/* 
 * KKTech - Professional High-Utility Theme
 * Inspired by Vercel, Linear, and ChatGPT
 * Aesthetic: Monochromatic, Precision, Technical
 */

@import url('https://fonts.googleapis.com/css2?family=Inter:ital,opsz,wght@0,14..32,100..900;1,14..32,100..900&family=Outfit:wght@100..900&display=swap');

:root {
    /* Grayscale Palette (Vercel/Linear standard) */
    --white: #ffffff;
    --gray-50: #fafafa;
    --gray-100: #f5f5f5;
    --gray-200: #eaeaea;
    --gray-300: #999999;
    --gray-400: #888888;
    --gray-500: #666666;
    --gray-600: #444444;
    --gray-700: #333333;
    --gray-800: #111111;
    --black: #000000;
    --radius-main: 10px;

    /* Semantic Accents (Minimalist) */
    --primary: #000000;
    --primary-light: #333333;
    --accent: #0070f3; /* Vercel Blue - used very sparingly for focus/links */
    
    /* System Tokens */
    --bg-app: var(--white);
    --text-main: var(--black);
    --text-secondary: var(--gray-500);
    --border-main: var(--gray-200);
    --border-hover: var(--gray-800);
}

[data-theme="dark"] {
    --white: #000000;
    --gray-50: #111111;
    --gray-100: #1a1a1a;
    --gray-200: #333333;
    --gray-300: #444444;
    --gray-400: #666666;
    --gray-500: #888888;
    --gray-600: #999999;
    --gray-700: #eaeaea;
    --gray-800: #f5f5f5;
    --black: #ffffff;

    --bg-app: #000000;
    --text-main: #ffffff;
    --text-secondary: var(--gray-500);
    --border-main: #333333;
    --border-hover: #ffffff;
    
    --primary: #ffffff;
    --primary-light: #eaeaea;
}

:root {
    /* Spacing Scale (8pt grid) */
    --s-1: 4px;
    --s-2: 8px;
    --s-3: 12px;
    --s-4: 16px;
    --s-5: 20px;
    --s-6: 24px;
    --s-8: 32px;
    --s-10: 40px;
    --s-12: 48px;
    --s-16: 64px;
    --s-20: 80px;

    /* Typo */
    --font-sans: 'Inter', -apple-system, sans-serif;
    --font-display: 'Outfit', sans-serif;

    /* Effects */
    --shadow-minimal: 0 0 0 1px rgba(0, 0, 0, 0.05), 0 2px 4px rgba(0, 0, 0, 0.02);
    --shadow-elevated: 0 0 0 1px rgba(0, 0, 0, 0.1), 0 8px 16px rgba(0, 0, 0, 0.08);
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
}

/* Custom Scrollbar Global */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--gray-50);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-200);
    border-radius: var(--radius-main);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-300);
}

body {
    font-family: var(--font-sans);
    color: var(--text-main);
    background-color: var(--bg-app);
    line-height: 1.5;
    font-feature-settings: "cv02", "cv03", "cv04", "cv11";
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--s-6);
}

/* Typography Hierarchy */
h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 600;
    letter-spacing: -0.025em;
    color: var(--black);
}

h1 { font-size: clamp(3rem, 8vw, 5rem); line-height: 0.95; }
h2 { font-size: clamp(2rem, 5vw, 2.5rem); line-height: 1.1; }
h3 { font-size: 1.25rem; font-weight: 500; }

p {
    color: var(--text-secondary);
    font-size: 1.0625rem;
    max-width: 65ch;
}

.meta-label {
    font-size: 0.625rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--gray-500);
    margin-bottom: var(--s-3);
    display: block;
}

/* UI Elements */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--border-main);
    height: 64px;
    display: flex;
    align-items: center;
}

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

.logo {
    text-decoration: none;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--black);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    width: 24px;
    height: 24px;
    background: var(--black);
    border-radius: var(--radius-main);
}

.nav-links {
    display: flex;
    gap: var(--s-8);
    list-style: none;
}

.nav-link {
    text-decoration: none;
    font-size: 0.875rem;
    color: var(--gray-500);
    transition: color 0.2s;
}

.nav-link:hover { color: var(--black); }

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--s-2) var(--s-4);
    border-radius: var(--radius-main);
    font-size: 0.875rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
    border: 1px solid transparent;
}

.btn-black {
    background: var(--black);
    color: var(--white);
    border: 1px solid var(--black);
}

.btn-black:hover {
    background: var(--gray-800);
    box-shadow: 0 4px 14px 0 rgba(0,0,0,0.1);
}

.btn-ghost {
    background: transparent;
    color: var(--gray-500);
}

.btn-ghost:hover {
    background: var(--gray-100);
    color: var(--black);
}

/* Sections */
.section {
    padding: var(--s-20) 0;
}

.hero {
    text-align: center;
    padding: var(--s-20) 0 var(--s-32);
    min-height: 80vh;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--border-main);
}

.hero p {
    margin: var(--s-6) auto var(--s-10);
}

/* Bento-inspired Precision Grid */
.bento {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 1px;
    background: var(--border-main);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-main);
    overflow: hidden;
}

.bento-card {
    background: var(--white);
    padding: var(--s-8);
    transition: background 0.2s;
    display: flex;
    flex-direction: column;
}

.bento-card:hover {
    background: var(--gray-50);
}

.span-4 { grid-column: span 4; }
.span-6 { grid-column: span 6; }
.span-8 { grid-column: span 8; }
.span-12 { grid-column: span 12; }

.bento-card h3 {
    margin-bottom: var(--s-2);
}

.icon-box {
    width: 32px;
    height: 32px;
    border: 1px solid var(--border-main);
    border-radius: var(--radius-main);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--s-6);
    background: var(--white);
}

/* Footer (Gmail/Chat style) */
.footer {
    padding: var(--s-16) 0 var(--s-8);
    border-top: 1px solid var(--border-main);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--s-12);
}

.footer-col h4 {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--s-6);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--s-3);
}

.footer-links a {
    text-decoration: none;
    font-size: 0.8125rem;
    color: var(--gray-500);
}

.footer-links a:hover { color: var(--black); }

/* Responsive */
@media (max-width: 900px) {
    .span-4, .span-6, .span-8 { grid-column: span 6; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
    .span-4, .span-6, .span-8, .span-12 { grid-column: span 12; }
    .footer-grid { grid-template-columns: 1fr; }
    .hero h1 { font-size: 2.5rem; }
    .nav-links { display: none; }
}

/* Micro-animations */
.fade-in {
    opacity: 0;
    animation: fadeIn 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}