*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --bg: #0f1117;
    --surface: #1a1d27;
    --surface2: #242836;
    --border: #2e3345;
    --text: #e1e4ed;
    --muted: #8b90a0;
    --primary: #6c5ce7;
    --primary-hover: #7c6ff7;
    --success: #00b894;
    --danger: #e74c3c;
    --danger-hover: #c0392b;
    --radius: 8px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

/* Nav */
nav {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    height: 56px;
    position: sticky;
    top: 0;
    z-index: 100;
}
.nav-brand {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: -0.5px;
}
.nav-links { display: flex; gap: 0.25rem; }
.nav-links a {
    color: var(--muted);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    font-size: 0.9rem;
    transition: all 0.15s;
}
.nav-links a:hover { color: var(--text); background: var(--surface2); }
.nav-links a.active { color: var(--primary); background: var(--surface2); }

/* Layout */
main { max-width: 800px; margin: 2rem auto; padding: 0 1.5rem; }
h1 { font-size: 1.5rem; margin-bottom: 1.5rem; font-weight: 600; }

/* Cards */
.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

/* Forms */
label {
    display: block;
    font-size: 0.85rem;
    color: var(--muted);
    margin-bottom: 0.35rem;
    font-weight: 500;
}
input, select, textarea {
    width: 100%;
    padding: 0.6rem 0.8rem;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text);
    font-size: 0.95rem;
    font-family: inherit;
    transition: border-color 0.15s;
}
input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
}
textarea { resize: vertical; min-height: 100px; }
.form-row { margin-bottom: 1rem; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.6rem 1.2rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.9rem;
    font-family: inherit;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s;
    text-decoration: none;
    color: #fff;
}
.btn-primary { background: var(--primary); }
.btn-primary:hover { background: var(--primary-hover); }
.btn-danger { background: var(--danger); }
.btn-danger:hover { background: var(--danger-hover); }
.btn-sm { padding: 0.35rem 0.7rem; font-size: 0.8rem; }
.btn-outline {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text);
}
.btn-outline:hover { border-color: var(--muted); }

.btn-group { display: flex; gap: 0.5rem; margin-top: 1rem; }

/* Alert */
.alert {
    padding: 0.75rem 1rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
}
.alert-success { background: rgba(0,184,148,0.15); color: var(--success); border: 1px solid rgba(0,184,148,0.3); }
.alert-error { background: rgba(231,76,60,0.15); color: var(--danger); border: 1px solid rgba(231,76,60,0.3); }

/* Table */
table { width: 100%; border-collapse: collapse; }
th, td {
    text-align: left;
    padding: 0.65rem 0.8rem;
    border-bottom: 1px solid var(--border);
    font-size: 0.9rem;
}
th { color: var(--muted); font-weight: 500; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.5px; }
tr:last-child td { border-bottom: none; }
tr:hover td { background: rgba(255,255,255,0.02); }

/* Badges */
.badge {
    display: inline-block;
    padding: 0.15rem 0.5rem;
    border-radius: 99px;
    font-size: 0.75rem;
    font-weight: 600;
}
.badge-sent { background: rgba(0,184,148,0.15); color: var(--success); }
.badge-failed { background: rgba(231,76,60,0.15); color: var(--danger); }

/* Char counter */
.char-count { text-align: right; font-size: 0.8rem; color: var(--muted); margin-top: 0.25rem; }
.char-count.over { color: var(--danger); }

/* Empty state */
.empty { text-align: center; color: var(--muted); padding: 3rem 1rem; font-size: 0.95rem; }

/* Responsive */
@media (max-width: 600px) {
    nav { padding: 0 1rem; }
    .nav-links a { padding: 0.5rem 0.6rem; font-size: 0.8rem; }
    main { padding: 0 1rem; }
    .form-grid { grid-template-columns: 1fr; }
    th, td { padding: 0.5rem; font-size: 0.8rem; }
}