/* ============================================
   MAIN STYLES — Immersive 3D Web Experience
   Palette: #050507 · #1e90ff · #d4af37 · #f0f0f0
   ============================================ */

/* --- Base --- */
*, *::before, *::after { box-sizing: border-box; }

html, body {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: #02040a;
    background-size: cover;
    background-position: center center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    color: var(--text-primary);
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

/* --- Canvas (full screen, base layer) --- */
#canvas {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    display: block;
}

/* ============================================
   HUD — floating top bar
   ============================================ */
.hud {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 28px;
    z-index: var(--z-navbar);
    pointer-events: none;
}

.hud > * { pointer-events: auto; }

.hud-actions {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Language Switcher - Dropdown Combobox */
.language-switcher {
    position: fixed;
    right: 20px;
    bottom: 20px;
    display: inline-block;
    z-index: calc(var(--z-navbar) + 20);
}

.lang-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    width: auto;
    height: 40px;
    padding: 0 12px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.04);
    color: var(--accent-white);
    cursor: pointer;
    font-size: 12px;
    font-weight: 700;
    transition: all 0.2s ease;
    backdrop-filter: blur(4px);
}

.lang-toggle:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.24);
}

.lang-flag {
    width: 20px;
    height: 15px;
    border-radius: 2px;
    flex-shrink: 0;
}

.lang-dropdown-arrow {
    font-size: 10px;
    color: var(--text-secondary);
    transition: transform 0.2s ease;
    display: none;
}

.language-switcher[aria-expanded="true"] .lang-dropdown-arrow {
    transform: scaleY(-1);
}

.lang-options {
    position: absolute;
    bottom: calc(100% + 6px);
    right: 0;
    margin-top: 0;
    min-width: 180px;
    background: rgba(5, 7, 10, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 8px;
    padding: 4px;
    display: none;
    flex-direction: column;
    gap: 2px;
    backdrop-filter: blur(8px);
    z-index: 1000;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.language-switcher[aria-expanded="true"] .lang-options {
    display: flex;
}

.lang-option {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px;
    cursor: pointer;
    border-radius: 4px;
    font-size: 12px;
    color: var(--accent-white);
    transition: all 0.2s ease;
}

.lang-option:hover {
    background: rgba(30, 144, 255, 0.15);
}

.lang-option[aria-selected="true"] {
    background: rgba(30, 144, 255, 0.25);
    border-left: 2px solid rgba(30, 144, 255, 0.6);
    padding-left: 10px;
}

.lang-option svg {
    width: 20px;
    height: 15px;
    border-radius: 2px;
    flex-shrink: 0;
}

/* Logo */
.hud-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    color: var(--accent-white);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    opacity: 0.9;
    transition: opacity 0.2s;
}
.hud-logo:hover { opacity: 1; }
.hud-logo span {
    background: linear-gradient(135deg, var(--accent-gold), var(--accent-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: none;
}

/* Menu button */
.menu-btn {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: 8px;
    cursor: pointer;
    padding: 0 10px;
    transition: background 0.2s, border-color 0.2s;
}
.menu-btn:hover {
    background: rgba(30,144,255,0.12);
    border-color: rgba(30,144,255,0.4);
}
.menu-btn-line {
    display: block;
    width: 100%;
    height: 1.5px;
    background: var(--accent-white);
    border-radius: 2px;
    transition: transform 0.3s, opacity 0.3s;
}
.menu-btn.open .menu-btn-line:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.menu-btn.open .menu-btn-line:nth-child(2) { opacity: 0; transform: scaleX(0); }
.menu-btn.open .menu-btn-line:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ============================================
   SIDE PANEL
   ============================================ */
.side-panel-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.6);
    backdrop-filter: blur(4px);
    z-index: calc(var(--z-sidepanel) - 1);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s ease;
}
.side-panel-backdrop.visible {
    opacity: 1;
    pointer-events: auto;
}

.side-panel {
    position: fixed;
    top: 0;
    right: 0;
    width: 320px;
    height: 100%;
    background: rgba(8, 9, 14, 0.95);
    border-left: 1px solid rgba(30, 144, 255, 0.15);
    backdrop-filter: blur(24px);
    z-index: var(--z-sidepanel);
    display: flex;
    flex-direction: column;
    transform: translateX(100%);
    transition: transform 0.45s cubic-bezier(0.77,0,0.175,1);
    padding: 0 0 40px;
}
.side-panel.open {
    transform: translateX(0);
}

.side-panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 28px 20px;
    border-bottom: 1px solid rgba(255,255,255,0.05);
}
.side-panel-label {
    font-size: 0.65rem;
    letter-spacing: 0.25em;
    color: var(--accent-blue);
    font-weight: 600;
}
.side-panel-close {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.04);
    border: 1px solid rgba(255,255,255,0.07);
    border-radius: 6px;
    color: var(--text-secondary);
    font-size: 0.8rem;
    cursor: pointer;
    transition: color 0.2s, border-color 0.2s;
}
.side-panel-close:hover {
    color: var(--accent-white);
    border-color: rgba(255,255,255,0.2);
}

/* Nav items */
.side-nav {
    list-style: none;
    flex: 1;
    padding: 24px 0;
}

.side-nav-group {
    margin-bottom: 8px;
}

.side-nav-group-toggle {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 22px 6px 28px;
    background: transparent;
    border: 0;
    cursor: pointer;
}

.side-nav-satellite {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0;
}

.side-nav-satellite .side-nav-item {
    flex: 1;
    margin: 0;
    padding: 14px 28px;
}

.side-nav-expand-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 0;
    cursor: pointer;
    padding: 14px 20px;
    color: var(--accent-blue);
    font-size: 1.2rem;
    transition: transform 0.2s ease;
}

.side-nav-expand-btn:hover {
    color: var(--accent-white);
}

.side-nav-group[aria-expanded="true"] .side-nav-expand-btn .expand-arrow {
    transform: rotate(90deg);
    display: inline-block;
    transition: transform 0.2s ease;
}

.side-nav-group-label {
    font-size: 0.62rem;
    letter-spacing: 0.14em;
    color: var(--accent-blue);
    text-transform: uppercase;
    opacity: 0.9;
}

.tree-caret {
    color: var(--accent-blue);
    font-size: 0.72rem;
    transition: transform 0.2s ease;
}

.side-nav-group[aria-expanded="true"] .tree-caret {
    transform: rotate(90deg);
}

.side-subnav {
    list-style: none;
    margin: 0;
    padding: 0 0 0 12px;
    border-left: 1px solid rgba(30, 144, 255, 0.2);
    margin-left: 28px;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.25s ease, opacity 0.2s ease;
}

.side-nav-group[aria-expanded="true"] .side-subnav {
    max-height: 400px;
    opacity: 1;
}

.tree-item {
    padding: 9px 18px;
    margin-right: 18px;
    border-radius: 8px;
    gap: 10px;
}

.tree-item .side-nav-title {
    font-size: 0.72rem;
    letter-spacing: 0.08em;
}
.side-nav-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 14px 28px;
    text-decoration: none;
    color: var(--text-secondary);
    transition: color 0.25s, background 0.25s;
    position: relative;
    cursor: pointer;
}
.side-nav-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--accent-blue);
    transform: scaleY(0);
    transition: transform 0.25s;
}
.side-nav-item:hover,
.side-nav-item.active {
    color: var(--accent-white);
    background: rgba(30, 144, 255, 0.06);
}
.side-nav-item:hover::before,
.side-nav-item.active::before {
    transform: scaleY(1);
}
.side-nav-index {
    font-size: 0.6rem;
    letter-spacing: 0.1em;
    color: var(--accent-blue);
    opacity: 0.7;
    font-variant-numeric: tabular-nums;
    min-width: 20px;
}
.side-nav-title {
    flex: 1;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}
.side-nav-arrow {
    font-size: 0.8rem;
    opacity: 0;
    transform: translateX(-4px);
    transition: opacity 0.2s, transform 0.2s;
    color: var(--accent-blue);
}
.side-nav-item:hover .side-nav-arrow,
.side-nav-item.active .side-nav-arrow {
    opacity: 1;
    transform: translateX(0);
}

.side-panel-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 28px;
    font-size: 0.6rem;
    letter-spacing: 0.2em;
    color: var(--text-muted);
    text-transform: uppercase;
}

.side-panel-social-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 8px;
    color: rgba(188, 214, 235, 0.86);
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.03);
    text-decoration: none;
    transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.side-panel-social-link:hover,
.side-panel-social-link:focus-visible {
    color: var(--accent-blue);
    border-color: rgba(30, 144, 255, 0.45);
    background: rgba(30, 144, 255, 0.1);
}

/* ============================================
   CONTENT AREA
   ============================================ */
.content-area {
    position: fixed;
    inset: 0;
    z-index: 10;
    --origin-x: 50vw;
    --origin-y: 50vh;
    background: linear-gradient(
        180deg,
        rgba(5, 5, 7, 0.0) 0%,
        rgba(9, 18, 10, 0.32) 12%,
        rgba(8, 14, 9, 0.48) 100%
    );
    overflow-y: auto;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.5s ease;
    scrollbar-width: thin;
    scrollbar-color: rgba(30,144,255,0.3) transparent;
}

.preview-section {
    display: grid;
    place-items: center;
    min-height: min(62vh, 560px);
}

.preview-card-single {
    width: min(560px, calc(100vw - 42px));
    padding: 28px;
    border-radius: 14px;
    border: 1px solid rgba(255, 255, 255, 0.14);
    background: rgba(7, 11, 18, 0.82);
    backdrop-filter: blur(10px);
    text-align: center;
    box-shadow: 0 14px 40px rgba(0, 0, 0, 0.35);
}

.preview-enter-btn {
    margin-top: 10px;
}
.content-area::-webkit-scrollbar { width: 4px; }
.content-area::-webkit-scrollbar-thumb {
    background: rgba(30,144,255,0.3);
    border-radius: 2px;
}
.content-area.active {
    opacity: 1;
    pointer-events: auto;
}

.content-area.home-overlay {
    background: linear-gradient(
        90deg,
        rgba(5, 5, 7, 0.86) 0%,
        rgba(5, 5, 7, 0.58) 34%,
        rgba(5, 5, 7, 0.14) 62%,
        rgba(5, 5, 7, 0) 100%
    );
    pointer-events: none;
    overflow: hidden;
}

.content-area.home-overlay .content-wrapper {
    max-width: min(720px, 58vw);
    margin-left: clamp(20px, 4vw, 72px);
    margin-right: auto;
    padding-top: 108px;
    pointer-events: none;
}

.content-area.home-overlay .section-title {
    line-height: 1.22;
    padding-bottom: 0.12em;
}

.content-area.home-overlay a,
.content-area.home-overlay button,
.content-area.home-overlay .button,
.content-area.home-overlay .intro-stack,
.content-area.home-overlay .home-scene-note,
.content-area.home-overlay .orbit-section,
.content-area.home-overlay .feature-card {
    pointer-events: auto;
}

.home-scene-note {
    position: absolute;
    left: clamp(20px, 4vw, 72px);
    bottom: clamp(18px, 3vw, 34px);
    width: min(420px, calc(100vw - 40px));
    padding: 12px 14px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    background: rgba(5, 8, 12, 0.46);
    backdrop-filter: blur(12px);
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.22);
}

.home-scene-note.is-compact {
    right: auto;
    width: min(250px, calc(100vw - 92px));
    max-width: calc(100vw - 92px);
    padding: 8px 9px;
    border-radius: 10px;
}

.home-scene-note.is-hidden {
    display: none;
}

.home-scene-note__eyebrow {
    display: inline-block;
    margin-bottom: 6px;
    font-size: 0.68rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: rgba(180, 220, 255, 0.82);
}

.home-scene-note__text {
    margin: 0;
    font-size: 0.84rem;
    line-height: 1.5;
    color: rgba(240, 248, 255, 0.88);
}

.home-scene-note__meta {
    margin: 6px 0 0;
    font-size: 0.72rem;
    line-height: 1.45;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: rgba(188, 214, 235, 0.68);
}

.home-scene-note__link {
    display: inline-flex;
    align-items: center;
    margin-top: 8px;
    font-size: 0.76rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-blue);
    text-decoration: none;
}

.home-scene-note__link:hover,
.home-scene-note__link:focus-visible {
    color: var(--accent-gold);
}

.home-scene-note.is-compact .home-scene-note__eyebrow {
    margin-bottom: 4px;
    font-size: 0.6rem;
    letter-spacing: 0.14em;
}

.home-scene-note.is-compact .home-scene-note__text {
    font-size: 0.76rem;
    line-height: 1.4;
}

.home-scene-note.is-compact .home-scene-note__meta {
    margin-top: 4px;
    font-size: 0.66rem;
    line-height: 1.35;
}

.home-scene-note.is-compact .home-scene-note__link {
    margin-top: 6px;
    font-size: 0.68rem;
}

.content-wrapper {
    min-height: 100%;
    max-width: min(980px, 74vw);
    margin: 0 auto;
    padding: 100px 48px 80px;
    transform-origin: var(--origin-x) var(--origin-y);
}

.content-area[data-page-type="satellite"] .content-wrapper {
    max-width: min(1100px, 84vw);
    padding-left: 56px;
    padding-right: 56px;
}

.content-area[data-page-type="detail"] .content-wrapper {
    max-width: min(1180px, 84vw);
}

.content-area.origin-left .content-wrapper {
    margin-left: clamp(20px, 4vw, 72px);
    margin-right: auto;
}

.content-area.origin-right .content-wrapper {
    margin-left: auto;
    margin-right: clamp(20px, 4vw, 72px);
}

.content-area.origin-center .content-wrapper {
    margin-left: auto;
    margin-right: auto;
}

.content-area.text-born .content-wrapper {
    animation: bornFromSatellite 0.7s cubic-bezier(0.19, 1, 0.22, 1) both;
}

@keyframes bornFromSatellite {
    0% {
        opacity: 0;
        transform: translate3d(0, 0, 0) scale(0.84);
        filter: blur(8px);
        clip-path: circle(0% at var(--origin-x) var(--origin-y));
    }
    50% {
        opacity: 0.9;
        filter: blur(1px);
        clip-path: circle(28% at var(--origin-x) var(--origin-y));
    }
    100% {
        opacity: 1;
        transform: translate3d(0, 0, 0) scale(1);
        filter: blur(0);
        clip-path: circle(140% at var(--origin-x) var(--origin-y));
    }
}

/* --- Typography --- */
.section-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    letter-spacing: -0.01em;
    line-height: 1.2;
    background: linear-gradient(135deg, var(--accent-white) 0%, var(--accent-blue) 60%, var(--accent-gold) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
    padding-bottom: 0.08em;
}

.section-subtitle {
    font-size: 0.85rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent-blue);
    opacity: 0.8;
    margin-bottom: 48px;
}

.section {
    margin-bottom: 64px;
}

/* --- Cards --- */
.feature-card,
.project-card,
.app-card {
    background: rgba(255,255,255,0.02);
    border: 1px solid rgba(255,255,255,0.07);
    border-radius: 12px;
    padding: 28px;
    transition: background 0.3s, border-color 0.3s, transform 0.3s;
}
.feature-card:hover,
.project-card:hover,
.app-card:hover {
    background: rgba(30, 144, 255, 0.05);
    border-color: rgba(30, 144, 255, 0.25);
    transform: translateY(-4px);
}

/* --- Badges --- */
.badge {
    display: inline-block;
    padding: 3px 10px;
    background: rgba(30, 144, 255, 0.1);
    border: 1px solid rgba(30, 144, 255, 0.2);
    border-radius: 100px;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    color: var(--accent-blue);
}
.badge.accent {
    background: rgba(212, 175, 55, 0.1);
    border-color: rgba(212, 175, 55, 0.25);
    color: var(--accent-gold);
}

/* --- Buttons --- */
.button {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    background: transparent;
    border: 1px solid rgba(30, 144, 255, 0.4);
    border-radius: 8px;
    color: var(--accent-blue);
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    text-decoration: none;
    cursor: pointer;
    transition: background 0.25s, border-color 0.25s, color 0.25s, transform 0.2s;
}
.button:hover {
    background: rgba(30, 144, 255, 0.12);
    border-color: rgba(30, 144, 255, 0.7);
    color: var(--accent-white);
    transform: translateY(-1px);
}
.button-primary {
    background: linear-gradient(135deg, rgba(30,144,255,0.2), rgba(212,175,55,0.1));
    border-color: rgba(30,144,255,0.5);
    color: var(--accent-white);
}
.button-secondary {
    border-color: rgba(212,175,55,0.3);
    color: var(--accent-gold);
}
.button-secondary:hover {
    background: rgba(212,175,55,0.08);
    border-color: rgba(212,175,55,0.6);
}

/* --- Back button --- */
.back-btn {
    position: fixed;
    top: 16px;
    left: 28px;
    z-index: 20;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: rgba(8,9,14,0.8);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    cursor: pointer;
    backdrop-filter: blur(12px);
    transition: color 0.2s, border-color 0.2s;
}
.back-btn:hover {
    color: var(--accent-white);
    border-color: rgba(255,255,255,0.25);
}

/* ============================================
   LOADER
   ============================================ */
.loader {
    position: fixed;
    inset: 0;
    z-index: 999;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 24px;
    transition: opacity 0.6s ease;
}
.loader.hidden {
    opacity: 0;
    pointer-events: none;
    visibility: hidden;
}
.loader-ring {
    width: 44px;
    height: 44px;
    border: 1.5px solid rgba(30, 144, 255, 0.15);
    border-top-color: var(--accent-blue);
    border-radius: 50%;
    animation: spin 0.9s linear infinite;
}
.loader-text {
    font-size: 0.65rem;
    letter-spacing: 0.35em;
    color: var(--text-muted);
    text-transform: uppercase;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}