/* ═══════════════════════════════════════════════════════════
   KODASKILLS DESIGN SYSTEM — CSS Variables
   ═══════════════════════════════════════════════════════════ */

:root {
    --color-primary: #44d8f1;
    --color-primary-dim: #2dcae2;
    --color-primary-fixed: #a1efff;
    --color-primary-container: #004e59;
    --color-on-primary: #004751;
    --color-inverse-primary: #006977;

    --color-tertiary: #ffc563;
    --color-tertiary-dim: #eda600;
    --color-tertiary-container: #feb300;

    --color-secondary: #93a0a7;
    --color-secondary-container: #313d43;

    --color-surface: #0e0e0e;
    --color-surface-dim: #0e0e0e;
    --color-surface-bright: #2b2c2c;
    --color-surface-variant: #252626;
    --color-surface-container-lowest: #000000;
    --color-surface-container-low: #131313;
    --color-surface-container: #191a1a;
    --color-surface-container-high: #1f2020;
    --color-surface-container-highest: #252626;

    --color-on-surface: #e7e5e5;
    --color-on-surface-variant: #acabaa;
    --color-background: #0e0e0e;

    --color-outline: #767575;
    --color-outline-variant: #484848;

    --color-error: #ee7d77;
    --color-error-container: #7f2927;

    --color-inverse-surface: #fcf9f8;
    --color-inverse-on-surface: #565555;
}

:root.light {
    --color-primary: #006876;
    --color-primary-dim: #004e59;
    --color-primary-fixed: #006876;
    --color-primary-container: #00bcd4;
    --color-on-primary: #ffffff;
    --color-inverse-primary: #44d8f1;

    --color-tertiary: #7c5800;
    --color-tertiary-dim: #5e4000;
    --color-tertiary-container: #ffdea0;

    --color-secondary: #565f64;
    --color-secondary-container: #bbebf5;

    --color-surface: #f9f9f9;
    --color-surface-dim: #e8e8e8;
    --color-surface-bright: #f9f9f9;
    --color-surface-variant: #e8e8e8;
    --color-surface-container-lowest: #ffffff;
    --color-surface-container-low: #f3f3f3;
    --color-surface-container: #ededed;
    --color-surface-container-high: #e7e7e7;
    --color-surface-container-highest: #e2e2e2;

    --color-on-surface: #1a1c1c;
    --color-on-surface-variant: #4a4e4e;
    --color-background: #f9f9f9;

    --color-outline: #787c7c;
    --color-outline-variant: #bbc9cc;

    --color-error: #ba1a1a;
    --color-error-container: #ffdad6;

    --color-inverse-surface: #2f2d2d;
    --color-inverse-on-surface: #f0edec;
}

/* ═══════════════════════════════════════════════════════════
   BASE RESET & GLOBAL STYLES
   ═══════════════════════════════════════════════════════════ */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: "Inter", system-ui, -apple-system, sans-serif;
    background-color: var(--color-background);
    background-image: radial-gradient(circle, var(--color-outline-variant) 1px, transparent 1px);
    background-size: 24px 24px;
    color: var(--color-on-surface);
    line-height: 1.6;
    min-height: 100vh;
}

.font-headline { font-family: "Space Grotesk", sans-serif; }
.font-mono { font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace; }

/* ═══════════════════════════════════════════════════════════
   LAYOUT
   ═══════════════════════════════════════════════════════════ */

.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main {
    margin-top: 64px;
    flex: 1;
}

/* ═══════════════════════════════════════════════════════════
   HEADER
   ═══════════════════════════════════════════════════════════ */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 64px;
    background: transparent;
    z-index: 1000;
    display: flex;
    align-items: center;
    padding: 0 24px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.header.scrolled {
    background-color: color-mix(in srgb, var(--color-surface) 85%, transparent);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-outline-variant);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

.header-content {
    max-width: 1280px;
    width: 100%;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-family: "Space Grotesk", sans-serif;
    font-size: 28px;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    line-height: 1;
}

.nav {
    display: flex;
    align-items: center;
    gap: 16px;
}

.nav-link {
    font-family: "Space Grotesk", sans-serif;
    font-size: 13px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-on-surface-variant) !important;
    text-decoration: none !important;
    padding: 8px 12px;
    position: relative;
    transition: color 0.2s;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 12px;
    right: 12px;
    height: 2px;
    background-color: var(--color-primary);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-link:hover { color: var(--color-primary) !important; }
.nav-link.active { color: var(--color-primary) !important; }
.nav-link.active::after { transform: scaleX(1); }

.nav-dot {
    color: var(--color-outline);
    font-size: 8px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* ═══════════════════════════════════════════════════════════
   BUTTONS
   ═══════════════════════════════════════════════════════════ */

.btn {
    font-family: "Space Grotesk", sans-serif;
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 10px 20px;
    border: none;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.2s;
    position: relative;
    overflow: hidden;
}

.btn svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn:hover svg { transform: scale(1.15); }
.btn-primary svg { fill: currentColor; }

.btn-outlined svg,
.btn-outlined-primary svg {
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.btn-primary { background-color: var(--color-primary); color: var(--color-on-primary); }
.btn-primary:hover { background-color: var(--color-primary-dim); }
.btn-primary:hover svg { animation: btn-icon-bounce 0.4s ease; }

.btn-outlined { background-color: transparent; border: 1px solid var(--color-outline); color: var(--color-on-surface); }
.btn-outlined:hover { border-color: var(--color-primary); color: var(--color-primary); }
.btn-outlined:hover svg { animation: btn-icon-rotate 0.4s ease; }

.btn-outlined-primary { background-color: transparent; border: 1px solid var(--color-primary); color: var(--color-primary); }
.btn-outlined-primary:hover { background-color: var(--color-primary-container); }
.btn-outlined-primary:hover svg { animation: btn-icon-slide 0.4s ease; }

@keyframes btn-icon-bounce {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.3); }
}

@keyframes btn-icon-rotate {
    0% { transform: rotate(0deg) scale(1); }
    100% { transform: rotate(15deg) scale(1.1); }
}

@keyframes btn-icon-slide {
    0% { transform: translateX(0); }
    50% { transform: translateX(3px); }
    100% { transform: translateX(0); }
}

/* ═══════════════════════════════════════════════════════════
   THEME TOGGLE
   ═══════════════════════════════════════════════════════════ */

.theme-toggle {
    background: none;
    border: 1px solid var(--color-outline-variant);
    color: var(--color-on-surface-variant);
    padding: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    transition: all 0.2s;
}

.theme-toggle:hover { border-color: var(--color-primary); color: var(--color-primary); }
.theme-toggle svg { width: 18px; height: 18px; }

/* ═══════════════════════════════════════════════════════════
   SECTION HEADERS
   ═══════════════════════════════════════════════════════════ */

.section-header { margin-bottom: 48px; }

.section-label {
    font-family: "Space Grotesk", sans-serif;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    color: var(--color-primary);
    margin-bottom: 16px;
}

.section-title {
    font-family: "Space Grotesk", sans-serif;
    font-size: clamp(32px, 4vw, 48px);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.02em;
    color: var(--color-on-surface);
    margin-bottom: 16px;
}

.section-desc {
    font-family: "Inter", sans-serif;
    font-size: 16px;
    line-height: 1.75;
    color: var(--color-on-surface-variant);
    max-width: 640px;
}

/* ═══════════════════════════════════════════════════════════
   DEMO SECTION
   ═══════════════════════════════════════════════════════════ */

.demo-section { padding: 64px 24px; }

.demo-container {
    max-width: 1280px;
    margin: 0 auto;
}

.demo-description {
    margin-bottom: 32px;
    padding: 24px;
    background-color: var(--color-surface-container-low);
    border: 1px solid var(--color-outline-variant);
    border-left: 3px solid var(--color-primary);
}

.demo-description--spaced { margin-top: 32px; }

.demo-description h4 {
    font-family: "Space Grotesk", sans-serif;
    font-size: 16px;
    font-weight: 600;
    color: var(--color-on-surface);
    margin-bottom: 8px;
}

.demo-description p {
    font-family: "Inter", sans-serif;
    font-size: 14px;
    line-height: 1.6;
    color: var(--color-on-surface-variant);
}

/* ═══════════════════════════════════════════════════════════
   DEMO CANVAS
   ═══════════════════════════════════════════════════════════ */

.demo-canvas {
    position: relative;
    background-color: var(--color-surface-container-lowest);
    border: 1px solid var(--color-outline-variant);
    overflow: hidden;
    height: 700px;
}

#bevy-canvas,
#bevy-canvas-3d {
    width: 100%;
    height: 700px;
    display: block;
    outline: none;
}

#bevy-canvas:focus,
#bevy-canvas-3d:focus {
    outline: none;
}

/* ═══════════════════════════════════════════════════════════
   WASM LOADER
   ═══════════════════════════════════════════════════════════ */

#wasm-loader {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-surface-container-lowest);
    z-index: 10;
    transition: opacity 0.5s ease;
}

#wasm-loader.hidden {
    opacity: 0;
    pointer-events: none;
}

.loader-frame {
    position: relative;
    padding: 48px 56px;
    border: 1px solid var(--color-outline-variant);
    background-color: var(--color-surface-container);
    overflow: hidden;
    min-width: 320px;
    text-align: center;
}

.loader-frame::before {
    content: '';
    position: absolute;
    inset: 0;
    background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 2px,
        rgba(68, 216, 241, 0.03) 2px,
        rgba(68, 216, 241, 0.03) 4px
    );
    pointer-events: none;
}

.loader-accent {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--color-primary);
    animation: loader-scan 2s ease-in-out infinite;
}

@keyframes loader-scan {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

.loader-badge {
    display: inline-block;
    font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 0.2em;
    color: var(--color-primary);
    padding: 4px 10px;
    border: 1px solid var(--color-primary);
    margin-bottom: 20px;
    text-transform: uppercase;
}

.loader-title-text {
    font-family: "Space Grotesk", sans-serif;
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-on-surface);
    margin-bottom: 4px;
}

.loader-sub {
    font-family: "Inter", sans-serif;
    font-size: 12px;
    color: var(--color-on-surface-variant);
    margin-bottom: 32px;
}

.loader-bar-track {
    position: relative;
    height: 2px;
    background-color: var(--color-outline-variant);
    margin-bottom: 16px;
    overflow: hidden;
}

.loader-bar {
    position: absolute;
    top: 0;
    height: 100%;
    width: 40%;
    background-color: var(--color-primary);
    animation: loader-indeterminate 1.6s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}

@keyframes loader-indeterminate {
    0%   { left: -40%; }
    100% { left: 140%; }
}

.loader-status {
    font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
    font-size: 11px;
    color: var(--color-on-surface-variant);
    letter-spacing: 0.05em;
}

/* ═══════════════════════════════════════════════════════════
   BACK LINK
   ═══════════════════════════════════════════════════════════ */

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: "Space Grotesk", sans-serif;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-on-surface-variant);
    text-decoration: none;
    margin-bottom: 40px;
    transition: color 0.2s;
}

.back-link svg {
    width: 16px;
    height: 16px;
    fill: currentColor;
    transition: transform 0.2s;
}

.back-link:hover { color: var(--color-primary); }
.back-link:hover svg { transform: translateX(-3px); }

/* ═══════════════════════════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════════════════════════ */

.footer {
    border-top: 1px solid var(--color-outline-variant);
    padding: 64px 24px 32px;
}

.footer-content {
    max-width: 1280px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 64px;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.footer-logo {
    font-family: "Space Grotesk", sans-serif;
    font-size: 32px;
    font-weight: 700;
    color: var(--color-primary);
}

.footer-tagline {
    font-family: "Inter", sans-serif;
    font-size: 14px;
    color: var(--color-on-surface-variant);
}

.footer-nav {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.footer-nav-column h4 {
    font-family: "Space Grotesk", sans-serif;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-on-surface);
    margin-bottom: 16px;
}

.footer-nav-column a {
    display: block;
    font-family: "Inter", sans-serif;
    font-size: 14px;
    color: var(--color-on-surface-variant);
    text-decoration: none;
    padding: 4px 0;
    transition: color 0.2s;
}

.footer-nav-column a:hover { color: var(--color-primary); }

.footer-bottom {
    max-width: 1280px;
    margin: 48px auto 0;
    padding-top: 32px;
    border-top: 1px solid var(--color-outline-variant);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-copyright {
    font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
    font-size: 12px;
    color: var(--color-on-surface-variant);
}

.footer-badges { display: flex; gap: 12px; }
.footer-badges img { height: 20px; }

/* ═══════════════════════════════════════════════════════════
   RESPONSIVE — shared rules
   ═══════════════════════════════════════════════════════════ */

@media (max-width: 1024px) {
    .footer-content {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .footer-nav {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .nav { display: none; }

    .demo-canvas { height: 500px; }

    #bevy-canvas,
    #bevy-canvas-3d { height: 500px; }

    .demo-description { padding: 16px; margin-bottom: 16px; }
    .demo-description h4 { font-size: 14px; }
    .demo-description p { font-size: 13px; }

    .footer-nav { grid-template-columns: 1fr; gap: 24px; }
    .footer-bottom { flex-direction: column; gap: 16px; align-items: flex-start; }
}

/* ═══════════════════════════════════════════════════════════
   PAGE: INDEX
   ═══════════════════════════════════════════════════════════ */

.page-index .demo-section { background-color: var(--color-surface-container); }

.page-index .hero {
    position: relative;
    min-height: 550px;
    padding: 80px 24px 64px;
}

.page-index .hero-content {
    position: relative;
    z-index: 1;
    max-width: 1280px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.page-index .hero-text { display: flex; flex-direction: column; justify-content: center; }

.page-index .hero-visual { display: flex; align-items: center; justify-content: center; }

.page-index .hero-visual img {
    width: 100%;
    max-width: 100%;
    display: block;
    filter: drop-shadow(0 8px 32px rgba(0, 0, 0, 0.5));
}

.page-index .hero-actions { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }

.page-index .hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background-color: var(--color-primary-container);
    border-left: 3px solid var(--color-primary);
    margin-bottom: 24px;
}

.page-index .hero-badge-dot {
    width: 8px;
    height: 8px;
    background-color: var(--color-primary);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(1.2); }
}

.page-index .hero-badge-text {
    font-family: "Space Grotesk", sans-serif;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-primary);
}

.page-index .hero-title {
    font-family: "Space Grotesk", sans-serif;
    font-size: clamp(48px, 8vw, 96px);
    font-weight: 700;
    line-height: 1;
    letter-spacing: -0.03em;
    color: var(--color-on-surface);
    margin-bottom: 16px;
}

.page-index .hero-title-accent { color: var(--color-primary); }

.page-index .hero-subtitle {
    font-family: "Inter", sans-serif;
    font-size: 18px;
    line-height: 1.75;
    color: var(--color-on-surface-variant);
    max-width: 720px;
    margin-bottom: 32px;
}

.page-index .hero-meta { display: flex; flex-wrap: wrap; gap: 24px; margin-top: 32px; }
.page-index .hero-meta-item { display: flex; flex-direction: column; gap: 4px; }

.page-index .hero-meta-label {
    font-family: "Space Grotesk", sans-serif;
    font-size: 11px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-on-surface-variant);
}

.page-index .hero-meta-value {
    font-family: "Inter", sans-serif;
    font-size: 16px;
    font-weight: 500;
    color: var(--color-on-surface);
}

.page-index .hero-meta-value a { color: var(--color-primary); text-decoration: none; }
.page-index .hero-meta-value a:hover { text-decoration: underline; }

.page-index .features-section { padding: 64px 24px; }
.page-index .features-container { max-width: 1280px; margin: 0 auto; }

.page-index .bento-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0;
    margin-top: 64px;
}

.page-index .bento-card {
    padding: 32px;
    border: 1px solid var(--color-outline-variant);
    background-color: var(--color-surface-container);
    position: relative;
    display: flex;
    flex-direction: column;
}

.page-index .bento-card:not(:last-child) { border-right: none; }

.page-index .bento-card-header { display: flex; align-items: center; gap: 16px; margin-bottom: 16px; }

.page-index .bento-card-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: transparent;
    margin-bottom: 16px;
    font-size: 28px;
}

.page-index .bento-card-title {
    font-family: "Space Grotesk", sans-serif;
    font-size: 18px;
    font-weight: 600;
    color: var(--color-on-surface);
    margin-bottom: 12px;
}

.page-index .bento-card-desc {
    font-family: "Inter", sans-serif;
    font-size: 14px;
    line-height: 1.6;
    color: var(--color-on-surface-variant);
    margin-bottom: 16px;
}

.page-index .bento-card-code {
    font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
    font-size: 12px;
    line-height: 1.8;
    color: var(--color-primary);
    margin-top: auto;
    padding: 12px;
    background-color: var(--color-surface-container-lowest);
    border: 1px solid var(--color-outline-variant);
}

.page-index .controls-section { padding: 64px 24px; background-color: var(--color-surface-container); }
.page-index .controls-container { max-width: 1280px; margin: 0 auto; }

.page-index .controls-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
    margin-top: 64px;
}

.page-index .control-card {
    padding: 32px;
    border: 1px solid var(--color-outline-variant);
    background-color: var(--color-surface);
}

.page-index .control-card:not(:last-child) { border-right: none; }

.page-index .control-key {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 12px;
    font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
    font-size: 15px;
    font-weight: 700;
    letter-spacing: 0.05em;
    color: var(--color-on-surface);
    background-color: var(--color-surface-container-high);
    border: 1px solid var(--color-outline);
    border-bottom: 3px solid var(--color-outline);
    border-radius: 6px;
    box-shadow: 0 2px 0 var(--color-outline-variant);
    margin-bottom: 20px;
    user-select: none;
}

.page-index .control-action {
    font-family: "Space Grotesk", sans-serif;
    font-size: 16px;
    font-weight: 500;
    color: var(--color-on-surface);
}

@media (max-width: 1024px) {
    .page-index .bento-grid { grid-template-columns: repeat(2, 1fr); }
    .page-index .bento-card:nth-child(even) { border-left: 1px solid var(--color-outline-variant); }
    .page-index .controls-grid { grid-template-columns: repeat(2, 1fr); }
    .page-index .control-card:nth-child(even) { border-left: 1px solid var(--color-outline-variant); }
}

@media (max-width: 768px) {
    .page-index .hero-content { grid-template-columns: 1fr; gap: 48px; }
    .page-index .hero-visual { order: -1; }
    .page-index .hero-actions { margin-bottom: 32px; }
    .page-index .bento-grid { grid-template-columns: 1fr; }
    .page-index .bento-card { border-left: 1px solid var(--color-outline-variant) !important; }
    .page-index .controls-grid { grid-template-columns: 1fr; }
    .page-index .control-card { border-left: 1px solid var(--color-outline-variant) !important; }
}

/* ═══════════════════════════════════════════════════════════
   PAGE: 3D
   ═══════════════════════════════════════════════════════════ */

.page-3d .main { display: flex; flex-direction: column; }
.page-3d .demo-section { flex: 1; }