/* ===== RESET ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;border:0;font:inherit;vertical-align:baseline}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-padding-top:1rem}
body{min-height:100vh;line-height:1.6;background:var(--color-dark-ink);color:var(--color-warm-paper);font-family:var(--font-body);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
img,svg,video{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
ul,ol{list-style:none}
button{cursor:pointer;font:inherit;color:inherit;background:none}
input,textarea,select{font:inherit;color:inherit}
table{border-collapse:collapse;border-spacing:0}
:focus-visible{outline:2px solid var(--color-vibrant-orange);outline-offset:2px;border-radius:2px}

/* ===== CSS VARIABLES ===== */
:root{
  --color-warm-paper:#F5E6D3;
  --color-dark-ink:#1A1A1A;
  --color-vibrant-orange:#FF6B35;
  --color-metallic-silver:#B0B0B0;
  --color-neon-blue:#00D4FF;
  --color-neon-green:#00FF87;
  --color-deep-gray:#2D2D2D;
  --color-light-gray:#E0E0E0;
  --color-white:#FFFFFF;
  --color-sidebar-bg:#121212;
  --color-content-bg:#222222;
  --color-card-bg:#2A2A2A;
  --color-border-subtle:rgba(255,255,255,0.08);
  --color-border-medium:rgba(255,255,255,0.15);
  --font-headings:Georgia,'Times New Roman',serif;
  --font-body:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;
  --font-data:'Courier New',Consolas,'Liberation Mono',monospace;
  --size-h1:clamp(2rem,5vw,3rem);
  --size-h2:clamp(1.5rem,3.5vw,2.25rem);
  --size-h3:clamp(1.2rem,2.5vw,1.75rem);
  --size-body:1rem;
  --size-small:0.875rem;
  --size-xs:0.75rem;
  --space-unit:1rem;
  --space-xs:0.25rem;
  --space-sm:0.5rem;
  --space-md:1rem;
  --space-lg:1.5rem;
  --space-xl:2rem;
  --space-2xl:3rem;
  --space-3xl:4rem;
  --sidebar-width:260px;
  --sidebar-collapsed:72px;
  --header-top-height:56px;
  --max-width:1280px;
  --shadow-card:0 2px 8px rgba(0,0,0,0.3);
  --radius-sm:2px;
  --radius-md:4px;
  --transition-fast:150ms ease;
  --transition-base:300ms ease;
  --transition-slow:500ms ease;
  --z-skip:1000;
  --z-header:900;
  --z-sidebar:800;
  --z-overlay:700;
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:0.01ms!important;animation-iteration-count:1!important;transition-duration:0.01ms!important;scroll-behavior:auto!important}
}

/* ===== TYPOGRAPHY ===== */
h1,h2,h3,h4,h5,h6{font-family:var(--font-headings);font-weight:700;line-height:1.25;color:var(--color-white);letter-spacing:-0.01em}
h1{font-size:var(--size-h1)}
h2{font-size:var(--size-h2)}
h3{font-size:var(--size-h3)}
h4{font-size:1.25rem}
h5{font-size:1.125rem}
h6{font-size:1rem}
p{margin-bottom:var(--space-md)}
small{font-size:var(--size-small)}
code,pre,.data-text{font-family:var(--font-data)}
a{transition:color var(--transition-fast)}
a:hover{color:var(--color-vibrant-orange)}
::selection{background:var(--color-vibrant-orange);color:var(--color-white)}

/* ===== SR-ONLY & SKIP LINK ===== */
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.skip-link{position:fixed;top:0;left:0;z-index:var(--z-skip);padding:var(--space-sm) var(--space-md);background:var(--color-vibrant-orange);color:var(--color-white);font-size:var(--size-small);font-weight:600;transform:translateY(-120%);transition:transform var(--transition-fast)}
.skip-link:focus{transform:translateY(0);outline:none}

/* ===== BUTTONS ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:var(--space-sm);padding:0.5rem 1.25rem;font-size:var(--size-small);font-weight:600;line-height:1.4;border-radius:var(--radius-sm);transition:all var(--transition-fast);white-space:nowrap;border:1px solid transparent}
.btn:hover{opacity:0.85}
.btn-cta{background:var(--color-vibrant-orange);color:var(--color-white);border-color:var(--color-vibrant-orange)}
.btn-cta:hover{background:#e85d2a;color:var(--color-white)}
.btn-ghost{background:transparent;color:var(--color-warm-paper);border-color:var(--color-border-medium)}
.btn-ghost:hover{background:rgba(255,255,255,0.06);border-color:var(--color-metallic-silver)}
.btn-outline{background:transparent;color:var(--color-vibrant-orange);border-color:var(--color-vibrant-orange)}
.btn-outline:hover{background:var(--color-vibrant-orange);color:var(--color-white)}

/* ===== CONTAINER ===== */
.container{width:100%;max-width:var(--max-width);margin-left:auto;margin-right:auto;padding-left:var(--space-md);padding-right:var(--space-md)}
.container--narrow{max-width:840px}

/* ===== CONTENT SECTION ===== */
.content-section{padding:var(--space-3xl) 0}
.content-section:not(:last-child){border-bottom:1px solid var(--color-border-subtle)}

/* ===== GRID ===== */
.grid{display:grid;gap:var(--space-lg)}
.grid--2{grid-template-columns:repeat(2,1fr)}
.grid--3{grid-template-columns:repeat(3,1fr)}
@media(max-width:768px){.grid--2,.grid--3{grid-template-columns:1fr}}
@media(min-width:769px)and(max-width:1024px){.grid--3{grid-template-columns:repeat(2,1fr)}}

/* ===== DIVIDER ===== */
.divider{width:100%;height:1px;background:var(--color-border-subtle);margin:var(--space-xl) 0}
.divider--gradient{height:2px;background:linear-gradient(90deg,var(--color-vibrant-orange),var(--color-neon-blue),var(--color-neon-green));border-radius:1px}
.divider--angled{height:0;border-top:2px solid var(--color-border-subtle);transform:skewY(-1.5deg);margin:var(--space-2xl) 0}

/* ===== BREADCRUMB ===== */
.breadcrumb{display:flex;flex-wrap:wrap;align-items:center;gap:var(--space-sm);font-size:var(--size-small);color:var(--color-metallic-silver);padding:var(--space-sm) 0}
.breadcrumb ol{display:flex;flex-wrap:wrap;align-items:center;gap:var(--space-sm)}
.breadcrumb li{display:flex;align-items:center;gap:var(--space-sm)}
.breadcrumb li+li::before{content:"/";color:var(--color-border-medium);font-size:var(--size-xs)}
.breadcrumb [aria-current="page"]{color:var(--color-warm-paper);font-weight:600}
.breadcrumb a{color:var(--color-metallic-silver);transition:color var(--transition-fast)}
.breadcrumb a:hover{color:var(--color-vibrant-orange)}

/* ===== CARD ===== */
.card{background:var(--color-card-bg);border:1px solid var(--color-border-subtle);border-radius:var(--radius-md);padding:var(--space-lg);box-shadow:var(--shadow-card);transition:border-color var(--transition-fast),box-shadow var(--transition-fast)}
.card:hover{border-color:var(--color-border-medium);box-shadow:0 4px 16px rgba(0,0,0,0.4)}
.card-title{font-family:var(--font-headings);font-size:1.125rem;font-weight:700;margin-bottom:var(--space-sm);color:var(--color-white)}
.card-text{font-size:var(--size-small);color:var(--color-metallic-silver);line-height:1.5}

/* ===== SCROLL REVEAL ===== */
[data-reveal]{opacity:0;transition:opacity 0.6s ease,transform 0.6s ease}
[data-reveal="fade"]{transform:none}
[data-reveal="up"]{transform:translateY(24px)}
[data-reveal="scale"]{transform:scale(0.96)}
[data-reveal-visible]{opacity:1!important;transform:none!important}

/* ===== HEADER ===== */
.site-header{position:fixed;top:0;left:0;width:100%;height:100vh;z-index:var(--z-header);pointer-events:none;display:flex}
.site-header>*{pointer-events:auto}

/* ===== HEADER SIDEBAR ===== */
.header-sidebar{position:fixed;top:0;left:0;width:var(--sidebar-width);height:100vh;background:var(--color-sidebar-bg);display:flex;flex-direction:column;z-index:var(--z-sidebar);border-right:1px solid var(--color-border-subtle);overflow-y:auto;transition:transform var(--transition-base)}
.header-sidebar::-webkit-scrollbar{width:4px}
.header-sidebar::-webkit-scrollbar-track{background:transparent}
.header-sidebar::-webkit-scrollbar-thumb{background:var(--color-border-medium);border-radius:2px}
.header-brand{display:block;padding:var(--space-xl) var(--space-lg) var(--space-lg);font-family:var(--font-headings);font-size:1.5rem;font-weight:700;color:var(--color-vibrant-orange);letter-spacing:0.04em;transition:opacity var(--transition-fast)}
.header-brand:hover{opacity:0.8;color:var(--color-vibrant-orange)}
.header-nav{padding:var(--space-sm) var(--space-lg) var(--space-lg);flex:1}
.header-nav-list{display:flex;flex-direction:column;gap:var(--space-xs)}
.header-nav-link{display:block;padding:0.5rem 0.625rem;font-size:var(--size-small);font-weight:500;color:var(--color-metallic-silver);border-left:2px solid transparent;transition:all var(--transition-fast);position:relative}
.header-nav-link:hover{color:var(--color-warm-paper);padding-left:0.875rem}
.header-nav-link[aria-current="page"]{color:var(--color-vibrant-orange);border-left-color:var(--color-vibrant-orange);font-weight:600}
.header-nav-link[aria-current="page"]::before{content:"●";position:absolute;left:-1.25rem;top:50%;transform:translateY(-50%);font-size:0.5rem;color:var(--color-vibrant-orange)}
.sidebar-footer{margin-top:auto;padding:var(--space-lg);border-top:1px solid var(--color-border-subtle);position:relative}
.sidebar-footer::before{content:"";position:absolute;top:-2px;left:0;width:100%;height:2px;background:linear-gradient(135deg,var(--color-vibrant-orange),var(--color-neon-blue),var(--color-neon-green));clip-path:polygon(0 0,100% 0,95% 100%,0 100%)}
.sidebar-badge{display:inline-block;padding:0.125rem 0.5rem;font-size:var(--size-xs);font-weight:700;color:var(--color-white);background:var(--color-vibrant-orange);border-radius:var(--radius-sm);margin-bottom:var(--space-sm);animation:pulse-subtle 3s ease-in-out infinite}
@keyframes pulse-subtle{0%,100%{opacity:1}50%{opacity:0.6}}
.sidebar-coord{display:block;font-size:var(--size-xs);color:var(--color-metallic-silver);font-family:var(--font-data);letter-spacing:0.02em}

/* ===== HEADER TOP ===== */
.header-top{position:fixed;top:0;right:0;left:var(--sidebar-width);height:var(--header-top-height);display:flex;align-items:center;justify-content:flex-end;gap:var(--space-md);padding:0 var(--space-lg);background:rgba(18,18,18,0.72);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-bottom:1px solid var(--color-border-subtle);z-index:var(--z-header)}
.nav-toggle{display:none;width:36px;height:36px;flex-direction:column;align-items:center;justify-content:center;gap:5px;border:1px solid var(--color-border-medium);border-radius:var(--radius-sm);background:rgba(255,255,255,0.04);transition:background var(--transition-fast)}
.nav-toggle:hover{background:rgba(255,255,255,0.1)}
.nav-toggle-line{display:block;width:18px;height:2px;background:var(--color-warm-paper);border-radius:1px;transition:all var(--transition-base);transform-origin:center}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2){opacity:0;transform:scaleX(0)}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ===== FOOTER ===== */
.site-footer{background:var(--color-dark-ink);border-top:1px solid var(--color-border-subtle);padding:var(--space-3xl) var(--space-md) var(--space-xl);margin-top:var(--space-3xl)}
.footer-inner{max-width:var(--max-width);margin:0 auto;display:grid;grid-template-columns:1fr 1fr;gap:var(--space-xl) var(--space-2xl)}
.footer-brand{grid-column:1/2}
.footer-logo{font-family:var(--font-headings);font-size:1.25rem;font-weight:700;color:var(--color-vibrant-orange);letter-spacing:0.02em}
.footer-logo:hover{color:var(--color-vibrant-orange);opacity:0.8}
.footer-tagline{font-size:var(--size-small);color:var(--color-metallic-silver);margin-top:var(--space-sm);line-height:1.4}
.footer-links{grid-column:2/3;display:flex;flex-direction:column;align-items:flex-end;gap:var(--space-sm)}
.footer-link{font-size:var(--size-small);color:var(--color-metallic-silver);transition:color var(--transition-fast);padding:0.25rem 0}
.footer-link:hover{color:var(--color-vibrant-orange)}
.footer-contact{grid-column:1/3;display:flex;flex-wrap:wrap;gap:var(--space-md) var(--space-xl);padding-top:var(--space-md);border-top:1px solid var(--color-border-subtle)}
.footer-contact-item{font-size:var(--size-xs);color:var(--color-metallic-silver)}
.footer-contact-item a{color:var(--color-warm-paper);transition:color var(--transition-fast)}
.footer-contact-item a:hover{color:var(--color-vibrant-orange)}
.footer-meta{grid-column:1/3;display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:var(--space-sm);padding-top:var(--space-md);font-size:var(--size-xs);color:var(--color-metallic-silver);border-top:1px solid var(--color-border-subtle)}
.footer-copy{font-family:var(--font-data);letter-spacing:0.02em}
.footer-icp{font-size:var(--size-xs);color:var(--color-metallic-silver)}

/* ===== MAIN CONTENT AREA ===== */
#main-content{min-height:calc(100vh - var(--header-top-height));padding-top:var(--header-top-height);margin-left:var(--sidebar-width);background:var(--color-content-bg);position:relative;z-index:1}
#main-content:focus{outline:none}

/* ===== RESPONSIVE ===== */
@media(max-width:1024px){
  .header-sidebar{transform:translateX(-110%);width:300px;box-shadow:4px 0 24px rgba(0,0,0,0.5)}
  .header-sidebar[data-open]{transform:translateX(0)}
  .header-top{left:0}
  #main-content{margin-left:0;padding-top:var(--header-top-height)}
  .nav-toggle{display:flex}
  .footer-inner{grid-template-columns:1fr}
  .footer-brand,.footer-links{grid-column:1/2}
  .footer-links{align-items:flex-start}
  .footer-contact{grid-column:1/2}
  .footer-meta{grid-column:1/2;flex-direction:column;align-items:flex-start;gap:var(--space-sm)}
}
@media(max-width:768px){
  .header-sidebar{width:100%;max-width:320px}
  .header-top{padding:0 var(--space-md)}
  .header-brand{padding:var(--space-lg) var(--space-md)}
  .header-nav{padding:var(--space-sm) var(--space-md) var(--space-lg)}
  .sidebar-footer{padding:var(--space-md)}
  .site-footer{padding:var(--space-xl) var(--space-md)}
  .footer-contact{flex-direction:column;gap:var(--space-sm)}
}
@media(min-width:1025px){
  .header-sidebar{transform:translateX(0)}
  .header-sidebar[data-open]{transform:translateX(0)}
  .nav-toggle{display:none}
}

/* ===== OVERLAY FOR MOBILE ===== */
@media(max-width:1024px){
  body.nav-open::after{content:"";position:fixed;inset:0;background:rgba(0,0,0,0.5);z-index:var(--z-overlay);pointer-events:auto;backdrop-filter:blur(2px);-webkit-backdrop-filter:blur(2px)}
  body.nav-open{overflow:hidden}
}

/* ===== UTILITY ===== */
.text-orange{color:var(--color-vibrant-orange)}
.text-silver{color:var(--color-metallic-silver)}
.text-white{color:var(--color-white)}
.text-small{font-size:var(--size-small)}
.text-xs{font-size:var(--size-xs)}
.font-mono{font-family:var(--font-data)}
.mt-1{margin-top:var(--space-md)}
.mt-2{margin-top:var(--space-xl)}
.mt-3{margin-top:var(--space-2xl)}
.mb-1{margin-bottom:var(--space-md)}
.mb-2{margin-bottom:var(--space-xl)}
.mb-3{margin-bottom:var(--space-2xl)}
.p-1{padding:var(--space-md)}
.p-2{padding:var(--space-xl)}
.p-3{padding:var(--space-2xl)}
.flex{display:flex}
.flex-col{flex-direction:column}
.items-center{align-items:center}
.justify-between{justify-content:space-between}
.gap-1{gap:var(--space-md)}
.gap-2{gap:var(--space-xl)}