*{box-sizing:border-box}
:root{
  font-family:'Plus Jakarta Sans',Inter,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  color:#f8fafc;
  background:#070a12;
  color-scheme:dark;
  --hub-primary:#e11d48; /* Màu đỏ Gaming hiện đại */
  --hub-primary-hover:#f43f5e;
  --hub-glow:rgba(225,29,72,0.25);
  --card-bg:rgba(18,26,43,0.85);
  --card-border:rgba(255,255,255,0.08);
}
html,body{
  margin:0;
  min-height:100%;
  background-color:#070a12;
  background-image:
    radial-gradient(at 0% 0%, rgba(225,29,72,0.12) 0px, transparent 45%),
    radial-gradient(at 100% 100%, rgba(56,189,248,0.08) 0px, transparent 45%);
  background-attachment:fixed;
}
body{padding:0}
button,input,textarea,select{font:inherit}
button{cursor:pointer}

/* App Shell */
.app-shell{max-width:1500px;margin:0 auto;padding:16px 24px 36px}
.app-header{
  position:sticky;top:54px;z-index:20;
  display:flex;justify-content:space-between;align-items:center;gap:20px;
  padding:14px 20px;
  background:rgba(18,26,43,0.88);
  border:1px solid var(--card-border);
  border-radius:16px;
  backdrop-filter:blur(16px);
  -webkit-backdrop-filter:blur(16px);
  margin-bottom:16px;
}
.brand{display:flex;align-items:center;gap:12px;min-width:0}
.brand-mark{
  width:44px;height:44px;
  display:grid;place-items:center;
  border-radius:12px;
  background:linear-gradient(135deg, #e11d48, #be123c);
  color:#fff;font-weight:900;letter-spacing:-1px;
  box-shadow:0 4px 14px var(--hub-glow);
}
.brand h1{font-size:18px;line-height:1.2;margin:0 0 3px;letter-spacing:-.3px;color:#fff}
.brand p{margin:0;color:#94a3b8;font-size:12px}

/* Header Buttons */
.header-actions{display:flex;gap:8px}
.btn{
  border:1px solid var(--card-border);
  border-radius:10px;padding:9px 16px;
  font-weight:700;min-height:40px;
  font-size:13px;transition:all .2s ease;
}
.btn-primary{
  background:var(--hub-primary);
  color:#fff;
  border-color:var(--hub-primary);
  box-shadow:0 4px 14px var(--hub-glow);
}
.btn-primary:hover{background:var(--hub-primary-hover);transform:translateY(-1px)}
.btn-ghost{background:rgba(255,255,255,0.05);color:#cbd5e1}
.btn-ghost:hover{background:rgba(255,255,255,0.1);color:#fff}

/* Tip bar */
.mobile-tip{
  display:flex;gap:8px;align-items:center;
  padding:10px 16px;margin:0 0 16px;
  border:1px solid rgba(225,29,72,0.25);
  background:rgba(225,29,72,0.08);
  border-radius:12px;color:#fecdd3;font-size:12px;
}

/* Workspace Layout */
.workspace{display:grid;grid-template-columns:minmax(320px,400px) minmax(0,1fr);gap:22px;align-items:start}
.editor-panel{
  background:var(--card-bg);
  border:1px solid var(--card-border);
  border-radius:20px;padding:22px;
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
  box-shadow:0 20px 40px -15px rgba(0,0,0,0.6);
}
.section-heading{margin-bottom:16px}
.eyebrow{
  display:block;text-transform:uppercase;letter-spacing:.11em;
  font-size:10px;font-weight:800;color:var(--hub-primary);margin-bottom:4px;
}
.section-heading h2{margin:0;font-size:17px;color:#fff}
.field{margin-bottom:14px}
label{display:block;font-size:12px;font-weight:700;margin-bottom:7px;color:#cbd5e1}
.label-row{display:flex;justify-content:space-between;align-items:center}
.counter{font-size:10px;color:#64748b}

/* Form Controls */
textarea,input[type=file],select,input[type=number]{
  width:100%;
  border:1px solid var(--card-border);
  border-radius:10px;
  background:rgba(7,10,18,0.6);
  padding:10px 12px;
  color:#fff;
  outline:none;
  transition:all .2s ease;
}
textarea{resize:vertical;line-height:1.45;min-height:76px}
textarea:focus,input:focus,select:focus{
  outline:none;
  border-color:var(--hub-primary);
  box-shadow:0 0 0 3px rgba(225,29,72,0.2);
}

.file-input{position:absolute;width:1px!important;height:1px;opacity:0;pointer-events:none}
.dropzone{
  border:1.5px dashed rgba(255,255,255,0.18);
  border-radius:13px;padding:18px 12px;text-align:center;
  background:rgba(7,10,18,0.4);
  color:#94a3b8;transition:.18s;
}
.dropzone:hover,.dropzone:focus,.dropzone.drag{
  border-color:var(--hub-primary);
  background:rgba(225,29,72,0.06);
  outline:none;
}
.drop-icon{font-size:22px;font-weight:900;line-height:1;margin-bottom:6px;color:var(--hub-primary)}
.dropzone strong,.dropzone span,.dropzone small{display:block}
.dropzone strong{font-size:13px;color:#fff;margin-bottom:4px}
.dropzone span{font-size:11px;color:#94a3b8}
.dropzone small{font-size:10px;color:#64748b;margin-top:6px}
.status{min-height:17px;margin-top:5px;color:#22c55e;font-size:11px}

/* Settings Accordion */
.settings{
  border:1px solid var(--card-border);
  border-radius:12px;
  background:rgba(255,255,255,0.02);
  padding:12px 14px;
  margin-top:12px;
}
.settings summary{cursor:pointer;font-size:12px;font-weight:700;color:#f8fafc;list-style:none}
.settings summary::-webkit-details-marker{display:none}
.settings summary:after{content:"+";float:right;color:#64748b}
.settings[open] summary:after{content:"−"}
.settings[open] summary{margin-bottom:12px}
.settings-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.slider-row{display:grid;grid-template-columns:42px 1fr 52px;align-items:center;gap:8px;margin:10px 0;font-size:11px;color:#94a3b8}
.slider-row output{text-align:right;color:#cbd5e1;font-variant-numeric:tabular-nums}
input[type=range]{padding:0;accent-color:var(--hub-primary)}

/* Preview Panel */
.preview-panel{min-width:0}
.preview-toolbar{
  display:flex;justify-content:space-between;align-items:end;
  margin:2px 0 12px;padding:0 4px;
}
.preview-toolbar strong{font-size:13px;color:#fff}
.ready-dot{font-size:11px;color:#22c55e;display:flex;gap:6px;align-items:center;font-weight:600}
.ready-dot i{width:7px;height:7px;border-radius:50%;background:#22c55e;box-shadow:0 0 8px #22c55e;display:inline-block}
.preview-wrap{
  width:min(86vh,900px,100%);max-width:100%;
  margin:0 auto;border-radius:16px;overflow:hidden;
  background:#000;border:1px solid var(--card-border);
  box-shadow:0 20px 50px rgba(0,0,0,.6);
}
canvas{display:block;width:100%;height:auto}
.preview-hint{text-align:center;color:#64748b;font-size:11px;margin:12px 0}

/* Responsive */
@media(max-width:1050px){
  .workspace{grid-template-columns:340px minmax(0,1fr);gap:16px}
  .app-shell{padding-left:16px;padding-right:16px}
}
@media(max-width:820px){
  .app-header{position:static}
  .workspace{grid-template-columns:1fr}
  .editor-panel{order:2}
  .preview-panel{order:1}
  .preview-wrap{width:min(92vw,720px)}
  .mobile-tip{font-size:11px}
}
@media(max-width:560px){
  .app-shell{padding:10px 10px 24px}
  .app-header{align-items:flex-start;padding:10px 14px}
  .brand-mark{width:38px;height:38px;border-radius:10px}
  .brand h1{font-size:16px}
  .brand p{font-size:10px}
  .header-actions .btn-ghost{display:none}
  .btn{padding:8px 12px;min-height:36px}
  .mobile-tip{margin-bottom:10px}
  .editor-panel{border-radius:14px;padding:14px}
  .preview-wrap{border-radius:11px}
  .settings-grid{grid-template-columns:1fr 1fr}
}
@media(prefers-reduced-motion:reduce){
  *{scroll-behavior:auto!important;transition:none!important}
}