:root {
    --bg: #f4f6f8;
    --surface: #ffffff;
    --surface-soft: #f9fbfc;
    --line: #dce3ea;
    --text: #16202a;
    --muted: #667483;
    --primary: #176b5b;
    --primary-dark: #0f4e43;
    --accent: #d89a24;
    --danger: #bc3c3c;
    --info: #2f6f9f;
    --shadow: 0 18px 42px rgba(22, 32, 42, .08);
}

* { box-sizing: border-box; }

body {
    min-height: 100vh;
    margin: 0;
    color: var(--text);
    background: var(--bg);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a { color: inherit; text-decoration: none; }

.btn-primary {
    --bs-btn-bg: var(--primary);
    --bs-btn-border-color: var(--primary);
    --bs-btn-hover-bg: var(--primary-dark);
    --bs-btn-hover-border-color: var(--primary-dark);
    font-weight: 800;
}

.btn-outline-primary {
    --bs-btn-color: var(--primary);
    --bs-btn-border-color: var(--primary);
    --bs-btn-hover-bg: var(--primary);
    --bs-btn-hover-border-color: var(--primary);
    font-weight: 800;
}

.app-sidebar {
    position: fixed;
    left: 0;
    top: 64px;
    bottom: 0;
    width: 240px;
    padding: 14px;
    overflow-y: auto;
    background: #111b22;
    color: #eaf0f4;
    z-index: 10;
}

.side-nav {
    display: grid;
    gap: 6px;
}

.side-nav a {
    display: flex;
    align-items: center;
    gap: 11px;
    min-height: 42px;
    padding: 10px 12px;
    border-radius: 8px;
    color: #b9c7d1;
    font-weight: 700;
}

.side-nav a:hover {
    color: #fff;
    background: rgba(255,255,255,.1);
}

.has-sidebar {
    margin-left: 240px;
}

.login-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 20px;
}

.login-card {
    width: min(100%, 430px);
    padding: 24px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 8px;
    box-shadow: var(--shadow);
}

@media (max-width: 900px) {
    .app-sidebar {
        position: static;
        width: auto;
    }

    .has-sidebar {
        margin-left: 0;
    }
}