/* ================== Palette & base ================== */
:root{
  --bg: #061a2c;
  --text: #eaf2ff;
  --muted: #b6c9e6;

  --card-bg: rgba(255,255,255,.10);
  --card-stroke: rgba(255,255,255,.28);
  --card-shadow: 0 18px 50px rgba(0,0,0,.45);

  --primary-1: #22a2ff;
  --primary-2: #00d1ff;
  --primary-3: #1c7ed6; /* hover */

  --ring: rgba(53,183,255,.35);
  --field-bg: rgba(10,25,40,.35);
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family:system-ui, Segoe UI, Roboto, Arial, sans-serif;
  color:var(--text);
  background:var(--bg);
  -webkit-font-smoothing:antialiased;
}

/* ================ Background ================ */
.bg{
  min-height:100vh;
  background-image:url('../img/smart_iot_4k_bg.png'); /* đổi path theo nơi bạn để file */
  background-size:cover;       /* đảm bảo full màn hình, không méo */
  background-position:center;
  background-repeat:no-repeat;
}
.bg-overlay{
  position:absolute; inset:0;
  background:
    radial-gradient(1200px 600px at 18% 40%, rgba(4,14,24,.58), transparent 60%),
    linear-gradient(120deg, rgba(0,0,0,.25), rgba(0,0,0,.55));
  pointer-events:none;
}

/* ================ Layout ================ */
.login-wrap{
  position:relative;
  min-height:100vh;
  display:grid;
  place-items:center;
  padding:24px;
}

/* ================ Card (glass + neon border) ================ */
.login-card{
  position:relative;
  width:min(380px, 92vw);
  padding:26px 22px 24px;
  border-radius:18px;
  background:var(--card-bg);
  backdrop-filter: blur(12px) saturate(140%);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  border:1px solid var(--card-stroke);
  box-shadow: var(--card-shadow);
  overflow:hidden;
}

/* viền chuyển sắc siêu mảnh */
.login-card::before{
  content:"";
  position:absolute; inset:0; border-radius:18px;
  padding:1px;
  background: conic-gradient(
    from 220deg at 50% 50%,
    rgba(0,209,255,.0),
    rgba(0,209,255,.55),
    rgba(34,162,255,.75),
    rgba(0,209,255,.55),
    rgba(0,209,255,.0) 70%
  );

  /* CẮT RỖNG PHẦN GIỮA — chuẩn + webkit */
  /* Khai báo CHUẨN trước (để linter yên tâm) */
  mask:
    linear-gradient(#000 0 0) content-box,
    linear-gradient(#000 0 0);
  mask-composite: exclude;          /* Firefox/đặc tả */

  /* Khai báo cho WebKit (Chrome/Safari cũ) */
  -webkit-mask:
    linear-gradient(#000 0 0) content-box,
    linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;      /* tương đương exclude */

  pointer-events:none;
}

/* điểm sáng nhẹ góc trên/phải */
.card-decoration{
  position:absolute; right:-40px; top:-60px;
  width:220px; height:220px; border-radius:50%;
  background: radial-gradient(closest-side, rgba(0,209,255,.45), rgba(0,209,255,0));
  filter: blur(18px);
  pointer-events:none;
}
/* glow mờ phía dưới */
.card-glow{
  position:absolute; left:50%; bottom:-70px; transform:translateX(-50%);
  width:420px; height:160px;
  background: radial-gradient(closest-side, rgba(34,162,255,.25), rgba(34,162,255,0));
  filter: blur(20px);
  pointer-events:none;
}

.brand{ text-align:center; margin-bottom:12px; }
.brand img{ height:42px; margin-bottom:8px; }
.brand h2{ margin:0 0 6px; font-weight:800; letter-spacing:.3px; }
.brand .sub{ margin:0; color:var(--muted); font-size:13px; }

/* ================ Fields ================ */
.field{ margin-top:12px; }
.field input{
  width:100%;
  padding:12px 14px;
  border-radius:12px;
  border:1px solid rgba(255,255,255,.25);
  background:var(--field-bg);
  color:var(--text);
  outline:none;
  transition:border .15s ease, box-shadow .15s ease, background .15s ease;
}
.field input::placeholder{ color:rgba(234,244,255,.78); }
.field input:focus{
  border-color:#35b7ff;
  box-shadow: 0 0 0 4px var(--ring);
  background: rgba(10,25,40,.45);
}

/* ================ Button (gradient + sheen) ================ */
.btn-primary{
  position:relative;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  width:100%;
  margin-top:14px;
  padding:12px 14px;
  border:0;
  border-radius:12px;
  cursor:pointer;
  color:#fff;
  font-weight:800;
  letter-spacing:.2px;
  background: linear-gradient(135deg, var(--primary-1), var(--primary-2));
  box-shadow: 0 10px 26px rgba(0,186,255,.35), inset 0 0 0 1px rgba(255,255,255,.15);
  transition: transform .06s ease, filter .2s ease, box-shadow .2s ease;
  overflow:hidden;
}
.btn-primary:hover{
  filter:brightness(1.05);
  box-shadow: 0 14px 30px rgba(0,186,255,.45), inset 0 0 0 1px rgba(255,255,255,.18);
}
.btn-primary:active{ transform: translateY(1px); }

/* vệt sáng lướt */
.btn-primary .sheen{
  position:absolute; inset:-40% -20%;
  background: linear-gradient(115deg, rgba(255,255,255,.0) 30%, rgba(255,255,255,.35) 50%, rgba(255,255,255,.0) 70%);
  transform: translateX(-120%) rotate(8deg);
  transition: transform .7s ease;
  pointer-events:none;
}
.btn-primary:hover .sheen{ transform: translateX(30%) rotate(8deg); }

/* ================ Mobile ================ */
@media (max-width:480px){
  .login-card{ padding:22px 18px }
  .brand h2{ font-size:20px }
}