/* ── Reset & Variables ─────────────────────────────────── */
:root {
  --blue:      #2563eb;
  --indigo:    #4f46e5;
  --purple:    #7c3aed;
  --grad:      linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
  --grad-soft: linear-gradient(135deg, #eff6ff 0%, #f5f3ff 100%);
  --success:   #10b981;
  --warn:      #f59e0b;
  --danger:    #ef4444;
  --bg:        #f0f4ff;
  --card:      #ffffff;
  --text:      #0f172a;
  --muted:     #64748b;
  --border:    #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
  --shadow:    0 4px 20px rgba(37,99,235,.10);
  --shadow-lg: 0 12px 40px rgba(37,99,235,.18);
  --radius:    16px;
  --radius-sm: 10px;
  --radius-xs: 6px;
  --nav-h:     60px;
  --bot-h:     64px; /* mobile bottom nav */
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,'PingFang SC','Helvetica Neue','Microsoft YaHei',sans-serif;
  background:var(--bg);color:var(--text);min-height:100vh;font-size:14px;
  -webkit-font-smoothing:antialiased;
}
a{text-decoration:none;color:inherit}
button{font-family:inherit}
img,canvas{display:block}

/* ── Scrollbar ─────────────────────────────────────────── */
::-webkit-scrollbar{width:6px;height:6px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:#c7d2fe;border-radius:3px}

/* ── Topbar ────────────────────────────────────────────── */
.topbar{
  background:var(--grad);
  height:var(--nav-h);
  display:flex;align-items:center;
  padding:0 28px;gap:32px;
  box-shadow:0 2px 16px rgba(37,99,235,.3);
  position:sticky;top:0;z-index:200;
}
.logo{
  color:#fff;font-size:17px;font-weight:800;letter-spacing:.5px;
  display:flex;align-items:center;gap:8px;white-space:nowrap;
}
.logo-icon{font-size:22px;line-height:1}
.nav{display:flex;gap:2px;flex:1;overflow-x:auto}
.nav::-webkit-scrollbar{display:none}
.nav a{
  color:rgba(255,255,255,.8);padding:7px 14px;border-radius:8px;
  font-size:13.5px;font-weight:500;white-space:nowrap;transition:.18s;
}
.nav a:hover,.nav a.on{background:rgba(255,255,255,.18);color:#fff}

/* ── Page wrapper ──────────────────────────────────────── */
.wrap{max-width:1000px;margin:0 auto;padding:36px 20px 100px}

/* ── Section heading ───────────────────────────────────── */
.pg-title{
  text-align:center;font-size:24px;font-weight:800;color:var(--text);margin-bottom:6px;
}
.pg-sub{text-align:center;font-size:13px;color:var(--muted);margin-bottom:32px}

/* ── Card ──────────────────────────────────────────────── */
.card{
  background:var(--card);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:28px;margin-bottom:18px;
}
.card-hd{
  font-size:15px;font-weight:700;color:var(--text);
  margin-bottom:20px;display:flex;align-items:center;gap:8px;
}
.card-hd::before{
  content:'';width:4px;height:16px;border-radius:2px;
  background:var(--grad);flex-shrink:0;
}

/* ── Upload Zone ───────────────────────────────────────── */
.drop{
  border:2px dashed var(--border);border-radius:14px;
  padding:56px 20px;text-align:center;cursor:pointer;
  background:linear-gradient(135deg,#f8faff 0%,#f5f3ff 100%);
  transition:.2s;position:relative;overflow:hidden;
}
.drop::before{
  content:'';position:absolute;inset:0;
  background:radial-gradient(circle at 50% 0%,rgba(79,70,229,.06) 0%,transparent 65%);
  pointer-events:none;
}
.drop:hover,.drop.over{border-color:var(--blue);background:linear-gradient(135deg,#eff6ff,#ede9fe)}
.drop input[type=file]{position:absolute;inset:0;opacity:0;cursor:pointer;width:100%;height:100%}
.drop-icon{font-size:44px;line-height:1;margin-bottom:12px;filter:drop-shadow(0 4px 8px rgba(79,70,229,.2))}
.drop p{font-size:15px;color:var(--muted);margin-bottom:3px}
.drop p.hint{font-size:12px;color:#94a3b8}

/* ── Buttons ───────────────────────────────────────────── */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  padding:10px 26px;border-radius:var(--radius-sm);font-size:14px;font-weight:600;
  border:none;cursor:pointer;transition:.18s;white-space:nowrap;
}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 4px 14px rgba(37,99,235,.35)}
.btn-primary:hover{opacity:.92;transform:translateY(-1px);box-shadow:0 6px 18px rgba(37,99,235,.45)}
.btn-green{background:var(--success);color:#fff;box-shadow:0 4px 14px rgba(16,185,129,.3)}
.btn-green:hover{opacity:.92;transform:translateY(-1px)}
.btn-ghost{background:#f1f5f9;color:var(--muted);border:1.5px solid var(--border)}
.btn-ghost:hover{border-color:var(--blue);color:var(--blue);background:#eff6ff}
.btn-lg{padding:13px 36px;font-size:15px;border-radius:12px}
.btn-block{width:100%;justify-content:center}
.btn:disabled{opacity:.45;cursor:not-allowed;transform:none!important}

/* ── Steps bar ─────────────────────────────────────────── */
.steps{display:flex;align-items:center;justify-content:center;gap:0;margin-bottom:32px}
.step{
  display:flex;flex-direction:column;align-items:center;gap:6px;
  min-width:80px;position:relative;
}
.step+.step::before{
  content:'';position:absolute;top:14px;right:calc(50% + 16px);
  width:calc(100% - 32px);height:2px;background:var(--border);
}
.step-dot{
  width:28px;height:28px;border-radius:50%;border:2px solid var(--border);
  background:#fff;display:flex;align-items:center;justify-content:center;
  font-size:12px;font-weight:700;color:var(--muted);z-index:1;
}
.step.done .step-dot{background:var(--grad);border-color:transparent;color:#fff}
.step.active .step-dot{background:var(--grad);border-color:transparent;color:#fff;
  box-shadow:0 0 0 4px rgba(79,70,229,.2)}
.step-label{font-size:12px;color:var(--muted);font-weight:500}
.step.active .step-label,.step.done .step-label{color:var(--blue)}

/* ── Color swatches ────────────────────────────────────── */
.colors{display:flex;gap:8px;flex-wrap:wrap;align-items:flex-start;margin-bottom:14px}
.swatch-wrap{display:flex;flex-direction:column;align-items:center;gap:4px;cursor:pointer}
.swatch{
  width:36px;height:36px;border-radius:9px;cursor:pointer;
  border:2.5px solid transparent;transition:.15s;position:relative;flex-shrink:0;
}
.swatch:hover{transform:scale(1.1)}
.swatch.on{border-color:var(--blue);box-shadow:0 0 0 3px rgba(37,99,235,.25)}
.swatch.white{border-color:var(--border)}
.swatch.on.white{border-color:var(--blue)}
.swatch .tick{
  position:absolute;inset:0;display:none;align-items:center;justify-content:center;
  color:#fff;font-size:14px;text-shadow:0 1px 3px rgba(0,0,0,.5);
}
.swatch.on .tick{display:flex}
.swatch.white .tick{color:#1d4ed8}
.swatch-label{font-size:10px;color:var(--muted);white-space:nowrap;max-width:40px;text-align:center;line-height:1.2}
.color-row{display:flex;align-items:center;gap:10px;margin-top:8px}
.color-row label{font-size:13px;color:var(--muted);white-space:nowrap}
input[type=color]{
  width:38px;height:38px;padding:3px;border:1.5px solid var(--border);
  border-radius:10px;cursor:pointer;background:#fff;
}
.hex-input{
  font-family:'SFMono-Regular',Consolas,monospace;font-size:13px;
  padding:8px 12px;border:1.5px solid var(--border);border-radius:8px;
  width:88px;color:var(--text);
}
.hex-input:focus{outline:none;border-color:var(--blue)}

/* ── Preview split ─────────────────────────────────────── */
.split{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:20px}
.pbox{text-align:center}
.pbox-lbl{font-size:12px;color:var(--muted);margin-bottom:8px;font-weight:600}
.pbox canvas,.pbox img{
  max-width:100%;max-height:320px;border-radius:12px;
  border:1px solid var(--border);object-fit:contain;
  /* checkerboard for transparent */
  background:repeating-conic-gradient(#e2e8f0 0% 25%,#fff 0% 50%) 0 0/16px 16px;
}
.pbox img.solid{background:#f8faff}

/* ── Loading spinner ───────────────────────────────────── */
.loader{display:flex;flex-direction:column;align-items:center;gap:16px;padding:48px 20px}
.spin{
  width:44px;height:44px;border:3px solid var(--border);
  border-top-color:var(--blue);border-radius:50%;
  animation:spin .75s linear infinite;
}
@keyframes spin{to{transform:rotate(360deg)}}
.loader p{color:var(--muted);font-size:14px}

/* ── Sizes grid ────────────────────────────────────────── */
.size-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(90px,1fr));gap:8px;margin-bottom:20px}
.size-item{
  border:1.5px solid var(--border);border-radius:10px;padding:10px 6px;
  text-align:center;cursor:pointer;transition:.15s;background:#fafbff;
}
.size-item:hover{border-color:var(--blue);background:#eff6ff}
.size-item.on{border-color:var(--blue);background:#eff6ff;color:var(--blue)}
.size-nm{font-size:12px;font-weight:700}
.size-mm{font-size:11px;color:var(--muted);margin-top:2px}
.size-item.on .size-mm{color:#93c5fd}

/* ── Form controls ─────────────────────────────────────── */
.row2{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:16px}
.row3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:16px;margin-bottom:16px}
.fg{display:flex;flex-direction:column;gap:6px}
.fg label{font-size:12px;font-weight:600;color:var(--muted)}
.sel{
  padding:10px 12px;border:1.5px solid var(--border);border-radius:var(--radius-xs);
  font-size:13px;color:var(--text);background:#fff;cursor:pointer;appearance:none;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%2364748b' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat:no-repeat;background-position:right 10px center;padding-right:30px;
}
.sel:focus{outline:none;border-color:var(--blue)}
.inp{
  padding:10px 12px;border:1.5px solid var(--border);border-radius:var(--radius-xs);
  font-size:13px;color:var(--text);background:#fff;
}
.inp:focus{outline:none;border-color:var(--blue)}

/* ── Range slider ──────────────────────────────────────── */
.slider-row{display:flex;align-items:center;gap:12px}
input[type=range]{
  flex:1;-webkit-appearance:none;height:4px;
  background:linear-gradient(to right,var(--blue) 0%,var(--blue) var(--pct,50%),var(--border) var(--pct,50%),var(--border) 100%);
  border-radius:2px;outline:none;cursor:pointer;
}
input[type=range]::-webkit-slider-thumb{
  -webkit-appearance:none;width:18px;height:18px;
  background:var(--grad);border-radius:50%;cursor:pointer;
  box-shadow:0 2px 6px rgba(37,99,235,.4);
}
.slider-val{font-size:13px;font-weight:700;color:var(--blue);min-width:36px;text-align:right}

/* ── Stats ─────────────────────────────────────────────── */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:20px}
.stat{background:linear-gradient(135deg,#f8faff,#f5f3ff);border-radius:12px;padding:14px;text-align:center;border:1px solid rgba(79,70,229,.1)}
.stat-v{font-size:20px;font-weight:800;background:var(--grad);-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.stat-l{font-size:11px;color:var(--muted);margin-top:3px}

/* ── Print preview ─────────────────────────────────────── */
.print-bg{background:#d1d5db;border-radius:14px;padding:24px;display:flex;justify-content:center;align-items:center;min-height:280px;margin-bottom:16px}
#printCanvas{box-shadow:0 4px 20px rgba(0,0,0,.15);border-radius:2px}

/* ── Cropper ───────────────────────────────────────────── */
.cropper-box{background:#0f172a;border-radius:14px;overflow:hidden;max-height:440px}
.cropper-box img{max-width:100%;display:block}

/* ── Error box ─────────────────────────────────────────── */
.errbox{background:#fef2f2;border:1.5px solid #fecaca;border-radius:12px;padding:20px;text-align:center}
.errbox p{color:#dc2626;font-size:14px;margin-bottom:12px}

/* ── Action bar ────────────────────────────────────────── */
.act-bar{display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.act-bar .spacer{flex:1}

/* ── Homepage hero ─────────────────────────────────────── */
.hero{
  background:var(--grad);border-radius:24px;padding:56px 40px 48px;
  margin-bottom:32px;position:relative;overflow:hidden;text-align:center;
}
.hero::before{
  content:'';position:absolute;inset:0;pointer-events:none;
  background:
    url("data:image/svg+xml,%3Csvg width='860' height='320' xmlns='http://www.w3.org/2000/svg'%3E%3Ccircle cx='720' cy='50' r='220' fill='rgba(255,255,255,.07)'/%3E%3Ccircle cx='60' cy='280' r='160' fill='rgba(255,255,255,.05)'/%3E%3Ccircle cx='420' cy='340' r='120' fill='rgba(255,255,255,.04)'/%3E%3C/svg%3E") no-repeat center;
}
.hero::after{
  content:'';position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(ellipse 60% 50% at 80% 20%,rgba(255,255,255,.08) 0%,transparent 70%);
}
.hero h1{font-size:38px;font-weight:900;color:#fff;margin-bottom:10px;position:relative;z-index:1;
  letter-spacing:-.5px;text-shadow:0 2px 16px rgba(0,0,0,.15)}
.hero p{font-size:16px;color:rgba(255,255,255,.88);margin-bottom:24px;position:relative;z-index:1}
.hero-tags{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;margin-bottom:28px;position:relative;z-index:1}
.hero-tag{
  background:rgba(255,255,255,.15);backdrop-filter:blur(8px);
  border:1px solid rgba(255,255,255,.25);border-radius:20px;
  font-size:12px;font-weight:600;color:#fff;padding:4px 12px;
}
.hero .hero-btns{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;position:relative;z-index:1}
.btn-white{background:#fff;color:var(--blue);font-weight:700;box-shadow:0 4px 20px rgba(0,0,0,.18)}
.btn-white:hover{transform:translateY(-2px);box-shadow:0 8px 28px rgba(0,0,0,.22)}
.btn-outline-white{background:rgba(255,255,255,.12);backdrop-filter:blur(8px);border:1.5px solid rgba(255,255,255,.55);color:#fff}
.btn-outline-white:hover{background:rgba(255,255,255,.22);border-color:#fff}

/* ── Tool cards (homepage) ─────────────────────────────── */
.tools{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-bottom:40px}
.tc{
  background:var(--card);border-radius:var(--radius);padding:24px 20px 22px;
  box-shadow:var(--shadow);cursor:pointer;transition:.22s;
  border:1.5px solid transparent;text-align:center;
  display:flex;flex-direction:column;align-items:center;gap:10px;
}
.tc:hover{transform:translateY(-5px);box-shadow:var(--shadow-lg);border-color:rgba(37,99,235,.15)}
.tc-icon{
  width:64px;height:64px;border-radius:18px;display:flex;align-items:center;
  justify-content:center;font-size:30px;margin-bottom:4px;
  box-shadow:0 4px 12px rgba(0,0,0,.06);
  transition:transform .22s;
}
.tc:hover .tc-icon{transform:scale(1.08)}
.tc-name{font-size:14px;font-weight:700;color:var(--text)}
.tc-desc{font-size:12px;color:var(--muted);line-height:1.5}
.tc-badge{
  font-size:10px;font-weight:700;padding:2px 8px;border-radius:20px;
  background:#fef3c7;color:#d97706;margin-top:2px;
}

/* ── Mobile bottom nav ─────────────────────────────────── */
.bot-nav{
  display:none;position:fixed;bottom:0;left:0;right:0;height:var(--bot-h);z-index:300;
  background:rgba(255,255,255,.95);backdrop-filter:blur(16px);
  border-top:1px solid var(--border);
  box-shadow:0 -4px 20px rgba(0,0,0,.08);
}
.bot-nav ul{display:flex;height:100%;list-style:none}
.bot-nav li{flex:1}
.bot-nav a{
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  height:100%;gap:3px;color:var(--muted);font-size:10px;font-weight:500;transition:.15s;
}
.bot-nav a .bicon{font-size:20px;line-height:1}
.bot-nav a.on{color:var(--blue)}
.bot-nav a.on .bicon{filter:drop-shadow(0 2px 4px rgba(37,99,235,.4))}

/* ── Model Selector ────────────────────────────────────── */
.model-selector{display:flex;gap:10px;flex-wrap:wrap}
.model-opt{
  display:flex;align-items:center;gap:10px;
  padding:11px 14px;border-radius:12px;cursor:pointer;
  border:2px solid var(--border);background:#fff;
  transition:border-color .2s,background .2s,opacity .2s;
  flex:1;min-width:130px;position:relative;
  user-select:none;
}
.model-opt input{display:none}
.model-opt.on{border-color:var(--blue);background:#eff6ff}
.model-opt.loading{opacity:.6;cursor:default}
.model-icon{font-size:22px;flex-shrink:0}
.model-info{display:flex;flex-direction:column;gap:2px;min-width:0}
.model-label{font-size:14px;font-weight:600;color:var(--text)}
.model-sub{font-size:11px;color:var(--muted);white-space:nowrap}
.model-slow-tag{
  position:absolute;top:6px;right:8px;
  background:#fef3c7;color:#d97706;
  font-size:10px;font-weight:700;padding:2px 7px;border-radius:6px;
}
/* animated loading dot */
.model-loading-dot{
  position:absolute;top:6px;right:8px;
  width:8px;height:8px;border-radius:50%;
  background:var(--blue);opacity:.5;
  animation:mdot .9s ease-in-out infinite alternate;
}
@keyframes mdot{to{opacity:1;transform:scale(1.3)}}

/* ── Responsive ────────────────────────────────────────── */
@media(max-width:768px){
  .topbar{padding:0 16px;gap:12px}
  .nav{display:none} /* hide desktop nav on mobile */
  .bot-nav{display:flex}
  .wrap{padding:20px 14px 80px}
  .hero{padding:36px 20px 32px;border-radius:18px}
  .hero h1{font-size:26px}
  .hero p{font-size:14px}
  .split{grid-template-columns:1fr}
  .row2{grid-template-columns:1fr}
  .row3{grid-template-columns:1fr 1fr}
  .stats{grid-template-columns:1fr 1fr}
  .card{padding:18px}
  .tools{grid-template-columns:repeat(2,1fr)}
  .hero-tag{font-size:11px;padding:3px 10px}
  .tc{padding:18px 14px}
  .tc-icon{width:50px;height:50px;font-size:24px}
}
@media(max-width:380px){
  .tools{grid-template-columns:1fr 1fr}
  .row3{grid-template-columns:1fr}
}