/*
Theme Name: English Free Course
Theme URI: https://example.com/
Author: Lab
Description: Giao diện WordPress đơn giản cho website khóa học tiếng Anh miễn phí.
Version: 1.0
*/
:root{--primary:#2563eb;--dark:#0f172a;--muted:#64748b;--bg:#f8fafc;--white:#fff}
*{box-sizing:border-box}body{margin:0;font-family:Arial,Helvetica,sans-serif;color:var(--dark);background:var(--bg);line-height:1.6}
a{color:inherit;text-decoration:none}.container{width:min(1100px,92%);margin:auto}
.site-header{background:#fff;border-bottom:1px solid #e2e8f0}.header-inner{display:flex;align-items:center;justify-content:space-between;padding:18px 0}
.logo{font-size:22px;font-weight:800;color:var(--primary)}nav a{margin-left:22px;font-weight:600}
.hero{padding:80px 0;background:linear-gradient(135deg,#eff6ff,#fff)}.hero h1{font-size:46px;line-height:1.15;margin:0 0 18px}.hero p{font-size:19px;color:var(--muted);max-width:650px}.btn{display:inline-block;background:var(--primary);color:#fff;padding:12px 20px;border-radius:8px;font-weight:700;margin-top:15px}
.section{padding:55px 0}.section h2{text-align:center;font-size:32px;margin:0 0 35px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}
.card{background:#fff;border:1px solid #e2e8f0;border-radius:12px;padding:25px;box-shadow:0 4px 16px rgba(15,23,42,.05)}.card h3{margin-top:0}.card p{color:var(--muted)}
.level{display:inline-block;background:#dbeafe;color:#1d4ed8;padding:4px 9px;border-radius:999px;font-size:13px;font-weight:700}
.footer{background:var(--dark);color:#cbd5e1;padding:30px 0;margin-top:30px}.footer p{margin:0}
@media(max-width:750px){.grid{grid-template-columns:1fr}.hero h1{font-size:36px}nav a{margin-left:10px;font-size:14px}}

.upload-section{background:#fff}.upload-card{max-width:850px;margin:auto;background:#f8fafc;border:1px solid #e2e8f0;border-radius:12px;padding:28px}.upload-intro{text-align:center;color:var(--muted);margin-top:0}.upload-warning{text-align:center;color:#b45309;background:#fffbeb;border:1px solid #fde68a;padding:12px;border-radius:8px}