/* 
 * index.css
 * Core Design System & Styling Layer for the Studio Portfolio
 * Designed with premium minimalist details, fluid typography, and seamless theme support.
 */

@import url('https://fonts.googleapis.com/css2?family=DM+Sans:ital,opsz,wght@0,9..40,100..1000;1,9..40,100..1000&display=swap');

/* --- DESIGN SYSTEM & CSS VARIABLES --- */
:root {
  /* Colors - Light Theme (Default) */
  --bg: #ffffff;
  --fg: #111111;
  --muted: #707070;
  --faint: #eaeaea;
  --border: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(0, 0, 0, 0.2);
  --card-bg: rgba(255, 255, 255, 0.6);
  --card-hover-bg: rgba(255, 255, 255, 0.9);
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(0, 0, 0, 0.06);
  --input-bg: #fbfbfb;
  --btn-primary-bg: #111111;
  --btn-primary-fg: #ffffff;
  --btn-ghost-border: rgba(0, 0, 0, 0.15);
  --btn-ghost-hover: rgba(0, 0, 0, 0.03);
  --shadow: 0 4px 30px rgba(0, 0, 0, 0.02);
  --shadow-hover: 0 10px 40px rgba(0, 0, 0, 0.05);
  
  /* Fonts */
  --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  
  /* Structural Spacing */
  --header-height: 80px;
  --container-width: 1100px;
  
  /* Timing Curves */
  --ease-premium: cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.5s var(--ease-premium);
  --transition-fast: 0.25s var(--ease-premium);
}

/* Colors - Dark Theme Override */
[data-theme="dark"] {
  --bg: #0b0b0b;
  --fg: #f5f5f7;
  --muted: #86868b;
  --faint: #222224;
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.2);
  --card-bg: rgba(20, 20, 22, 0.5);
  --card-hover-bg: rgba(28, 28, 30, 0.8);
  --glass-bg: rgba(11, 11, 11, 0.8);
  --glass-border: rgba(255, 255, 255, 0.05);
  --input-bg: #141416;
  --btn-primary-bg: #f5f5f7;
  --btn-primary-fg: #0b0b0b;
  --btn-ghost-border: rgba(255, 255, 255, 0.25);
  --btn-ghost-hover: rgba(255, 255, 255, 0.03);
  --shadow: 0 4px 30px rgba(0, 0, 0, 0.2);
  --shadow-hover: 0 10px 40px rgba(0, 0, 0, 0.4);
}

/* Fallback auto dark mode if manual preference is not set */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0b0b0b;
    --fg: #f5f5f7;
    --muted: #86868b;
    --faint: #222224;
    --border: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(255, 255, 255, 0.2);
    --card-bg: rgba(20, 20, 22, 0.5);
    --card-hover-bg: rgba(28, 28, 30, 0.8);
    --glass-bg: rgba(11, 11, 11, 0.8);
    --glass-border: rgba(255, 255, 255, 0.05);
    --input-bg: #141416;
    --btn-primary-bg: #f5f5f7;
    --btn-primary-fg: #0b0b0b;
    --btn-ghost-border: rgba(255, 255, 255, 0.25);
    --btn-ghost-hover: rgba(255, 255, 255, 0.03);
    --shadow: 0 4px 30px rgba(0, 0, 0, 0.2);
    --shadow-hover: 0 10px 40px rgba(0, 0, 0, 0.4);
  }
}

/* --- RESET & GLOBAL STYLES --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color var(--transition-smooth), color var(--transition-smooth);
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg);
}
::-webkit-scrollbar-thumb {
  background: var(--faint);
  border-radius: 10px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--muted);
}

/* Typography Selection */
::selection {
  background: var(--fg);
  color: var(--bg);
}

/* Layout Container */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 2rem;
  width: 100%;
}

/* --- FIXED NAVIGATION BAR --- */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2.5rem;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background-color var(--transition-smooth), border-color var(--transition-smooth), transform var(--transition-smooth);
}

.logo {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 15px;
  color: var(--fg);
  text-decoration: none;
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-links {
  display: flex;
  gap: 2.5rem;
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  position: relative;
  padding: 6px 0;
  transition: color var(--transition-fast);
}

.nav-links a:hover {
  color: var(--fg);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 100%;
  height: 1px;
  background: var(--fg);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.4s var(--ease-premium);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-links a.active {
  color: var(--fg);
}

/* --- HERO SECTION --- */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 8rem 2rem 4rem;
  position: relative;
}

.divider-line {
  width: 1px;
  height: 64px;
  background: var(--faint);
  margin: 0 auto 2.5rem;
  transition: background-color var(--transition-smooth);
}

.eyebrow {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 1.75rem;
  transition: color var(--transition-smooth);
}

h1 {
  font-family: var(--font-sans);
  font-size: clamp(3.2rem, 9.5vw, 6.8rem);
  font-weight: 500;
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--fg);
  margin-bottom: 1.5rem;
  transition: color var(--transition-smooth);
}

h1 .dim {
  color: var(--muted);
  transition: color var(--transition-smooth);
}

.subtitle {
  font-size: 1.15rem;
  color: var(--muted);
  line-height: 1.75;
  max-width: 460px;
  margin: 0 auto 2.5rem;
  transition: color var(--transition-smooth);
}

.cta-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

/* --- BUTTONS --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: 8px;
  font-family: var(--font-sans);
  font-size: 14.5px;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), opacity var(--transition-fast);
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-fg);
}

.btn-primary:hover {
  transform: translateY(-2px);
  opacity: 0.9;
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-ghost {
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--btn-ghost-border);
}

.btn-ghost:hover {
  color: var(--fg);
  border-color: var(--fg);
  background: var(--btn-ghost-hover);
  transform: translateY(-2px);
}

.btn-ghost:active {
  transform: translateY(0);
}

/* --- SECTIONS MAIN STRUCTURE --- */
section.page-section {
  padding: 8rem 0;
  border-top: 1px solid var(--border);
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition-smooth);
}

.section-header {
  margin-bottom: 4rem;
  max-width: 600px;
}

.section-eyebrow {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 500;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--fg);
  margin-bottom: 1rem;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--muted);
  max-width: 500px;
}

/* --- ABOUT SECTION --- */
.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.5rem;
  margin-top: 2rem;
}

.about-card {
  padding: 2.5rem;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  transition: background-color var(--transition-smooth), border-color var(--transition-smooth), transform var(--transition-smooth), box-shadow var(--transition-smooth);
}

.about-card:hover {
  transform: translateY(-6px);
  background: var(--card-hover-bg);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-hover);
}

.about-num {
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  margin-bottom: 2rem;
  font-family: monospace;
}

.about-card h3 {
  font-size: 1.4rem;
  font-weight: 500;
  color: var(--fg);
  margin-bottom: 1rem;
  letter-spacing: -0.01em;
}

.about-card p {
  font-size: 0.95rem;
  color: var(--muted);
  line-height: 1.6;
}

/* --- WORK SECTION --- */
.work-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 3rem;
  margin-top: 1rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: var(--fg);
  group-hover: pointer;
}

.project-image-wrapper {
  position: relative;
  aspect-ratio: 16 / 10;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color var(--transition-smooth), transform var(--transition-smooth), box-shadow var(--transition-smooth);
}

.project-card:hover .project-image-wrapper {
  transform: translateY(-6px);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-hover);
}

/* Minimalist Decorative Visuals instead of placeholders */
.project-visual {
  width: 100%;
  height: 100%;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(circle at top left, var(--faint), transparent);
  transition: background var(--transition-smooth);
}

.project-card:hover .project-visual {
  background: radial-gradient(circle at top left, var(--border), transparent);
}

/* Visual Mockups */
.visual-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  border: 1px solid var(--border-hover);
  position: relative;
  transition: transform 0.6s var(--ease-premium);
}
.project-card:hover .visual-circle {
  transform: scale(1.15) rotate(45deg);
}

.visual-rect {
  width: 100px;
  height: 60px;
  border: 1px solid var(--border-hover);
  border-radius: 8px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.6s var(--ease-premium);
}
.project-card:hover .visual-rect {
  transform: scale(1.1) translateY(-4px);
}
.visual-rect::after {
  content: '';
  width: 40px;
  height: 1px;
  background: var(--fg);
}

.visual-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  transition: transform 0.6s var(--ease-premium);
}
.project-card:hover .visual-grid {
  transform: scale(1.08) rotate(-5deg);
}
.visual-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--muted);
  opacity: 0.3;
}
.visual-dot.active {
  background: var(--fg);
  opacity: 1;
}

.visual-wave {
  display: flex;
  align-items: center;
  gap: 4px;
  height: 40px;
}
.visual-bar {
  width: 3px;
  height: 15px;
  background: var(--muted);
  border-radius: 2px;
  transition: height 0.3s ease, background-color var(--transition-smooth);
}
.visual-bar:nth-child(even) { height: 30px; }
.visual-bar:nth-child(3) { height: 20px; }
.project-card:hover .visual-bar {
  background: var(--fg);
}
.project-card:hover .visual-bar:nth-child(1) { height: 35px; }
.project-card:hover .visual-bar:nth-child(2) { height: 18px; }
.project-card:hover .visual-bar:nth-child(3) { height: 28px; }
.project-card:hover .visual-bar:nth-child(4) { height: 12px; }

.project-details {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.project-info h3 {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--fg);
  margin-bottom: 0.25rem;
  letter-spacing: -0.01em;
}

.project-category {
  font-size: 13px;
  color: var(--muted);
}

.project-arrow {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color var(--transition-fast), background-color var(--transition-fast), transform var(--transition-fast);
}

.project-arrow svg {
  width: 14px;
  height: 14px;
  fill: none;
  stroke: var(--fg);
  stroke-width: 1.5;
  transition: transform var(--transition-fast);
}

.project-card:hover .project-arrow {
  border-color: var(--fg);
  background: var(--fg);
}

.project-card:hover .project-arrow svg {
  stroke: var(--bg);
  transform: translate(1px, -1px);
}

/* --- CONTACT SECTION --- */
.contact-container {
  display: grid;
  grid-template-columns: 4fr 5fr;
  gap: 5rem;
  align-items: start;
}

.contact-meta {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.contact-method {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.contact-method-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.contact-method-value {
  font-size: 1.15rem;
  color: var(--fg);
  text-decoration: none;
  font-weight: 400;
  transition: color var(--transition-fast);
  display: inline-block;
  align-self: flex-start;
}

.contact-method-value:hover {
  color: var(--muted);
}

.contact-form-wrapper {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 3rem;
  transition: background-color var(--transition-smooth), border-color var(--transition-smooth);
}

.form-group {
  position: relative;
  margin-bottom: 2.5rem;
}

.form-input {
  width: 100%;
  padding: 12px 0;
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--border);
  font-family: var(--font-sans);
  font-size: 15px;
  color: var(--fg);
  outline: none;
  transition: border-color var(--transition-fast);
}

.form-label {
  position: absolute;
  left: 0;
  top: 12px;
  font-size: 14px;
  color: var(--muted);
  pointer-events: none;
  transition: transform 0.3s var(--ease-premium), color 0.3s var(--ease-premium), font-size 0.3s var(--ease-premium);
  transform-origin: left top;
}

/* Floating Label Behavior */
.form-input:focus ~ .form-label,
.form-input:not(:placeholder-shown) ~ .form-label {
  transform: translateY(-24px) scale(0.85);
  color: var(--fg);
}

.form-input:focus {
  border-bottom-color: var(--fg);
}

/* Focus Line Indicator */
.form-focus-line {
  position: absolute;
  bottom: 0; left: 0;
  width: 100%;
  height: 1.5px;
  background: var(--fg);
  transform: scaleX(0);
  transition: transform 0.4s var(--ease-premium);
}
.form-input:focus ~ .form-focus-line {
  transform: scaleX(1);
}

textarea.form-input {
  min-height: 100px;
  resize: none;
}

/* Submit Status */
.submit-status {
  margin-top: 1rem;
  font-size: 14px;
  font-weight: 500;
  opacity: 0;
  transform: translateY(5px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}
.submit-status.success {
  color: #10b981;
  opacity: 1;
  transform: translateY(0);
}
.submit-status.error {
  color: #ef4444;
  opacity: 1;
  transform: translateY(0);
}

/* --- FOOTER --- */
footer {
  text-align: center;
  padding: 4rem 2rem;
  font-size: 12.5px;
  color: var(--muted);
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  transition: border-color var(--transition-smooth);
}

.footer-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.footer-links a {
  color: var(--muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

/* --- FLOATING THEME SWITCHER --- */
.theme-toggle-btn {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 9999;
  box-shadow: var(--shadow);
  transition: background-color var(--transition-smooth), border-color var(--transition-smooth), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.theme-toggle-btn:hover {
  transform: scale(1.08) translateY(-2px);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-hover);
}

.theme-toggle-btn:active {
  transform: scale(0.98);
}

.theme-toggle-btn svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: var(--fg);
  stroke-width: 2;
  transition: stroke var(--transition-smooth), transform 0.6s var(--ease-premium);
}

/* Custom Multi-Theme Cycling Icons (System -> Light -> Dark) */
.theme-toggle-btn .system-icon,
.theme-toggle-btn .sun-icon,
.theme-toggle-btn .moon-icon {
  display: none;
}

/* 1. System Mode Icons */
.theme-toggle-btn[data-mode="system"] .system-icon {
  display: block;
}

/* 2. Forced Light Mode Icons */
.theme-toggle-btn[data-mode="light"] .sun-icon {
  display: block;
}

/* 3. Forced Dark Mode Icons */
.theme-toggle-btn[data-mode="dark"] .moon-icon {
  display: block;
}

/* Dynamic Hover rotations for premium feel */
.theme-toggle-btn:hover[data-mode="light"] .sun-icon {
  transform: rotate(45deg);
}
.theme-toggle-btn:hover[data-mode="system"] .system-icon {
  transform: rotate(-15deg);
}
.theme-toggle-btn:hover[data-mode="dark"] .moon-icon {
  transform: scale(1.1);
}

/* --- FADE-IN & SCROLL-REVEAL ANIMATIONS --- */
@keyframes fadeUpIn {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Page Entry Delays for Hero Section */
.hero > * {
  animation: fadeUpIn 1s var(--ease-premium) both;
}
.hero > *:nth-child(1) { animation-delay: 0.05s; } /* divider */
.hero > *:nth-child(2) { animation-delay: 0.15s; } /* eyebrow */
.hero > *:nth-child(3) { animation-delay: 0.25s; } /* h1 */
.hero > *:nth-child(4) { animation-delay: 0.35s; } /* subtitle */
.hero > *:nth-child(5) { animation-delay: 0.45s; } /* cta-row */

/* Scroll Reveal Classes */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 1.2s var(--ease-premium), transform 1.2s var(--ease-premium);
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* Cascade effect for child elements inside revealed sections */
.cascade-parent .cascade-child {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.8s var(--ease-premium), transform 0.8s var(--ease-premium);
}

.cascade-parent.revealed .cascade-child {
  opacity: 1;
  transform: translateY(0);
}

.cascade-parent.revealed .cascade-child:nth-child(1) { transition-delay: 0.1s; }
.cascade-parent.revealed .cascade-child:nth-child(2) { transition-delay: 0.2s; }
.cascade-parent.revealed .cascade-child:nth-child(3) { transition-delay: 0.3s; }
.cascade-parent.revealed .cascade-child:nth-child(4) { transition-delay: 0.4s; }

/* --- RESPONSIVE LAYOUTS --- */
@media (max-width: 968px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .work-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  
  .contact-container {
    grid-template-columns: 1fr;
    gap: 3.5rem;
  }
  
  .contact-meta {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 3rem;
  }
}

@media (max-width: 600px) {
  nav {
    padding: 0 1.5rem;
  }
  
  .nav-links {
    gap: 1.5rem;
  }
  
  .nav-links a {
    font-size: 13px;
  }
  
  .hero {
    padding: 6rem 1rem 3rem;
  }
  
  h1 {
    font-size: 3.2rem;
  }
  
  .cta-row {
    flex-direction: column;
    width: 100%;
    max-width: 280px;
    margin: 0 auto;
  }
  
  .btn {
    width: 100%;
  }
  
  .contact-meta {
    flex-direction: column;
    gap: 1.5rem;
  }
  
  .contact-form-wrapper {
    padding: 2rem 1.5rem;
  }
  
  .theme-toggle-btn {
    bottom: 1.5rem;
    right: 1.5rem;
  }
}