/* ==========================================================================
   Oviich — YouTube Downloader
   Fixed-viewport UI with a 3D depth-stack transition between panels.
   ========================================================================== */

:root{
  --bg:#07070c;
  --ink:#f5f5f7;
  --ink-dim:#a1a1ac;
  --ink-faint:#6b6b76;

  --glass:rgba(255,255,255,.045);
  --glass-strong:rgba(255,255,255,.08);
  --glass-border:rgba(255,255,255,.09);

  --red:#ff3b5c;
  --pink:#ff5d9e;
  --violet:#8b5cf6;
  --blue:#4f7dfb;

  --grad:linear-gradient(120deg,var(--red),var(--pink) 45%,var(--violet) 85%);

  --radius-lg:28px;
  --radius-md:18px;

  --ease:cubic-bezier(.16,1,.3,1);

  --font-display:'Space Grotesk','Inter',system-ui,sans-serif;
  --font-body:'Inter',system-ui,-apple-system,sans-serif;

  --vh:1vh;
}

/* ---------- Reset & base -------------------------------------------------- */

*,*::before,*::after{ box-sizing:border-box; }

/* An element's own `display:flex/grid` rule otherwise wins over the
   browser's default [hidden]{display:none} — same specificity, author
   origin beats user-agent origin. Force hidden to always mean hidden. */
[hidden]{ display:none !important; }

html,body{
  margin:0;
  height:calc(var(--vh) * 100);
  height:100dvh;
  overflow:hidden;
  overscroll-behavior:none;
  background:var(--bg);
}

body{
  position:fixed;
  inset:0;
  width:100%;
  color:var(--ink);
  font-family:var(--font-body);
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  touch-action:none;
}

input,button,textarea,select{ font-family:inherit; touch-action:manipulation; }
button{ -webkit-tap-highlight-color:transparent; }
a{ color:inherit; }

h1,h2,p{ margin:0; }

img{ max-width:100%; display:block; }

/* ---------- Ambient background -------------------------------------------- */

.noise{
  position:fixed; inset:0; z-index:1; pointer-events:none;
  opacity:.035; mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.aurora{ position:fixed; inset:0; z-index:0; overflow:hidden; pointer-events:none; }
.blob{ position:absolute; border-radius:50%; filter:blur(90px); opacity:.5; mix-blend-mode:screen; }
.b1{ width:52vw; height:52vw; top:-14%; left:-12%; background:radial-gradient(circle,var(--red),transparent 70%); animation:float1 22s ease-in-out infinite; }
.b2{ width:46vw; height:46vw; bottom:-16%; right:-10%; background:radial-gradient(circle,var(--violet),transparent 70%); animation:float2 26s ease-in-out infinite; }
.b3{ width:34vw; height:34vw; top:38%; left:58%; background:radial-gradient(circle,var(--blue),transparent 70%); animation:float3 30s ease-in-out infinite; }

@keyframes float1{ 0%,100%{ transform:translate(0,0) scale(1); } 50%{ transform:translate(6vw,8vh) scale(1.15); } }
@keyframes float2{ 0%,100%{ transform:translate(0,0) scale(1); } 50%{ transform:translate(-7vw,-5vh) scale(1.1); } }
@keyframes float3{ 0%,100%{ transform:translate(0,0) scale(1); } 50%{ transform:translate(-5vw,6vh) scale(.9); } }

/* ---------- Topbar & nav dots ---------------------------------------------- */

.topbar{
  position:fixed; top:0; left:0; right:0; z-index:20;
  display:flex; align-items:center; justify-content:space-between;
  padding:clamp(14px,3vw,26px) clamp(18px,4vw,44px);
  pointer-events:none;
}
.brand{
  font-family:var(--font-display); font-weight:700; font-size:clamp(.95rem,1.6vw,1.1rem);
  letter-spacing:.01em; display:flex; align-items:center; gap:8px; pointer-events:auto;
}
.brand-mark{
  display:inline-flex; align-items:center; justify-content:center;
  width:24px; height:24px; border-radius:8px; background:var(--grad);
  font-size:.65rem; color:#fff;
}
.brand-sub{ color:var(--ink-faint); font-weight:500; }
.topbar-badge{
  font-size:.72rem; color:var(--ink-dim);
  padding:6px 13px; border-radius:999px;
  background:var(--glass); border:1px solid var(--glass-border);
  backdrop-filter:blur(12px); -webkit-backdrop-filter:blur(12px);
  pointer-events:auto;
}
.topbar-badge strong{ background:var(--grad); -webkit-background-clip:text; background-clip:text; color:transparent; }

.dots{
  position:fixed; right:clamp(12px,3vw,30px); top:50%; transform:translateY(-50%);
  z-index:20; display:flex; flex-direction:column; gap:14px;
}
.dot{
  width:9px; height:9px; border-radius:50%;
  background:transparent; border:1.5px solid rgba(255,255,255,.32);
  cursor:pointer; padding:0; position:relative;
  transition:all .3s var(--ease);
}
.dot span{ position:absolute; inset:-11px; }
.dot:hover{ border-color:rgba(255,255,255,.7); }
.dot.active{
  background:var(--grad); border-color:transparent; transform:scale(1.35);
  box-shadow:0 0 14px rgba(255,60,110,.65);
}

/* ---------- Scene / 3D panel stack ----------------------------------------- */

.scene{
  position:fixed; inset:0; z-index:2;
  height:calc(var(--vh) * 100); height:100dvh; width:100%;
  perspective:1800px; perspective-origin:50% 50%;
  overflow:hidden;
}

.panel{
  position:absolute; inset:0;
  display:flex; align-items:center; justify-content:center;
  padding:clamp(20px,5vw,80px);
  padding-top:clamp(70px,10vh,110px);
  transform-style:preserve-3d;
  transition:transform 950ms var(--ease), opacity 750ms var(--ease), filter 750ms var(--ease);
  will-change:transform, opacity, filter;
}
.panel > *{ position:relative; }

.panel[data-state="active"]{ transform:translateZ(0) translateY(0) rotateX(0deg) scale(1); opacity:1; filter:blur(0px); pointer-events:auto; z-index:5; }
.panel[data-state="next"]{ transform:translateZ(-560px) translateY(8%) rotateX(11deg) scale(.86); opacity:0; filter:blur(6px); pointer-events:none; z-index:3; }
.panel[data-state="prev"]{ transform:translateZ(-560px) translateY(-8%) rotateX(-11deg) scale(.86); opacity:0; filter:blur(6px); pointer-events:none; z-index:3; }
.panel[data-state="far"]{ transform:translateZ(-980px) scale(.7); opacity:0; filter:blur(10px); pointer-events:none; z-index:1; }

.enter{ animation:rise-in .7s var(--ease); }
@keyframes rise-in{ from{ opacity:0; transform:translateY(18px); } to{ opacity:1; transform:translateY(0); } }

/* ---------- Shared bits ----------------------------------------------------- */

.grad-text{ background:var(--grad); -webkit-background-clip:text; background-clip:text; color:transparent; }

.kicker{
  display:inline-flex; align-items:center; gap:8px;
  font-size:.78rem; color:var(--ink-dim);
  padding:7px 16px; border-radius:999px;
  background:var(--glass); border:1px solid var(--glass-border);
  backdrop-filter:blur(12px); -webkit-backdrop-filter:blur(12px);
}
.pulse-dot{ width:7px; height:7px; border-radius:50%; background:var(--red); display:inline-block; animation:pulse 2s infinite; }
@keyframes pulse{
  0%{ box-shadow:0 0 0 0 rgba(255,59,92,.55); }
  70%{ box-shadow:0 0 0 8px rgba(255,59,92,0); }
  100%{ box-shadow:0 0 0 0 rgba(255,59,92,0); }
}

.btn-primary{
  position:relative; overflow:hidden;
  display:inline-flex; align-items:center; justify-content:center; gap:8px;
  padding:14px 26px; border-radius:999px; border:none; cursor:pointer;
  background:var(--grad); color:#fff; font-weight:600; font-size:.95rem;
  font-family:var(--font-body);
  box-shadow:0 8px 24px -6px rgba(255,59,92,.5);
  transition:transform .25s var(--ease), box-shadow .25s, opacity .2s;
  flex-shrink:0; white-space:nowrap;
}
.btn-primary:hover:not(:disabled){ transform:translateY(-2px); box-shadow:0 12px 28px -6px rgba(255,59,92,.65); }
.btn-primary:active:not(:disabled){ transform:translateY(0) scale(.98); }
.btn-primary:disabled{ opacity:.45; cursor:not-allowed; box-shadow:none; }
.btn-arrow{ width:18px; height:18px; transition:transform .25s; }
.btn-primary:hover .btn-arrow{ transform:translateX(3px); }
.btn-icon-download{ width:17px; height:17px; }

.btn-spinner{
  display:none; width:16px; height:16px; border-radius:50%; flex-shrink:0;
  border:2px solid rgba(255,255,255,.4); border-top-color:#fff;
  animation:spin .7s linear infinite;
}
.btn-primary.is-loading .btn-label,
.btn-primary.is-loading .btn-arrow,
.btn-primary.is-loading .btn-icon-download{ display:none; }
.btn-primary.is-loading .btn-spinner{ display:inline-block; }
@keyframes spin{ to{ transform:rotate(360deg); } }

.btn-ghost{
  background:none; border:1px solid var(--glass-border); color:var(--ink-dim);
  padding:12px 20px; border-radius:999px; cursor:pointer;
  font-size:.85rem; font-weight:500; transition:all .2s; white-space:nowrap;
}
.btn-ghost:hover{ border-color:rgba(255,255,255,.3); color:var(--ink); }

/* ==========================================================================
   Panel 0 — Hero
   ========================================================================== */

.panel-hero{ flex-direction:column; text-align:center; perspective:1000px; }

.hero-cards{ position:absolute; inset:0; pointer-events:none; z-index:0; transform-style:preserve-3d; transition:transform .35s ease-out; }
.float-card{
  position:absolute; width:168px; padding:10px; border-radius:16px;
  background:var(--glass); border:1px solid var(--glass-border);
  backdrop-filter:blur(14px); -webkit-backdrop-filter:blur(14px);
  box-shadow:0 20px 40px -20px rgba(0,0,0,.6);
  transform:rotate(var(--r,0deg));
  animation:drift 9s ease-in-out infinite;
  animation-delay:var(--d,0s);
}
.fc-thumb{
  width:100%; aspect-ratio:16/10; border-radius:10px; position:relative;
  background:linear-gradient(135deg,rgba(255,59,92,.4),rgba(139,92,246,.4));
}
.fc-thumb::after{
  content:''; position:absolute; top:50%; left:50%; transform:translate(-45%,-50%);
  width:0; height:0; border-style:solid; border-width:8px 0 8px 13px;
  border-color:transparent transparent transparent rgba(255,255,255,.9);
}
.fc-line{ height:6px; border-radius:3px; background:rgba(255,255,255,.16); margin-top:8px; }
.fc-line.short{ width:55%; margin-top:6px; }

.fc1{ --r:-9deg; --d:0s; top:15%; left:6%; }
.fc2{ --r:7deg; --d:1.1s; bottom:13%; left:9%; width:136px; }
.fc3{ --r:10deg; --d:2.2s; top:19%; right:6%; }

@keyframes drift{
  0%,100%{ transform:translateY(0) rotate(var(--r,0deg)); }
  50%{ transform:translateY(-16px) rotate(var(--r,0deg)); }
}

.hero-content{
  max-width:720px; display:flex; flex-direction:column; align-items:center; gap:16px; z-index:1;
}
.hero-title{
  font-family:var(--font-display); font-weight:700;
  font-size:clamp(2rem,5.6vw,4.4rem); line-height:1.06; letter-spacing:-.02em;
}
.hero-sub{ color:var(--ink-dim); font-size:clamp(.92rem,1.5vw,1.1rem); max-width:520px; line-height:1.55; }

.url-form{ display:flex; gap:10px; width:min(600px,88vw); margin-top:6px; flex-wrap:wrap; justify-content:center; }
.url-input-wrap{
  flex:1 1 300px; display:flex; align-items:center; gap:10px;
  background:var(--glass); border:1px solid var(--glass-border);
  backdrop-filter:blur(16px); -webkit-backdrop-filter:blur(16px);
  border-radius:999px; padding:5px 7px 5px 18px;
  transition:border-color .25s, box-shadow .25s;
}
.url-input-wrap:focus-within{ border-color:rgba(255,93,158,.55); box-shadow:0 0 0 4px rgba(255,59,92,.12); }
.url-icon{ width:19px; height:19px; color:var(--ink-faint); flex-shrink:0; }
#url-input{
  flex:1; min-width:0; background:none; border:none; outline:none;
  color:var(--ink); font-size:.95rem; padding:11px 0;
}
#url-input::placeholder{ color:var(--ink-faint); }
.icon-btn{
  width:36px; height:36px; border-radius:50%; flex-shrink:0;
  display:flex; align-items:center; justify-content:center;
  background:rgba(255,255,255,.06); border:1px solid var(--glass-border); color:var(--ink-dim);
  cursor:pointer; transition:all .2s;
}
.icon-btn:hover{ background:rgba(255,255,255,.13); color:var(--ink); }
.icon-btn svg{ width:16px; height:16px; }

@keyframes shake{
  10%,90%{ transform:translateX(-1px); }
  20%,80%{ transform:translateX(2px); }
  30%,50%,70%{ transform:translateX(-4px); }
  40%,60%{ transform:translateX(4px); }
}
.shake{ animation:shake .4s; }

.form-error{ color:var(--red); font-size:.83rem; min-height:1.2em; }
.trust-row{ display:flex; gap:10px; align-items:center; color:var(--ink-faint); font-size:.78rem; }
.trust-row .sep{ opacity:.5; }

.scroll-hint{
  position:absolute; bottom:clamp(14px,3vh,28px); left:50%; transform:translateX(-50%);
  display:flex; flex-direction:column; align-items:center; gap:4px;
  background:none; border:none; color:var(--ink-faint); cursor:pointer;
  font-size:.72rem; letter-spacing:.08em; text-transform:uppercase;
  animation:bob 2.2s ease-in-out infinite;
  transition:opacity .4s, transform .4s;
}
.scroll-hint svg{ width:17px; height:17px; }
.scroll-hint.is-hidden{ opacity:0; pointer-events:none; transform:translate(-50%,10px); }
@keyframes bob{ 0%,100%{ transform:translate(-50%,0); } 50%{ transform:translate(-50%,6px); } }

/* ==========================================================================
   Panel 1 — Tool / Result
   ========================================================================== */

.tool-card{
  width:min(880px,92vw);
  max-height:min(640px,80dvh);
  background:var(--glass); border:1px solid var(--glass-border);
  border-radius:var(--radius-lg);
  backdrop-filter:blur(22px); -webkit-backdrop-filter:blur(22px);
  box-shadow:0 30px 70px -30px rgba(0,0,0,.7);
  padding:clamp(20px,3vw,36px);
  display:flex; align-items:center; justify-content:center;
  overflow:auto;
}
.tool-card::-webkit-scrollbar{ width:0; height:0; }

.tool-empty, .tool-error-state{
  display:flex; flex-direction:column; align-items:center; gap:14px;
  color:var(--ink-dim); text-align:center; max-width:360px; font-size:.92rem;
}
.empty-orb{
  width:60px; height:60px; border-radius:50%; background:var(--grad);
  display:flex; align-items:center; justify-content:center; flex-shrink:0;
  box-shadow:0 0 40px rgba(255,59,92,.35);
}
.empty-orb svg{ width:22px; height:22px; }
.error-orb{
  background:linear-gradient(120deg,#ff3b5c,#ff5d9e);
  color:#fff; font-family:var(--font-display); font-weight:700; font-size:1.3rem;
  box-shadow:0 0 40px rgba(255,59,92,.35);
}

.tool-loading{ display:flex; flex-direction:column; align-items:center; gap:16px; width:100%; max-width:420px; }
.skeleton-thumb{
  width:100%; aspect-ratio:16/9; border-radius:16px;
  background-image:linear-gradient(100deg, rgba(255,255,255,.05) 30%, rgba(255,255,255,.11) 50%, rgba(255,255,255,.05) 70%);
  background-size:200% 100%;
  animation:shimmer 1.5s infinite;
}
.skeleton-lines{ width:100%; display:flex; flex-direction:column; gap:8px; }
.skel-line{
  height:12px; border-radius:6px; background-size:200% 100%;
  background-image:linear-gradient(100deg, rgba(255,255,255,.04) 30%, rgba(255,255,255,.12) 50%, rgba(255,255,255,.04) 70%);
  animation:shimmer 1.5s infinite;
}
.skel-line.w70{ width:70%; }
.skel-line.w40{ width:40%; }
@keyframes shimmer{ 0%{ background-position:200% 0; } 100%{ background-position:-200% 0; } }
.loading-text{ color:var(--ink-faint); font-size:.82rem; }

.tool-result{
  display:grid; grid-template-columns:minmax(200px,320px) 1fr;
  gap:clamp(18px,3vw,32px); width:100%; align-items:start;
}
.thumb-wrap{
  position:relative; border-radius:16px; overflow:hidden;
  aspect-ratio:16/9; background:#000;
  transform:perspective(800px) rotateY(0deg);
  transition:transform .4s var(--ease);
}
.thumb-wrap:hover{ transform:perspective(800px) rotateY(-6deg) rotateX(2deg); }
.thumb-wrap img{ width:100%; height:100%; object-fit:cover; }
.live-badge{
  position:absolute; top:10px; left:10px; background:var(--red); color:#fff;
  font-size:.68rem; font-weight:700; padding:4px 9px; border-radius:6px;
  letter-spacing:.03em; animation:pulse 2s infinite;
}
.duration-badge{
  position:absolute; bottom:10px; right:10px; background:rgba(0,0,0,.75);
  color:#fff; font-size:.72rem; font-weight:600; padding:3px 8px; border-radius:6px;
}

.result-info{ display:flex; flex-direction:column; gap:8px; min-width:0; }
.result-title{
  font-family:var(--font-display); font-weight:600; font-size:clamp(1.05rem,1.9vw,1.4rem);
  line-height:1.28;
  display:-webkit-box; -webkit-line-clamp:2; -webkit-box-orient:vertical; overflow:hidden;
}
.result-uploader{ color:var(--ink-dim); font-size:.84rem; }
.live-note{ color:var(--pink); font-size:.76rem; }

.quality-block{ margin-top:8px; }
.block-label{ font-size:.7rem; text-transform:uppercase; letter-spacing:.08em; color:var(--ink-faint); display:block; margin-bottom:8px; }
.quality-grid{ display:flex; flex-wrap:wrap; gap:8px; }
.quality-grid:empty{ display:none; }
.qchip{
  padding:8px 14px; border-radius:10px;
  background:rgba(255,255,255,.045); border:1px solid var(--glass-border);
  color:var(--ink-dim); font-size:.8rem; font-weight:500; cursor:pointer;
  display:flex; flex-direction:column; align-items:flex-start; gap:1px;
  transition:all .2s;
}
.qchip .qsize{ font-size:.66rem; color:var(--ink-faint); }
.qchip:hover{ border-color:rgba(255,255,255,.28); color:var(--ink); }
.qchip.selected{ background:var(--grad); border-color:transparent; color:#fff; box-shadow:0 6px 18px -6px rgba(255,59,92,.55); }
.qchip.selected .qsize{ color:rgba(255,255,255,.85); }

.download-row{ display:flex; align-items:center; gap:12px; margin-top:12px; flex-wrap:wrap; }

.progress-wrap{ width:100%; margin-top:12px; }
.progress-bar{ width:100%; height:8px; border-radius:999px; background:rgba(255,255,255,.08); overflow:hidden; }
.progress-fill{ height:100%; width:0%; background:var(--grad); border-radius:999px; transition:width .3s ease; }
.progress-meta{ display:flex; justify-content:space-between; gap:8px; font-size:.7rem; color:var(--ink-faint); margin-top:6px; }
.tool-error{ color:var(--red); font-size:.83rem; margin-top:4px; min-height:1.1em; }

/* ==========================================================================
   Panel 2 — Footer
   ========================================================================== */

.panel-footer{ text-align:center; }
.footer-content{ display:flex; flex-direction:column; align-items:center; gap:14px; max-width:540px; }
.footer-kicker{ color:var(--ink-faint); font-size:.85rem; }
.footer-signature{ font-family:var(--font-display); font-weight:700; font-size:clamp(1.7rem,4.2vw,2.9rem); }
.footer-note{ color:var(--ink-dim); font-size:.9rem; line-height:1.55; }
.footer-power{ color:var(--ink-faint); font-size:.8rem; }
.footer-power a{ color:var(--ink-dim); text-decoration:underline; text-underline-offset:2px; }
.footer-power a:hover{ color:var(--ink); }

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width:860px){
  .hero-cards{ display:none; }
}

@media (max-width:720px){
  .tool-result{ grid-template-columns:1fr; }
  .thumb-wrap{ max-height:26dvh; }
  .tool-card{ max-height:88dvh; }
}

@media (max-width:520px){
  .topbar-badge{ display:none; }
  .dots{ right:8px; gap:11px; }
  .hero-title{ font-size:clamp(1.7rem,8vw,2.6rem); }
  .btn-ghost{ padding:10px 16px; font-size:.8rem; }
  .panel{ padding-top:64px; }
}

@media (max-height:640px){
  .panel{ padding-top:58px; }
  .hero-content{ gap:10px; }
  .tool-card{ max-height:84dvh; }
}

/* ---------- Reduced motion --------------------------------------------------- */

@media (prefers-reduced-motion:reduce){
  .blob,.float-card,.pulse-dot,.live-badge,.scroll-hint,.skeleton-thumb,.skel-line{ animation:none !important; }
  .panel{ transition:opacity .25s ease !important; }
  .panel[data-state]{ transform:none !important; }
  .enter{ animation:none !important; }
}