
.cherenkov-glow-text {
    text-shadow: 0 0 10px var(--cherenkov-glow), 0 0 20px var(--cherenkov-glow);
}

.cherenkov-glow-box {
    box-shadow: 0 0 15px var(--cherenkov-glow);
    border: 1px solid var(--reactor-blue);
}

/* 導覽列樣式 */
.navbar {
    background-color: rgba(47, 47, 47, 0.95);
    border-bottom: 2px solid var(--reactor-blue);
    backdrop-filter: blur(10px);
}

.navbar-brand {
    font-weight: bold;
    color: var(--reactor-blue) !important;
    text-shadow: 0 0 5px var(--cherenkov-glow);
}

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

.nav-link:hover, .nav-link.active {
    color: var(--reactor-blue) !important;
    text-shadow: 0 0 5px var(--cherenkov-glow);
}

/* 按鈕樣式 */
.btn-atomic {
    background-color: transparent;
    border: 1px solid var(--reactor-blue);
    color: var(--reactor-blue);
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
}

.btn-atomic:hover {
    background-color: var(--reactor-blue);
    color: white;
    box-shadow: 0 0 15px var(--cherenkov-glow);
}

/* 六角形網格背景 (模擬燃料組件) */
.hex-grid {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='28' height='49' viewBox='0 0 28 49'%3E%3Cpath fill='%233a3a3a' fill-opacity='0.4' d='M13.99 9.25l13 7.5v15l-13 7.5L1 31.75v-15l12.99-7.5zM3 17.32v12.86l11 6.35 11-6.35V17.32L14 10.97 3 17.32z'%3E%3C/path%3E%3C/svg%3E");
}

/* 頁尾樣式 */
footer {
    background-color: #1a1a1a;
    border-top: 1px solid var(--concrete-gray);
    padding: 40px 0;
    font-size: 0.85rem;
}

.footer-brand {
    color: var(--reactor-blue);
    font-weight: bold;
}

/* 卡片樣式 */
.atomic-card {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--concrete-gray);
    border-radius: 0;
    transition: all 0.3s ease;
}

.atomic-card:hover {
    border-color: var(--reactor-blue);
    background-color: rgba(0, 123, 255, 0.05);
}

.section-title {
    border-left: 4px solid var(--reactor-blue);
    padding-left: 15px;
    margin-bottom: 30px;
}