/* DESIGN Arc™ - Apple-Grade Premium Architecture CSS */

:root {
    --color-bg: #0B1B33; /* Deep Royal Blue */
    --color-accent: #D4AF37; /* Matte Gold */
    --color-text: #F5F5F7; /* Crisp Off-White (Apple standard) */
    --color-nav-glass: rgba(11, 27, 51, 0.7);
    --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'Playfair Display', serif;
}

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

html {
    scroll-behavior: smooth;
    background-color: var(--color-bg);
}

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-heading);
    overflow-x: hidden;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Custom Cursor trailing overlay */
#cursor-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 10000;
}
.cursor-dot {
    position: absolute;
    width: 4px;
    height: 4px;
    background-color: var(--color-accent);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    box-shadow: 0 0 10px rgba(212, 175, 55, 0.8);
    opacity: 0.8;
}

/* Hero Intro Canvas Animation */
#hero-intro {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100vh;
    background-color: var(--color-bg);
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: opacity 1.5s cubic-bezier(0.16, 1, 0.3, 1), visibility 1.5s;
}
canvas {
    width: 100%; height: 100%;
}
body.loading #main-content {
    opacity: 0;
}

#main-content {
    transition: opacity 2s ease-in-out;
}

/* Typography */
h1, h2, h3 {
    font-weight: 800;
    letter-spacing: -0.02em;
}
h2 {
    font-size: clamp(2rem, 5vw, 4rem);
    margin-bottom: 2rem;
}
.serif-desc {
    font-family: var(--font-serif);
    font-style: italic;
    color: #A1A1A6;
    font-size: 1.5rem;
    line-height: 1.8;
}

/* Glassmorphism Header */
.glass-nav {
    position: fixed;
    top: 0; width: 100%;
    background: var(--color-nav-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 100;
    padding: 1.5rem 0;
    transition: transform 0.3s;
}
.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}
.glass-nav nav a {
    color: var(--color-text);
    text-decoration: none;
    margin-left: 3rem;
    font-weight: 400;
    font-size: 0.95rem;
    transition: color 0.3s ease;
}
.glass-nav nav a:hover {
    color: var(--color-accent);
}

/* Sections & Layout */
.section-padding { padding: 8rem 2rem; }
.container {
    max-width: 1400px;
    margin: 0 auto;
}
.layout-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 6rem;
    align-items: center;
}

/* Hero Image Section (Under Intro) */
.hero-bg {
    height: 100vh;
    background: linear-gradient(rgba(11, 27, 51, 0.2), rgba(11, 27, 51, 1)), url('assets/hero_bg.png') center/cover no-repeat;
    display: flex;
    align-items: flex-end;
    padding: 6rem 2rem;
}
.hero-content {
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}
.hero-content h1 {
    font-size: clamp(3rem, 8vw, 7rem);
    line-height: 1.05;
    margin-bottom: 1rem;
    color: #fff;
}

/* Nathan Gao Style Large Project Cards */
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 6rem;
    margin-top: 4rem;
}
.project-card {
    position: relative;
    border-radius: 20px;
    overflow: hidden;
    height: 75vh;
    mask-image: -webkit-radial-gradient(white, black);
    /* HW Acceleration */
    transform: translateZ(0); 
}
.project-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 1.5s cubic-bezier(0.16, 1, 0.3, 1);
}
.project-card:hover img {
    transform: scale(1.05); /* Hardware accelerated */
}
.card-overlay {
    position: absolute;
    bottom: 0; left: 0;
    width: 100%;
    padding: 4rem;
    background: linear-gradient(to top, rgba(11, 27, 51, 0.9) 0%, transparent 100%);
    pointer-events: none;
}
.card-overlay h3 {
    font-size: clamp(2rem, 4vw, 3.5rem);
    color: var(--color-accent);
    margin-bottom: 0.5rem;
}

/* Premium Form */
.premium-form {
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
}
.premium-form input, .premium-form textarea {
    background: transparent;
    border: none;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    color: var(--color-text);
    padding: 1rem 0;
    font-size: 1.1rem;
    font-family: var(--font-heading);
    transition: border-color 0.3s;
}
.premium-form input:focus, .premium-form textarea:focus {
    outline: none;
    border-bottom: 1px solid var(--color-accent);
}
.premium-form textarea {
    min-height: 120px;
    resize: none;
}
.btn-primary {
    background-color: var(--color-accent);
    color: var(--color-bg);
    border: none;
    padding: 1.2rem 3rem;
    font-weight: 800;
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    cursor: pointer;
    border-radius: 4px;
    transition: transform 0.3s ease, background-color 0.3s ease;
    align-self: flex-start;
}
.btn-primary:hover {
    transform: translateY(-2px);
    background-color: #eed686;
}

/* Semantic Footer */
footer {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 4rem 2rem;
    background-color: var(--color-bg);
}
.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.footer-brand p {
    font-size: 1.5rem;
}
.footer-brand .small-text {
    color: #6e6e73;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    font-weight: 300;
}
.footer-links a {
    color: #A1A1A6;
    text-decoration: none;
    margin-left: 2rem;
    font-size: 0.9rem;
    transition: color 0.3s;
}
.footer-links a:hover {
    color: var(--color-text);
}

/* Scroll Reveal Animations */
.section-reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: all 1.2s cubic-bezier(0.16, 1, 0.3, 1);
}
.section-reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive constraints */
@media (max-width: 1024px) {
    .layout-grid { grid-template-columns: 1fr; gap: 3rem; }
    .footer-content { flex-direction: column; align-items: flex-start; gap: 2rem; }
    .footer-links { margin-left: -2rem; }
    .project-card { height: 50vh; }
}