/* Login Page Styles */
:root {
    --primary-color: #0d9488;
    --primary-600: #0f766e;
    --bg-body: #eef2f6;
    --surface: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --border-color: #e2e8f0;
    --input-bg: #f8fafc;
    --input-border: #e2e8f0;
    --input-focus: rgba(13,148,136,0.18);
    --error-color: #ef4444;
}
html[data-theme="dark"] {
    --bg-body: #0b1220;
    --surface: #0f172a;
    --text-primary: #e2e8f0;
    --text-secondary: #cbd5e1;
    --border-color: #1f2a44;
    --input-bg: #0b1324;
    --input-border: #1f2a44;
    --input-focus: rgba(52,211,153,0.18);
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Segoe UI', Arial, sans-serif; background: var(--bg-body); color: var(--text-primary); min-height: 100vh; display: flex; align-items: center; justify-content: center; padding: 1rem; }

/* Topbar */
.login-topbar { position: fixed; top: 0; left: 0; right: 0; display: flex; align-items: center; justify-content: space-between; padding: .6rem .8rem; background: var(--surface); border-bottom: 1px solid var(--border-color); z-index: 5; }
.back-link { color: var(--text-primary); text-decoration: none; display: inline-flex; align-items: center; gap: .5rem; padding: .45rem .7rem; border: 1px solid var(--border-color); border-radius: .55rem; background: var(--surface); }
.back-link i { color: var(--text-secondary); }
.theme-btn { border: 1px solid var(--border-color); background: var(--surface); color: var(--text-secondary); padding: .45rem .6rem; border-radius: .55rem; cursor: pointer; }
.theme-btn i { color: var(--text-secondary); }

/* Card */
.login-card { background: var(--surface); padding: clamp(1.2rem, 3vw, 2rem); border-radius: 1rem; border: 1px solid var(--border-color); box-shadow: 0 4px 20px rgba(15,23,42,.06); width: min(98%, 520px); margin-top: 4.5rem; }
.logo { display: block; text-align: center; font-size: clamp(1.6rem, 4.5vw, 2rem); font-weight: 800; margin-bottom: .75rem; color: var(--primary-600); letter-spacing: 1px; }
.admin-login-title { text-align: center; font-size: clamp(1.2rem, 4vw, 1.4rem); color: var(--text-secondary); margin-bottom: 1rem; font-weight: 800; }
.error-message { background: rgba(239,68,68,0.08); color: var(--error-color); padding: .6rem .75rem; border-radius: .6rem; border: 1px solid rgba(239,68,68,0.25); font-size: .95rem; margin-bottom: .9rem; text-align: center; }

.form-group { margin-bottom: .9rem; }
.form-group label { display: block; margin-bottom: .4rem; font-size: .95rem; color: var(--text-secondary); font-weight: 700; }
.form-group input { width: 100%; padding: .85rem .9rem; background: var(--input-bg); border: 1px solid var(--input-border); border-radius: .6rem; color: var(--text-primary); font-size: 1rem; }
.form-group input:focus { outline: none; border-color: var(--primary-color); box-shadow: 0 0 0 3px var(--input-focus); }

.btn { width: 100%; padding: .9rem 1rem; background: var(--primary-color); color: #fff; border: none; border-radius: .6rem; font-size: 1rem; font-weight: 800; cursor: pointer; transition: transform .15s ease, background .15s ease; margin-top: .2rem; }
.btn:hover { background: var(--primary-600); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

/* Responsive */
@media (max-width: 600px) { body { padding: .6rem; } .login-card { margin-top: 3.6rem; } }
@media (max-width: 400px) { .login-card { padding: 1rem; border-radius: .8rem; } .logo { font-size: 1.5rem; } .admin-login-title { font-size: 1.1rem; } }