/* ==========================================
   CINEMATIC LANDING PAGE — ENVIRONMENTAL LIGHTING
   Apple-level premium design system
   ========================================== */

/* ==========================================
   RESET & BASE
   ========================================== */

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

:root {
    --bg-primary: #060610;
    --bg-navy: #0a0e1a;
    --accent-blue: #3b82f6;
    --accent-blue-bright: #60a5fa;
    --accent-blue-pale: #93c5fd;
    --accent-glow: rgba(59, 130, 246, 0.4);
    --text-primary: #f0f2f5;
    --text-secondary: rgba(255, 255, 255, 0.6);
    --glass-bg: rgba(255, 255, 255, 0.035);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-border-lit: rgba(96, 165, 250, 0.25);

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    --transition-smooth: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ==========================================
   ENVIRONMENTAL LIGHTING SYSTEM
   Three-layer parallax light with blend modes
   ========================================== */

.env-light {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    opacity: 0;
    transition: opacity 1.2s ease;
}

.env-light.active { opacity: 1; }

/* Layer 1 — Large ultra-soft ambient halo */
.env-light__halo {
    position: fixed;
    width: 1100px;
    height: 1100px;
    border-radius: 50%;
    background: radial-gradient(
        circle,
        rgba(59, 130, 246, 0.07) 0%,
        rgba(59, 130, 246, 0.03) 40%,
        transparent 68%
    );
    filter: blur(80px);
    mix-blend-mode: screen;
    transform: translate(-50%, -50%);
    will-change: transform;
}

/* Layer 2 — Medium soft glow */
.env-light__glow {
    position: fixed;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: radial-gradient(
        circle,
        rgba(96, 165, 250, 0.14) 0%,
        rgba(59, 130, 246, 0.07) 35%,
        transparent 65%
    );
    filter: blur(45px);
    mix-blend-mode: screen;
    transform: translate(-50%, -50%);
    will-change: transform;
}

/* Layer 3 — Small bright core */
.env-light__core {
    position: fixed;
    width: 320px;
    height: 320px;
    border-radius: 50%;
    background: radial-gradient(
        circle,
        rgba(147, 197, 253, 0.28) 0%,
        rgba(96, 165, 250, 0.15) 30%,
        rgba(59, 130, 246, 0.06) 55%,
        transparent 70%
    );
    filter: blur(20px);
    mix-blend-mode: screen;
    transform: translate(-50%, -50%);
    will-change: transform;
}

/* ==========================================
   ATMOSPHERE
   ========================================== */

.atmosphere {
    position: fixed;
    inset: 0;
    z-index: 0;
    overflow: hidden;
    transition: filter 1s ease;
}

.atmosphere__gradient {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 130%;
    height: 130%;
    transform: translate(-50%, -50%);
    background: radial-gradient(
        ellipse at 50% 50%,
        rgba(59, 130, 246, 0.12) 0%,
        rgba(30, 64, 175, 0.06) 25%,
        transparent 65%
    );
    will-change: transform, background;
    animation: atmospherePulse 10s ease-in-out infinite;
}

.atmosphere__ambient {
    position: absolute;
    border-radius: 50%;
    filter: blur(70px);
    opacity: 0.25;
    will-change: transform, opacity;
}

.atmosphere__ambient--1 {
    width: 480px; height: 480px;
    top: 8%; left: 15%;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.25) 0%, transparent 70%);
    animation: drift1 18s ease-in-out infinite;
}

.atmosphere__ambient--2 {
    width: 380px; height: 380px;
    bottom: 12%; right: 12%;
    background: radial-gradient(circle, rgba(96, 165, 250, 0.2) 0%, transparent 70%);
    animation: drift2 22s ease-in-out infinite;
}

.atmosphere__ambient--3 {
    width: 320px; height: 320px;
    top: 55%; left: 55%;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.15) 0%, transparent 70%);
    animation: drift3 26s ease-in-out infinite;
}

/* Three.js particle field */
#particleField {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
}

/* Film grain overlay */
.atmosphere__grain {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    opacity: 0.03;
    mix-blend-mode: overlay;
}

/* ==========================================
   MAIN CONTAINER
   ========================================== */

.container {
    position: relative;
    z-index: 2;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
    gap: var(--spacing-2xl);
}

/* ==========================================
   HERO
   ========================================== */

.hero-section {
    text-align: center;
    opacity: 0;
    animation: fadeInUp 1.2s cubic-bezier(0.4, 0, 0.2, 1) forwards 0.4s;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.title-line {
    font-size: clamp(1.5rem, 4vw, 2.5rem);
    font-weight: 300;
    color: var(--text-secondary);
    letter-spacing: 0.05em;
}

.title-brand {
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 700;
    background: linear-gradient(135deg, #ffffff 0%, var(--accent-blue-bright) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.02em;
    position: relative;
}

.title-brand::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent-blue), transparent);
    opacity: 0.5;
}

.hero-subtitle {
    font-size: clamp(1.125rem, 2.5vw, 1.5rem);
    font-weight: 400;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
    opacity: 0;
    animation: fadeInUp 1.2s cubic-bezier(0.4, 0, 0.2, 1) forwards 0.7s;
}

/* ==========================================
   FEATURE CARDS — Proximity-reactive glass
   ========================================== */

.cards-section {
    width: 100%;
    max-width: 1200px;
    opacity: 0;
    animation: fadeInUp 1.2s cubic-bezier(0.4, 0, 0.2, 1) forwards 1s;
}

.cards-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    padding: var(--spacing-md);
}

.feature-card {
    position: relative;
    display: block;
    text-decoration: none;
    color: inherit;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: var(--spacing-xl);
    overflow: hidden;
    cursor: pointer;
    transform-origin: center;
    transition:
        transform 0.5s cubic-bezier(0.4, 0, 0.2, 1),
        border-color 0.8s ease,
        box-shadow 0.8s ease,
        background 0.8s ease;
    animation: floatCard 6s ease-in-out infinite;
    /* JS writes --proximity (0-1) and --light-x / --light-y for reflection */
    --proximity: 0;
    --light-x: 50%;
    --light-y: 50%;
}

.feature-card:nth-child(1) { animation-delay: 0s; }
.feature-card:nth-child(2) { animation-delay: 2s; }
.feature-card:nth-child(3) { animation-delay: 4s; }

/* Animated gradient border — intensity driven by --proximity */
.feature-card::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 24px;
    padding: 1px;
    background: linear-gradient(
        135deg,
        rgba(96, 165, 250, 0.5) 0%,
        rgba(59, 130, 246, 0.25) 50%,
        transparent 100%
    );
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: calc(var(--proximity) * 0.8);
    transition: opacity 0.6s ease;
    pointer-events: none;
}

/* Light reflection that sweeps across card surface */
.feature-card::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 24px;
    background: radial-gradient(
        ellipse 300px 300px at var(--light-x) var(--light-y),
        rgba(147, 197, 253, 0.12) 0%,
        rgba(96, 165, 250, 0.06) 40%,
        transparent 70%
    );
    opacity: var(--proximity);
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.card-glow {
    position: absolute;
    inset: -2px;
    background: radial-gradient(circle at center, var(--accent-glow) 0%, transparent 70%);
    opacity: 0;
    border-radius: 24px;
    z-index: -1;
    filter: blur(20px);
    transition: opacity 0.8s ease;
}

/* Hover adds on top of proximity effects */
.feature-card:hover {
    border-color: var(--glass-border-lit);
    box-shadow:
        0 25px 70px rgba(0, 0, 0, 0.5),
        0 0 50px rgba(59, 130, 246, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.06);
}

.feature-card:hover .card-glow { opacity: 0.6; }

.feature-card:active {
    transform: translateY(-4px) scale(0.995);
    transition-duration: 0.15s;
}

.card-content {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: var(--spacing-md);
}

.card-icon {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(59, 130, 246, 0.08);
    border-radius: 20px;
    color: var(--accent-blue-bright);
    transition: all var(--transition-smooth);
}

.feature-card:hover .card-icon {
    background: rgba(59, 130, 246, 0.16);
    transform: scale(1.08);
    box-shadow: 0 8px 24px rgba(59, 130, 246, 0.25);
}

.card-title {
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    margin: 0;
    transition: color var(--transition-smooth);
}

.feature-card:hover .card-title { color: var(--accent-blue-bright); }

.card-description {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
}

.card-arrow {
    margin-top: var(--spacing-sm);
    color: var(--accent-blue);
    opacity: 0;
    transform: translateX(-10px);
    transition: all var(--transition-smooth);
}

.feature-card:hover .card-arrow {
    opacity: 1;
    transform: translateX(0);
}

/* ==========================================
   KEYFRAMES
   ========================================== */

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes atmospherePulse {
    0%, 100% { opacity: 0.5; transform: translate(-50%, -50%) scale(1); }
    50%      { opacity: 0.65; transform: translate(-50%, -50%) scale(1.04); }
}

@keyframes drift1 {
    0%, 100% { transform: translate(0, 0); opacity: 0.25; }
    33%      { transform: translate(25px, -30px); opacity: 0.35; }
    66%      { transform: translate(-18px, 18px); opacity: 0.28; }
}

@keyframes drift2 {
    0%, 100% { transform: translate(0, 0); opacity: 0.2; }
    33%      { transform: translate(-35px, 25px); opacity: 0.3; }
    66%      { transform: translate(20px, -20px); opacity: 0.25; }
}

@keyframes drift3 {
    0%, 100% { transform: translate(0, 0); opacity: 0.18; }
    33%      { transform: translate(18px, 35px); opacity: 0.28; }
    66%      { transform: translate(-25px, -15px); opacity: 0.22; }
}

@keyframes floatCard {
    0%, 100% { transform: translateY(0); }
    50%      { transform: translateY(-8px); }
}

/* ==========================================
   RESPONSIVE
   ========================================== */

@media (max-width: 1024px) {
    .cards-container {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: var(--spacing-md);
    }
    .container { gap: var(--spacing-xl); }
}

@media (max-width: 768px) {
    :root { --spacing-xl: 2rem; --spacing-2xl: 2.5rem; }

    .cards-container { grid-template-columns: 1fr; padding: var(--spacing-sm); }
    .feature-card { padding: var(--spacing-lg); }

    .env-light { display: none; }

    .atmosphere__ambient--1,
    .atmosphere__ambient--2,
    .atmosphere__ambient--3 { width: 260px; height: 260px; }

    #particleField { opacity: 0.35; }
    .atmosphere__grain { opacity: 0.02; }
}

@media (max-width: 480px) {
    .container { padding: var(--spacing-md); gap: var(--spacing-lg); }
    .hero-title { gap: 0.25rem; }
    .title-brand::after { bottom: -5px; width: 80%; }
    .feature-card { padding: var(--spacing-md); }
    .card-icon { width: 64px; height: 64px; }
    .card-icon svg { width: 36px; height: 36px; }
    .card-title { font-size: 1.5rem; }
    .card-description { font-size: 0.9375rem; }
}

/* ==========================================
   ACCESSIBILITY & PERFORMANCE
   ========================================== */

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    .env-light, #particleField, .atmosphere__grain { display: none; }
}

.feature-card:focus { outline: 2px solid var(--accent-blue); outline-offset: 4px; }
.feature-card:focus:not(:focus-visible) { outline: none; }

.env-light__halo, .env-light__glow, .env-light__core,
.atmosphere__ambient { backface-visibility: hidden; }