/* =====================================================================
   Portfolio — shared page styles
   Imports colors_and_type.css for tokens; this file handles theming,
   layout primitives, nav, footer, and common components.
   ===================================================================== */

/* ─── Dark mode base ─────────────────────────────────────────── */
html[data-theme="dark"] {
  --bg: #0B2E33; --bg-elev: #143A40; --bg-warm: #1A3C41;
  --paper: #0B2E33; --paper-2: #143A40;
  --fg-1: #F4F4F0; --fg-2: #B8E3E9; --fg-3: #6B9398;
  --fg-mute: #4F7C82; --fg-invert: #0B2E33;
  --border: #1F4D54; --border-strong: #2A6068;
  --line-100: #1F4D54; --line-200: #2A6068; --line-300: #4F7C82;
}
/* bg-variant overrides set via JS inline style */

/* ─── Light mode overrides ───────────────────────────────────── */
html[data-theme="light"] {
  --bg: #F1F8F9; --bg-elev: #FFFFFF;
  --paper: #F1F8F9; --paper-2: #E8F3F5;
  --fg-1: #0B2E33; --fg-2: #3A5458; --fg-3: #5A7880;
  --fg-mute: #B8D4D8; --fg-invert: #F1F8F9;
  --border: #D4E8EC; --border-strong: #B8D4D8;
  --line-100: #D4E8EC; --line-200: #B8D4D8; --line-300: #4F7C82;
}

/* ─── Grid motif ─────────────────────────────────────────────── */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(to right,  var(--border) 1px, transparent 1px),
    linear-gradient(to bottom, var(--border) 1px, transparent 1px);
  background-size: 80px 80px;
  opacity: 0.6;
}

/* ─── Base ───────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
html, body { background: var(--bg); margin: 0; }
body {
  color: var(--fg-1); font-family: var(--font-sans);
  transition: background var(--dur-3) var(--ease-std), color var(--dur-3) var(--ease-std);
}

/* ─── Layout wrap ────────────────────────────────────────────── */
.wrap { position: relative; z-index: 1; max-width: 1080px; margin: 0 auto; padding: 0 var(--sp-7); }

/* ─── Nav ────────────────────────────────────────────────────── */
/* ─── Skip to content ────────────────────────────────────────── */
.skip-link {
  position: absolute; top: -100%; left: var(--sp-5);
  background: var(--bg-elev); color: var(--accent);
  padding: var(--sp-2) var(--sp-4); border-radius: var(--r-sm);
  font-family: var(--font-mono); font-size: var(--fs-xs);
  letter-spacing: var(--tracking-wide);
  z-index: 10000; text-decoration: none;
  border: 1px solid var(--border);
  transition: top var(--dur-1) var(--ease-std);
}
.skip-link:focus { top: var(--sp-3); outline: 2px solid var(--accent); outline-offset: 2px; }

.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in oklab, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur-2) var(--ease-std), background var(--dur-3) var(--ease-std);
}
.nav[data-scrolled] { border-bottom-color: var(--border); }
.nav-inner {
  max-width: 1080px; margin: 0 auto; padding: var(--sp-4) var(--sp-7);
  display: flex; align-items: center; justify-content: space-between; gap: var(--sp-6);
}
.nav-brand {
  display: inline-flex; align-items: center; gap: var(--sp-2);
  text-decoration: none; font-family: var(--font-mono);
  font-size: var(--fs-2xs); letter-spacing: var(--tracking-caps); text-transform: uppercase;
  color: var(--fg-1); white-space: nowrap;
}
.nav-mark {
  width: 14px; height: 14px; border: 1.5px solid var(--fg-1);
  border-radius: var(--r-xs); position: relative; display: inline-block;
  transition: border-color var(--dur-2) var(--ease-std);
}
.nav-mark::after {
  content: ""; position: absolute; inset: 3px; background: var(--accent);
  border-radius: 1px; transition: background var(--dur-2) var(--ease-std);
}
.nav-links { display: flex; gap: var(--sp-5); font-family: var(--font-mono); font-size: var(--fs-2xs); letter-spacing: var(--tracking-wide); }
.nav-links a { position: relative; color: var(--fg-3); text-decoration: none; transition: color var(--dur-1) var(--ease-std); }
.nav-links a:hover, .nav-links a[aria-current] { color: var(--accent); }
/* Active-page underline tick — unmistakable beyond color alone */
.nav-links a[aria-current]::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -7px;
  height: 1.5px; background: var(--accent); border-radius: 1px;
}

/* ⌘K command-palette hint badge (injected into nav by portfolio.js) */
#cmd-badge {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: var(--font-mono); font-size: var(--fs-3xs);
  letter-spacing: var(--tracking-wide); text-transform: uppercase;
  color: var(--fg-3); background: none; cursor: pointer;
  border: 1px solid var(--border); border-radius: var(--r-xs);
  padding: 4px 8px;
  transition: border-color var(--dur-1) var(--ease-std), color var(--dur-1) var(--ease-std);
}
#cmd-badge:hover { border-color: var(--border-strong); color: var(--fg-2); }
#cmd-badge kbd {
  font-family: var(--font-mono); font-size: inherit; color: var(--fg-2);
  background: none; border: 0; padding: 0;
}
@media (max-width: 680px) { #cmd-badge { display: none; } }

.theme-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; flex-shrink: 0;
  background: transparent; border: none; border-radius: var(--r-sm);
  color: var(--fg-3); cursor: pointer;
  transition: color var(--dur-1) var(--ease-std), background var(--dur-1) var(--ease-std);
}
.theme-toggle:hover {
  color: var(--accent);
  background: color-mix(in oklab, var(--accent) 10%, transparent);
}
.theme-toggle .ico { width: 16px; height: 16px; stroke-width: 1.75; }

/* Show sun in dark mode (click → go light); moon in light mode (click → go dark) */
html[data-theme="dark"]  .theme-icon-sun  { display: block; }
html[data-theme="dark"]  .theme-icon-moon { display: none; }
html[data-theme="light"] .theme-icon-sun  { display: none; }
html[data-theme="light"] .theme-icon-moon { display: block; }

/* ─── Section primitive ──────────────────────────────────────── */
section.block { padding: var(--section-gap) 0; border-top: 1px solid var(--border); }
.section-head { display: flex; align-items: center; justify-content: space-between; gap: var(--sp-4); margin-bottom: var(--sp-7); }
.section-label { font-family: var(--font-mono); font-size: var(--fs-2xs); letter-spacing: var(--tracking-caps); text-transform: uppercase; color: var(--fg-3); transition: all var(--dur-3) var(--ease-std); }
.section-aside { font-family: var(--font-mono); font-size: var(--fs-2xs); color: var(--fg-3); text-decoration: none; }
.section-aside:hover { color: var(--accent); }

/* ─── Row list ───────────────────────────────────────────────── */
.row-list { display: flex; flex-direction: column; }
.row-item {
  display: grid; grid-template-columns: 60px 1fr auto;
  gap: var(--sp-5); padding: var(--row-y) 0;
  border-top: 1px solid var(--border);
  text-decoration: none; color: inherit; align-items: start;
}
.row-item:first-child { border-top: 0; padding-top: 0; }
.row-item:last-child  { padding-bottom: 0; }
.row-key { font-family: var(--font-mono); font-size: var(--fs-2xs); color: var(--fg-3); font-variant-numeric: tabular-nums; padding-top: 5px; }
.row-body { display: flex; flex-direction: column; gap: 5px; }
.row-title {
  font-size: var(--fs-md); font-weight: 500; color: var(--fg-1);
  display: inline-flex; align-items: center; gap: var(--sp-2);
  transition: color var(--dur-1) var(--ease-std);
}
.row-arrow { width: 13px; height: 13px; color: var(--fg-mute); opacity: 0; transition: opacity var(--dur-2) var(--ease-std), transform var(--dur-2) var(--ease-out), color var(--dur-2) var(--ease-std); }
.row-desc { font-size: var(--fs-sm); color: var(--fg-3); line-height: var(--lh-snug); }
.row-tag  { font-family: var(--font-mono); font-size: var(--fs-3xs); color: var(--fg-3); letter-spacing: var(--tracking-wide); text-transform: uppercase; white-space: nowrap; padding-top: 6px; }
.row-item:hover .row-title { color: var(--accent); }
.row-item:hover .row-arrow { opacity: 1; color: var(--accent); transform: translate(2px,-2px); }

/* ─── Buttons ────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: var(--sp-2);
  padding: 10px var(--sp-4); border-radius: var(--r-sm);
  font-size: var(--fs-sm); font-weight: 500; text-decoration: none;
  transition: background var(--dur-2) var(--ease-std), border-color var(--dur-2) var(--ease-std), color var(--dur-2) var(--ease-std), transform var(--dur-1) var(--ease-std);
  cursor: pointer; border: 1px solid transparent;
}
.btn:active { transform: scale(0.98); }
.btn-fill  { background: var(--fg-1); color: var(--bg); border-color: var(--fg-1); }
.btn-fill:hover  { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-ghost { background: transparent; color: var(--fg-1); border-color: var(--border-strong); }
.btn-ghost:hover { border-color: var(--fg-1); color: var(--accent); }
.btn .ico { width: 14px; height: 14px; stroke-width: 1.75; }

/* ─── Footer ─────────────────────────────────────────────────── */
footer.foot {
  padding: var(--sp-9) 0 var(--sp-11);
  border-top: 1px solid var(--border);
  display: flex; justify-content: space-between; align-items: flex-end; flex-wrap: wrap; gap: var(--sp-6);
}
.foot-links { display: flex; flex-direction: column; gap: var(--sp-3); }
.foot-link  {
  display: inline-flex; align-items: center; gap: var(--sp-2);
  font-family: var(--font-mono); font-size: var(--fs-2xs);
  letter-spacing: var(--tracking-wide); text-transform: uppercase;
  color: var(--fg-2); text-decoration: none;
  transition: color var(--dur-1) var(--ease-std);
}
.foot-link:hover { color: var(--accent); }
.foot-link .ico { width: 12px; height: 12px; opacity: .7; transition: transform var(--dur-2) var(--ease-out), opacity var(--dur-2) var(--ease-std); }
.foot-link:hover .ico { transform: translate(2px,-2px); opacity: 1; }
.foot-copy { font-family: var(--font-mono); font-size: var(--fs-3xs); color: var(--fg-3); text-align: right; line-height: var(--lh-snug); letter-spacing: var(--tracking-wide); text-transform: uppercase; }

/* ─── Focus ──────────────────────────────────────────────────── */
:focus-visible { outline: none; box-shadow: var(--focus-ring); border-radius: 3px; }

/* ─── Terminal components ────────────────────────────────────── */
.term-path {
  font-family: var(--font-mono); font-size: var(--fs-xs);
  color: var(--fg-3); letter-spacing: var(--tracking-wide);
  margin-bottom: var(--sp-2);
}
.term-line {
  font-family: var(--font-mono); font-size: var(--fs-sm);
  color: var(--fg-3); margin-bottom: var(--sp-4);
  display: flex; align-items: center; gap: var(--sp-2);
}
.term-ps  { color: var(--accent); }
.term-cmd { color: var(--fg-2); }

.cursor {
  display: inline-block; width: 0.55em; height: 1em;
  background: var(--accent); vertical-align: text-bottom;
  margin-left: 3px; border-radius: 1px;
  animation: cur-blink 1.1s step-end infinite;
}
@keyframes cur-blink { 0%,100%{opacity:1} 50%{opacity:0} }

.term-output {
  font-family: var(--font-mono); font-size: var(--fs-sm);
  display: flex; flex-direction: column; gap: var(--sp-3);
  border-left: 2px solid var(--border); padding-left: var(--sp-5);
}
.term-out-row { display: grid; grid-template-columns: 80px 20px 1fr; gap: var(--sp-2); align-items: baseline; }
.term-key { color: var(--fg-3); }
.term-sep { color: var(--accent); }
.term-val { color: var(--fg-2); line-height: var(--lh-snug); }

/* ─── LeetCode stats ─────────────────────────────────────────── */
.lc-block {
  display: flex; flex-direction: column; gap: var(--sp-4);
  background: var(--bg-elev); border: 1px solid var(--border);
  border-radius: var(--r-md); padding: var(--sp-6);
  transition: border-color var(--dur-2) var(--ease-std);
}
.lc-total { font-size: var(--fs-lg); font-weight: 500; color: var(--fg-1); }
.lc-total small { font-size: var(--fs-sm); font-weight: 400; color: var(--fg-3); margin-left: var(--sp-2); }
.lc-rows { display: flex; flex-direction: column; gap: var(--sp-3); }
.lc-row { display: grid; grid-template-columns: 64px 1fr 40px; gap: var(--sp-3); align-items: center; }
.lc-label { font-size: var(--fs-sm); color: var(--fg-3); }
.lc-bar { height: 4px; background: var(--border); border-radius: 2px; overflow: hidden; }
.lc-fill { height: 100%; border-radius: 2px; transition: width 1s ease; }
.lc-fill.easy   { background: #4ade80; }
.lc-fill.medium { background: var(--accent); }
.lc-fill.hard   { background: #f87171; }
.lc-count { font-size: var(--fs-sm); color: var(--fg-2); text-align: right; }
.lc-err   { font-size: var(--fs-sm); color: var(--fg-3); }


/* ─── Command palette ────────────────────────────────────────── */
#cmd-palette {
  position: fixed; inset: 0; z-index: 9999;
  background: color-mix(in oklab, var(--bg) 75%, transparent);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  display: flex; align-items: flex-start; justify-content: center;
  padding-top: 14vh;
  opacity: 0; pointer-events: none;
  transition: opacity var(--dur-2) var(--ease-std);
}
#cmd-palette.open { opacity: 1; pointer-events: all; }
#cmd-panel {
  background: var(--bg-elev); border: 1px solid var(--border-strong);
  border-radius: var(--r-md); width: 100%; max-width: 560px;
  overflow: hidden;
  box-shadow: 0 24px 64px color-mix(in oklab, #000 28%, transparent);
}
#cmd-input-wrap {
  display: flex; align-items: center; gap: var(--sp-3);
  padding: var(--sp-4) var(--sp-5); border-bottom: 1px solid var(--border);
}
#cmd-search-ico { width: 15px; height: 15px; color: var(--fg-3); flex-shrink: 0; stroke-width: 2; }
#cmd-input {
  background: none; border: none; outline: none; flex: 1;
  font-size: var(--fs-base); color: var(--fg-1);
  caret-color: var(--accent);
}
#cmd-input::placeholder { color: var(--fg-3); }
#cmd-esc-hint {
  font-family: var(--font-mono); font-size: var(--fs-3xs);
  color: var(--fg-3); border: 1px solid var(--border);
  border-radius: var(--r-xs); padding: 2px 6px; flex-shrink: 0;
}
#cmd-list {
  list-style: none; margin: 0; padding: var(--sp-2) 0;
  max-height: 320px; overflow-y: auto;
}
.cmd-item {
  display: flex; align-items: center; gap: var(--sp-3);
  padding: var(--sp-3) var(--sp-5); cursor: pointer;
  transition: background var(--dur-1) var(--ease-std);
}
.cmd-item.cmd-active,
.cmd-item:hover { background: color-mix(in oklab, var(--accent) 8%, transparent); }
.cmd-item-label { font-size: var(--fs-sm); font-weight: 500; color: var(--fg-1); min-width: 88px; }
.cmd-item-desc  { font-size: var(--fs-xs); color: var(--fg-3); flex: 1; }
.cmd-item-ext   { width: 11px; height: 11px; color: var(--fg-3); flex-shrink: 0; stroke-width: 2; }
#cmd-footer {
  border-top: 1px solid var(--border); padding: var(--sp-3) var(--sp-5);
  display: flex; gap: var(--sp-5);
}
.cmd-hint {
  font-family: var(--font-mono); font-size: var(--fs-3xs); color: var(--fg-3);
  display: flex; align-items: center; gap: var(--sp-2);
}
.cmd-hint kbd {
  border: 1px solid var(--border); border-radius: var(--r-xs);
  padding: 1px 5px; color: var(--fg-3);
}

/* ─── Scroll fade-in ─────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(12px);
  filter: blur(3px);
  will-change: opacity, transform, filter;
  transition:
    opacity   0.7s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.7s cubic-bezier(0.16, 1, 0.3, 1),
    filter    0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible {
  opacity: 1;
  transform: none;
  filter: blur(0px);
}

/* ─── Back to top ───────────────────────────────────────────── */
#back-to-top {
  position: fixed; bottom: var(--sp-7); right: var(--sp-7); z-index: 9990;
  background: var(--bg-elev); border: 1px solid var(--border);
  border-radius: var(--r-sm); padding: 8px 10px; color: var(--fg-3);
  cursor: pointer; display: flex; align-items: center; justify-content: center;
  opacity: 0; pointer-events: none; transform: translateY(6px);
  transition: opacity var(--dur-2) var(--ease-std), transform var(--dur-2) var(--ease-std),
              border-color var(--dur-1) var(--ease-std), color var(--dur-1) var(--ease-std);
}
#back-to-top.visible { opacity: 1; pointer-events: all; transform: none; }
#back-to-top:hover   { border-color: var(--border-strong); color: var(--fg-1); }
#back-to-top .ico    { width: 14px; height: 14px; }

/* ─── Mobile nav ─────────────────────────────────────────────── */
#nav-hamburger {
  display: none; background: none; border: none; cursor: pointer;
  padding: 4px; color: var(--fg-2); align-items: center;
  transition: color var(--dur-1) var(--ease-std);
}
#nav-hamburger:hover { color: var(--fg-1); }
#nav-hamburger .ico  { width: 18px; height: 18px; }

#nav-mobile {
  position: fixed; inset: 0; z-index: 9990;
  background: var(--bg); display: flex; flex-direction: column;
  padding: var(--sp-6) var(--sp-7);
  opacity: 0; pointer-events: none;
  transition: opacity var(--dur-2) var(--ease-std);
}
#nav-mobile.open     { opacity: 1; pointer-events: all; }
#nav-mobile-head     { display: flex; justify-content: space-between; align-items: center; }
#nav-mobile-close    {
  background: none; border: none; cursor: pointer; padding: 4px;
  color: var(--fg-3); transition: color var(--dur-1) var(--ease-std);
}
#nav-mobile-close:hover { color: var(--fg-1); }
#nav-mobile-close .ico  { width: 20px; height: 20px; }
.nav-mobile-links    {
  display: flex; flex-direction: column; gap: var(--sp-5); margin-top: var(--sp-10);
}
.nav-mobile-links a  {
  font-family: var(--font-display); font-size: clamp(32px, 9vw, 52px);
  font-weight: 400; letter-spacing: -0.02em; color: var(--fg-3);
  text-decoration: none; transition: color var(--dur-1) var(--ease-std);
}
.nav-mobile-links a:hover,
.nav-mobile-links a[aria-current] { color: var(--fg-1); }

@media (max-width: 680px) {
  .nav-links        { display: none !important; }
  #nav-hamburger    { display: flex; }
}

/* ─── Reading progress ───────────────────────────────────────── */
#read-progress {
  position: fixed; top: 0; left: 0; height: 2px; z-index: 9999;
  background: var(--accent); width: 0%;
  transition: width 80ms linear;
  pointer-events: none;
  transform-origin: left;
}

/* ─── Cross-document view transitions (Chrome 126+) ─────────── */
@supports (view-transition-name: none) {
  @view-transition { navigation: auto; }
  ::view-transition-old(root) { animation: 140ms ease-out both vt-fade-out; }
  ::view-transition-new(root) { animation: 180ms ease-out both vt-fade-in; }
}
@keyframes vt-fade-out { to   { opacity: 0; } }
@keyframes vt-fade-in  { from { opacity: 0; } }

/* ─── Hero entrance — single staggered fade-up on load ───────── */
@media (prefers-reduced-motion: no-preference) {
  .hero > * {
    opacity: 0;
    transform: translateY(10px);
    animation: hero-rise 0.62s cubic-bezier(0.16, 1, 0.3, 1) both;
  }
  .hero > *:nth-child(1) { animation-delay: 0.04s; }
  .hero > *:nth-child(2) { animation-delay: 0.11s; }
  .hero > *:nth-child(3) { animation-delay: 0.18s; }
  .hero > *:nth-child(4) { animation-delay: 0.25s; }
  .hero > *:nth-child(5) { animation-delay: 0.32s; }
}
@keyframes hero-rise { to { opacity: 1; transform: none; } }

/* ─── Reduced motion ─────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  .reveal,
  .reveal.visible {
    opacity: 1; transform: none; filter: none; transition: none;
  }
  #back-to-top,
  #nav-mobile,
  #cmd-palette { transition: none !important; }
  ::view-transition-old(root),
  ::view-transition-new(root) { animation: none; }
}

/* ─── Responsive ─────────────────────────────────────────────── */
@media (max-width: 640px) {
  .wrap, .nav-inner { padding-left: var(--sp-5); padding-right: var(--sp-5); }
  .row-item { grid-template-columns: 48px 1fr; }
  .row-tag  { display: none; }
  .lc-row   { grid-template-columns: 56px 1fr auto; }
  .term-out-row { grid-template-columns: 68px 16px 1fr; }
}

/* ─── Hide film grain on mobile ──────────────────────────── */
@media (max-width: 640px) {
  #noise-overlay { display: none; }
}