/* MailSandbox — smtp.dev inspired dark UI */
:root {
  --bg: #0a0a0a;
  --bg-elevated: #111111;
  --bg-hover: #1a1a1a;
  --border: #262626;
  --text: #fafafa;
  --text-muted: #a3a3a3;
  --accent: #22c55e;
  --accent-hover: #16a34a;
  --danger: #ef4444;
  --warning: #f59e0b;
  --radius: 8px;
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;
  --mono: ui-monospace, "Cascadia Code", "SF Mono", monospace;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; background: var(--bg); color: var(--text); font-family: var(--font); line-height: 1.5; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); }

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.container-narrow { max-width: 480px; margin: 0 auto; padding: 0 24px; }

/* Nav */
.topnav { border-bottom: 1px solid var(--border); background: rgba(10,10,10,.85); backdrop-filter: blur(12px); position: sticky; top: 0; z-index: 50; }
.topnav-inner { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.topnav-split { display: flex; align-items: stretch; height: 56px; }
.topnav-brand { width: 240px; flex-shrink: 0; display: flex; align-items: center; gap: 8px; padding: 0 24px; border-right: 1px solid var(--border); }
.topnav-actions { flex: 1; display: flex; align-items: center; justify-content: flex-end; padding: 0 24px; }
.topnav-badge { color: var(--warning); font-size: .7rem; font-weight: 600; letter-spacing: .06em; text-transform: uppercase; }
.brand { font-weight: 700; font-size: 1.1rem; color: var(--text); letter-spacing: -.02em; }
.brand:hover { color: var(--text); }
.brand span { color: var(--accent); }
.brand-with-logo { display: inline-flex; align-items: center; gap: 10px; }
.brand-with-logo img { display: block; height: 28px; width: auto; flex-shrink: 0; }
.brand-text { white-space: nowrap; }
.nav-links { display: flex; gap: 20px; align-items: center; }
.nav-links a { color: var(--text-muted); font-size: .9rem; }
.nav-links a:hover { color: var(--text); }

/* Buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 8px 16px; border-radius: var(--radius); font-size: .875rem; font-weight: 500; border: 1px solid transparent; cursor: pointer; transition: .15s; }
.btn-primary { background: var(--accent); color: #000; }
.btn-primary:hover { background: var(--accent-hover); color: #000; }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--border); }
.btn-ghost:hover { background: var(--bg-hover); }
.btn-danger { background: transparent; color: var(--danger); border-color: var(--danger); }
.btn-sm { padding: 4px 10px; font-size: .8rem; }

/* Forms */
.form-group { margin-bottom: 16px; }
label { display: block; font-size: .85rem; color: var(--text-muted); margin-bottom: 6px; }
input, select, textarea {
  width: 100%; padding: 10px 12px; background: var(--bg-elevated); border: 1px solid var(--border);
  border-radius: var(--radius); color: var(--text); font-size: .9rem;
}
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--accent); }

/* Cards */
.card { background: var(--bg-elevated); border: 1px solid var(--border); border-radius: 12px; padding: 24px; }
.card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.card-title { font-size: 1.1rem; font-weight: 600; margin: 0; }

/* Layout app */
.app-shell { display: flex; min-height: calc(100vh - 56px); }
.sidebar { width: 240px; border-right: 1px solid var(--border); padding: 20px 12px; flex-shrink: 0; }
.sidebar a { display: flex; align-items: center; gap: 10px; padding: 8px 12px; border-radius: var(--radius); color: var(--text-muted); font-size: .875rem; margin-bottom: 2px; }
.sidebar a:hover, .sidebar a.active { background: var(--bg-hover); color: var(--text); }
.sidebar a.active { border-left: 2px solid var(--accent); }
.main { flex: 1; padding: 32px; overflow: auto; }

/* Tables */
.table { width: 100%; border-collapse: collapse; font-size: .875rem; }
.table th, .table td { text-align: left; padding: 12px; border-bottom: 1px solid var(--border); }
.table th { color: var(--text-muted); font-weight: 500; font-size: .8rem; text-transform: uppercase; letter-spacing: .04em; }
.table tr:hover td { background: var(--bg-hover); }
.badge { display: inline-block; padding: 2px 8px; border-radius: 999px; font-size: .75rem; font-weight: 500; }
.badge-success { background: rgba(34,197,94,.15); color: var(--accent); }
.badge-muted { background: var(--bg-hover); color: var(--text-muted); }
.badge-warning { background: rgba(245,158,11,.15); color: var(--warning); }

/* Alerts */
.alert { padding: 12px 16px; border-radius: var(--radius); margin-bottom: 16px; font-size: .875rem; }
.alert-success { background: rgba(34,197,94,.1); border: 1px solid rgba(34,197,94,.3); color: var(--accent); }
.alert-error { background: rgba(239,68,68,.1); border: 1px solid rgba(239,68,68,.3); color: var(--danger); }
.alert-info { background: rgba(59,130,246,.1); border: 1px solid rgba(59,130,246,.3); color: #60a5fa; }

/* Landing */
.hero { padding: 80px 0 100px; text-align: center; }
.hero h1 { font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 700; letter-spacing: -.03em; line-height: 1.1; margin: 0 0 20px; }
.hero p { font-size: 1.15rem; color: var(--text-muted); max-width: 560px; margin: 0 auto 32px; }
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; padding: 60px 0; }
.feature-card h3 { margin: 0 0 8px; font-size: 1rem; }
.feature-card p { margin: 0; color: var(--text-muted); font-size: .875rem; }

/* Mail */
.mail-layout { display: grid; grid-template-columns: 280px 1fr; gap: 0; min-height: calc(100vh - 56px); }
.mail-list { border-right: 1px solid var(--border); overflow-y: auto; }
.mail-item { padding: 14px 16px; border-bottom: 1px solid var(--border); cursor: pointer; }
.mail-item:hover { background: var(--bg-hover); }
.mail-item.unread { border-left: 2px solid var(--accent); }
.mail-item .subject { font-weight: 500; margin-bottom: 4px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.mail-item .meta { font-size: .8rem; color: var(--text-muted); }
.mail-view { padding: 24px; overflow-y: auto; }
.mail-view iframe { width: 100%; min-height: 400px; border: 1px solid var(--border); border-radius: var(--radius); background: #fff; }
.otp-badge { font-family: var(--mono); font-size: 1.2rem; background: rgba(34,197,94,.15); color: var(--accent); padding: 8px 16px; border-radius: var(--radius); display: inline-block; }

/* Stats */
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; margin-bottom: 32px; }
.stat-card { background: var(--bg-elevated); border: 1px solid var(--border); border-radius: 12px; padding: 20px; }
.stat-card .value { font-size: 2rem; font-weight: 700; }
.stat-card .label { color: var(--text-muted); font-size: .85rem; }

/* Code */
code, pre { font-family: var(--mono); font-size: .85rem; }
pre { background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; overflow-x: auto; }
.mono { font-family: var(--mono); font-size: .85rem; }

@media (max-width: 768px) {
  .app-shell { flex-direction: column; }
  .sidebar { width: 100%; border-right: none; border-bottom: 1px solid var(--border); }
  .mail-layout { grid-template-columns: 1fr; }
}