/* Data Center Server Rack Style - Vertical Rack Layout */
@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500;700&family=Inter:wght@400;600;800&display=swap');

:root {
    --dc-bg: #0a0a0a;
    --dc-rack-bg: #121212;
    --dc-rack-border: #333333;
    --dc-rack-metal: #222222;
    --dc-led-green: #00ff41;
    --dc-led-blue: #00b8ff;
    --dc-led-red: #ff003c;
    --dc-led-orange: #ffb000;
    --dc-text: #a0a0a0;
    --dc-white: #ffffff;
    --font-code: 'Fira Code', monospace;
    --font-sans: 'Inter', sans-serif;
}

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

body {
    background-color: var(--dc-bg);
    color: var(--dc-text);
    font-family: var(--font-sans);
    line-height: 1.6;
    /* Server room floor texture */
    background-image: 
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 50px 50px;
    padding: 20px;
    display: flex;
    justify-content: center;
}

h1, h2, h3, h4 { font-weight: 800; color: var(--dc-white); letter-spacing: -0.5px; }
a { text-decoration: none; color: inherit; transition: 0.2s; }
img { max-width: 100%; height: auto; display: block; border: 1px solid var(--dc-rack-border); filter: grayscale(50%) contrast(1.2); }

/* Layout: The Server Rack */
.server-rack {
    width: 100%;
    max-width: 1200px;
    background: var(--dc-rack-bg);
    border: 10px solid var(--dc-rack-metal);
    border-radius: 4px;
    box-shadow: 
        inset 0 0 20px rgba(0,0,0,1),
        0 20px 50px rgba(0,0,0,0.8),
        -5px 0 10px rgba(255,255,255,0.05) inset;
    display: flex;
    flex-direction: column;
    gap: 15px; /* Space between U-units */
    padding: 15px;
}

/* Rack Mounting Holes (Decorative sidebars) */
.server-rack::before, .server-rack::after {
    content: '';
    position: fixed;
    top: 0; bottom: 0;
    width: 30px;
    background: var(--dc-rack-metal);
    background-image: radial-gradient(circle, #000 4px, transparent 5px);
    background-size: 100% 30px;
    z-index: -1;
}
.server-rack::before { left: calc(50% - 630px); }
.server-rack::after { right: calc(50% - 630px); }

/* Base Server Unit (U) */
.u-unit {
    background: #181818;
    border: 1px solid var(--dc-rack-border);
    border-radius: 2px;
    position: relative;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.05), 0 5px 10px rgba(0,0,0,0.5);
    overflow: hidden;
}
/* Unit Handles */
.u-unit::before, .u-unit::after {
    content: ''; position: absolute; top: 10px; bottom: 10px; width: 15px;
    background: linear-gradient(to right, #222, #333, #111);
    border: 1px solid #000; border-radius: 2px;
}
.u-unit::before { left: 5px; }
.u-unit::after { right: 5px; }

/* Unit Content Area */
.u-content {
    padding: 20px 40px;
    margin: 0 25px; /* Avoid handles */
    border-left: 1px solid #000;
    border-right: 1px solid #000;
    background: linear-gradient(to bottom, #1a1a1a, #151515);
}

/* LED Indicators */
.led-panel {
    display: flex;
    gap: 10px;
    position: absolute;
    top: 15px; right: 40px;
}
.led {
    width: 8px; height: 8px; border-radius: 50%; background: #333;
}
.led.green { background: var(--dc-led-green); box-shadow: 0 0 8px var(--dc-led-green); }
.led.blue { background: var(--dc-led-blue); box-shadow: 0 0 8px var(--dc-led-blue); }
.led.red { background: var(--dc-led-red); box-shadow: 0 0 8px var(--dc-led-red); animation: blink 1s infinite; }
.led.blink-fast { animation: blink 0.2s infinite; }
@keyframes blink { 0%, 49% { opacity: 1; } 50%, 100% { opacity: 0.2; } }

/* Unit Label */
.u-label {
    position: absolute;
    top: 10px; left: 40px;
    font-family: var(--font-code);
    font-size: 0.7rem;
    color: #555;
    text-transform: uppercase;
}

/* Buttons (Server Switches) */
.btn-sys {
    display: inline-block;
    background: #222;
    color: var(--dc-white);
    font-family: var(--font-code);
    font-size: 0.85rem;
    padding: 10px 20px;
    border: 1px solid #444;
    border-bottom: 3px solid #111;
    border-radius: 3px;
    cursor: pointer;
    text-transform: uppercase;
    transition: 0.1s;
}
.btn-sys:active, .btn-sys.active { transform: translateY(2px); border-bottom-width: 1px; background: #2a2a2a; }
.btn-sys.primary { color: var(--dc-led-green); border-color: var(--dc-led-green); }
.btn-sys.primary:hover { background: rgba(0, 255, 65, 0.1); box-shadow: 0 0 15px rgba(0, 255, 65, 0.2); }

/* --- Specific Units --- */

/* 1. Master Control Unit (Nav) */
.master-unit .u-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 40px;
}
.brand { font-size: 1.5rem; color: var(--dc-white); display: flex; align-items: center; gap: 10px; }
.brand span { font-family: var(--font-code); font-size: 0.7rem; color: var(--dc-led-blue); border: 1px solid var(--dc-led-blue); padding: 2px 5px; }
.sys-nav { display: flex; gap: 20px; font-family: var(--font-code); font-size: 0.85rem; }
.sys-nav a:hover { color: var(--dc-led-green); }

/* 2. Core Processing Unit (Hero) */
.core-unit .u-content {
    padding: 60px 40px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    background: radial-gradient(circle at right, rgba(0, 184, 255, 0.05) 0%, transparent 50%), #151515;
}
.core-unit h1 { font-size: 3.5rem; margin-bottom: 20px; line-height: 1.1; }
.core-unit p { font-size: 1.1rem; max-width: 700px; margin-bottom: 30px; color: #ccc; }
.core-actions { display: flex; gap: 20px; margin-bottom: 30px; }
.sys-status { display: flex; gap: 20px; font-family: var(--font-code); font-size: 0.8rem; color: var(--dc-led-green); }

/* 3. Telemetry Unit (Data Metrics) */
.telemetry-unit .u-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    padding: 30px 40px;
}
.metric-display {
    background: #000;
    border: 1px solid #333;
    padding: 20px;
    text-align: center;
    position: relative;
}
.metric-display::before { content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 2px; background: var(--dc-led-blue); }
.metric-val { font-family: var(--font-code); font-size: 2.5rem; color: var(--dc-led-blue); line-height: 1; margin-bottom: 5px; }
.metric-lbl { font-size: 0.8rem; text-transform: uppercase; color: #888; }

/* 4. Storage Array (Features) */
.storage-unit .u-content {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    padding: 40px;
}
.drive-bay {
    background: #111;
    border: 1px solid #222;
    padding: 20px;
}
.drive-bay img { height: 150px; width: 100%; object-fit: cover; margin-bottom: 20px; border-bottom: 2px solid var(--dc-led-green); }
.drive-bay h3 { font-size: 1.2rem; margin-bottom: 10px; }
.drive-bay p { font-size: 0.9rem; color: #999; }

/* 5. Network Switch (Nodes) */
.switch-unit .u-content {
    padding: 40px;
}
.switch-unit h2 { margin-bottom: 20px; font-size: 1.5rem; }
.port-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 10px;
    background: #000;
    padding: 20px;
    border: 1px solid #333;
}
.port {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    background: #111;
    border: 1px solid #222;
    font-family: var(--font-code);
    font-size: 0.85rem;
}
.port-status { width: 6px; height: 6px; background: var(--dc-led-green); border-radius: 50%; margin-right: 10px; }
.port-id { color: var(--dc-white); flex: 1; }
.port-speed { color: var(--dc-led-blue); }

/* 6. Log Server (Reviews) */
.log-unit .u-content {
    padding: 40px;
}
.log-unit h2 { margin-bottom: 20px; font-size: 1.5rem; }
.log-terminal {
    background: #000;
    border: 1px solid #333;
    padding: 20px;
    font-family: var(--font-code);
    font-size: 0.85rem;
    height: 250px;
    overflow-y: auto;
}
.log-terminal::-webkit-scrollbar { width: 5px; }
.log-terminal::-webkit-scrollbar-thumb { background: #333; }
.log-entry { margin-bottom: 15px; border-bottom: 1px dashed #222; padding-bottom: 10px; }
.log-time { color: #666; margin-right: 10px; }
.log-user { color: var(--dc-led-orange); margin-right: 10px; }
.log-msg { color: #ccc; }

/* 7. Power Distribution Unit (Pricing) */
.pdu-unit .u-content {
    padding: 40px;
}
.pdu-unit h2 { margin-bottom: 20px; font-size: 1.5rem; }
.power-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}
.power-module {
    background: #111;
    border: 1px solid #333;
    padding: 30px;
    text-align: center;
    display: flex;
    flex-direction: column;
}
.power-module.active { border-color: var(--dc-led-green); box-shadow: inset 0 0 20px rgba(0, 255, 65, 0.05); }
.pm-name { font-family: var(--font-code); font-size: 1.1rem; margin-bottom: 15px; color: var(--dc-white); }
.pm-price { font-size: 2.5rem; font-weight: 800; color: var(--dc-led-green); margin-bottom: 20px; line-height: 1; }
.pm-price span { font-size: 1rem; color: #666; }
.pm-specs { list-style: none; text-align: left; margin-bottom: 30px; flex: 1; }
.pm-specs li { padding: 8px 0; border-bottom: 1px solid #222; font-size: 0.9rem; }
.pm-specs li::before { content: '>'; font-family: var(--font-code); color: var(--dc-led-blue); margin-right: 10px; }

/* 8. Diagnostics Unit (FAQ & Footer) */
.diag-unit .u-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 40px;
    padding: 40px;
}
.diag-unit h3 { font-size: 1.2rem; margin-bottom: 20px; color: #888; }
.faq-item { margin-bottom: 20px; }
.faq-q { font-weight: 600; color: var(--dc-white); margin-bottom: 5px; }
.faq-a { font-size: 0.9rem; color: #999; }
.sys-links { display: flex; flex-direction: column; gap: 10px; font-family: var(--font-code); font-size: 0.85rem; }
.sys-links a:hover { color: var(--dc-led-blue); }
.sys-copy { margin-top: 30px; font-family: var(--font-code); font-size: 0.75rem; color: #555; }

/* Subpages */
.sub-hero { padding: 60px 40px; text-align: center; }
.sub-hero h1 { font-size: 3rem; margin-bottom: 15px; }
.dl-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; padding: 40px; }
.dl-card { background: #111; border: 1px solid #333; padding: 30px; text-align: center; }
.dl-icon { font-size: 3rem; margin-bottom: 20px; }
.help-grid { display: grid; grid-template-columns: 250px 1fr; gap: 30px; padding: 40px; }
.help-nav { display: flex; flex-direction: column; gap: 10px; }
.help-section { margin-bottom: 40px; }
.help-section h3 { color: var(--dc-white); border-bottom: 1px solid #333; padding-bottom: 10px; margin-bottom: 20px; }
.help-section h4 { margin-top: 20px; margin-bottom: 10px; color: var(--dc-led-blue); }
.help-section ul { padding-left: 20px; margin-bottom: 15px; }

/* Responsive */
@media (max-width: 1024px) {
    .telemetry-unit .u-content { grid-template-columns: repeat(2, 1fr); }
    .storage-unit .u-content { grid-template-columns: repeat(2, 1fr); }
    .power-grid { grid-template-columns: repeat(2, 1fr); }
    .diag-unit .u-content { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
    .server-rack::before, .server-rack::after { display: none; }
    .server-rack { border-width: 2px; padding: 5px; }
    .u-unit::before, .u-unit::after { display: none; }
    .u-content { margin: 0; padding: 20px; }
    .master-unit .u-content { flex-direction: column; gap: 15px; }
    .sys-nav { flex-wrap: wrap; justify-content: center; }
    .core-unit h1 { font-size: 2.5rem; }
    .core-actions { flex-direction: column; }
    .sys-status { flex-direction: column; gap: 5px; }
    .storage-unit .u-content, .power-grid { grid-template-columns: 1fr; }
    .dl-grid, .help-grid { grid-template-columns: 1fr; }
}