:root {
    --c-steel-dark: #121619;
    --c-steel-mid: #1c2226;
    --c-steel-light: #2c353c;
    --c-brass: #c8963e;
    --c-brass-dark: #8c631e;
    --c-copper: #b85d38;
    --c-amber: #ffaa00;
    --c-amber-dim: #996600;
    --c-olive: #2b3324;
    --c-rust: #8a3422;
}

body {
    background-color: var(--c-steel-dark);
    color: #d1d5db;
    font-family: 'Chakra Petch', sans-serif;
    background-image: radial-gradient(circle at 50% 20%, rgba(200, 150, 62, 0.05) 0%, transparent 60%),
    linear-gradient(rgba(18, 22, 25, 0.94), rgba(18, 22, 25, 0.98)),
    repeating-linear-gradient(0deg, transparent, transparent 2px, rgba(0, 0, 0, 0.3) 2px, rgba(0, 0, 0, 0.3) 4px);
    background-attachment: fixed;
    overflow-x: hidden;
}

.tactical-grid-bg {
    background-image: linear-gradient(to right, rgba(200, 150, 62, 0.07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(200, 150, 62, 0.07) 1px, transparent 1px);
    background-size: 30px 30px;
}

.font-header {
    font-family: 'Teko', sans-serif;
    letter-spacing: 2px;
    text-transform: uppercase;
}

.font-mono-tactical {
    font-family: 'Share Tech Mono', monospace;
}

.steel-plate {
    background: linear-gradient(180deg, #1c1f26 0%, #13151a 100%);
    border: 1px solid #000;
    border-radius: 6px;
    box-shadow: inset 0 2px 1px rgba(255, 255, 255, 0.05), inset 0 -2px 4px rgba(0, 0, 0, 0.8), 0 4px 12px rgba(0, 0, 0, 0.6);
    position: relative;
}

.steel-plate-brass {
    background: linear-gradient(180deg, #1c1f26 0%, #13151a 100%);
    border: 1px solid #000;
    border-left: 4px solid var(--c-brass);
    border-radius: 6px;
    box-shadow: inset 0 2px 1px rgba(255, 255, 255, 0.05), inset 0 -2px 4px rgba(0, 0, 0, 0.8), 0 4px 12px rgba(0, 0, 0, 0.6);
    position: relative;
}

.riveted::before, .riveted::after {
    content: '';
    position: absolute;
    width: 8px;
    height: 8px;
    background: radial-gradient(circle at 30% 30%, #5a6772, #111417);
    border-radius: 50%;
    box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.3), 0 1px 2px rgba(0, 0, 0, 0.9);
    z-index: 10;
}

.riveted::before {
    top: 6px;
    left: 6px;
}

.riveted::after {
    top: 6px;
    right: 6px;
}

.riveted-bottom::before, .riveted-bottom::after {
    content: '';
    position: absolute;
    width: 8px;
    height: 8px;
    background: radial-gradient(circle at 30% 30%, #5a6772, #111417);
    border-radius: 50%;
    box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.3), 0 1px 2px rgba(0, 0, 0, 0.9);
    z-index: 10;
}

.riveted-bottom::before {
    bottom: 6px;
    left: 6px;
}

.riveted-bottom::after {
    bottom: 6px;
    right: 6px;
}

.btn-industrial {
    background: linear-gradient(180deg, #c8963e 0%, #8c631e 100%);
    color: #0d1012;
    font-weight: 700;
    text-transform: uppercase;
    border: 1px solid #000;
    border-radius: 4px;
    position: relative;
    top: 0;
    box-shadow: 0 3px 0 #0a0b0d, inset 0 1px 0 rgba(255, 255, 255, 0.4);
    transition: background 0.1s, top 0.05s, box-shadow 0.05s;
    text-shadow: 0 1px 0 rgba(255, 255, 255, 0.2);
    cursor: pointer;
}

.btn-industrial:hover {
    background: linear-gradient(180deg, #dbab50 0%, #a07224 100%);
}

.btn-industrial:active {
    top: 2px;
    box-shadow: 0 1px 0 #0a0b0d, inset 0 2px 4px rgba(0, 0, 0, 0.8);
}

.btn-copper {
    background: linear-gradient(180deg, #b85d38 0%, #73341b 100%);
    color: #f3f4f6;
    font-weight: 700;
    text-transform: uppercase;
    border: 1px solid #000;
    border-radius: 4px;
    position: relative;
    top: 0;
    box-shadow: 0 3px 0 #0a0b0d, inset 0 1px 0 rgba(255, 255, 255, 0.3);
    transition: background 0.1s, top 0.05s, box-shadow 0.05s;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.8);
    cursor: pointer;
}

.btn-copper:hover {
    background: linear-gradient(180deg, #cd6e47 0%, #8a3f23 100%);
}

.btn-copper:active {
    top: 2px;
    box-shadow: 0 1px 0 #0a0b0d, inset 0 2px 4px rgba(0, 0, 0, 0.8);
}

.radar-scope {
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: radial-gradient(circle, #0e1710 0%, #060b07 100%);
    border: 3px solid #2d3b2a;
    box-shadow: inset 0 0 24px rgba(0, 0, 0, 0.95), 0 2px 8px rgba(0, 0, 0, 0.8);
    position: relative;
    overflow: hidden;
}

.radar-sweep {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 50%;
    height: 50%;
    background: linear-gradient(135deg, rgba(255, 170, 0, 0.4) 0%, transparent 70%);
    transform-origin: 0% 0%;
    animation: radarSweep 4s linear infinite;
    border-right: 1px solid rgba(255, 170, 0, 0.8);
}

@keyframes radarSweep {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

.gauge-meter {
    height: 10px;
    background: #080a0c;
    border: 1px solid #000;
    border-radius: 2px;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.95);
    position: relative;
    overflow: hidden;
}

.gauge-fill-amber {
    height: 100%;
    background: linear-gradient(90deg, #8c631e 0%, #c8963e 50%, #ffaa00 100%);
}

.nav-link-active {
    color: #ffaa00 !important;
    border-bottom: 2px solid #c8963e;
}

/* Thin Industrial Scrollbar (Standard & WebKit) */
* {
    scrollbar-width: thin;
    scrollbar-color: #3a454e #0b0e10;
}

::-webkit-scrollbar {
    width: 5px;
    height: 5px;
}

::-webkit-scrollbar-button {
    display: none;
    width: 0;
    height: 0;
}

::-webkit-scrollbar-track {
    background: #0b0e10;
    border-left: 1px solid #1a2228;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, #3a454e 0%, #20272c 100%);
    border-radius: 2px;
    border: 1px solid #4a5763;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, #c8963e 0%, #8c631e 100%);
    border-color: #ffaa00;
}

/* Tactical Amber Text Selection */
::selection {
    background: #c8963e;
    color: #0b0e10;
    text-shadow: none;
}

::-moz-selection {
    background: #c8963e;
    color: #0b0e10;
    text-shadow: none;
}

/* Interactive & UI Element Selection Locking */
button,
.btn-industrial,
.btn-copper,
header,
nav,
th,
.gauge-meter,
.radar-scope,
.radar-scope-container,
.fcs-chassis,
.fcs-heavy-fire-btn,
.fcs-status-badge,
i.fa-solid,
i.fa-regular,
i.fa-brands,
svg {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}