/* ============ Reset & Base ============ */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --bg: #0f172a;
    --bg-card: #1e293b;
    --bg-elevated: #334155;
    --border: #334155;
    --border-strong: #475569;
    --text: #e2e8f0;
    --text-muted: #94a3b8;
    --text-subtle: #64748b;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --success: #10b981;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --warning: #f59e0b;
    --radius: 8px;
    --radius-lg: 12px;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.5);
    /* --- Tech-feel additions --- */
    --accent: #22d3ee;          /* electric cyan accent */
    --accent-glow: rgba(34, 211, 238, 0.35);
    --primary-glow: rgba(59, 130, 246, 0.4);
    --font-display: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', Consolas, monospace;
    --ease: cubic-bezier(0.22, 1, 0.36, 1);   /* smooth techy ease-out */
    --ease-snap: cubic-bezier(0.34, 1.56, 0.64, 1); /* subtle overshoot */
}

body {
    font-family: var(--font-body);
    background:
        radial-gradient(1200px 600px at 80% -10%, rgba(34, 211, 238, 0.06), transparent 60%),
        radial-gradient(900px 500px at 0% 0%, rgba(59, 130, 246, 0.06), transparent 55%),
        var(--bg);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

/* Tech-styled scrollbar */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 6px; border: 2px solid var(--bg); }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* Accessible focus ring for keyboard users */
:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

.screen {
    min-height: 100vh;
}

/* ============ Login Screen ============ */
#loginScreen {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

#loginScreen[hidden] {
    display: none;
}

.login-card {
    background: var(--bg-card);
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 400px;
    border: 1px solid var(--border);
}

.login-header {
    text-align: center;
    margin-bottom: 32px;
}

.login-header .logo {
    font-size: 48px;
    margin-bottom: 12px;
    filter: drop-shadow(0 0 12px var(--accent-glow));
}

.login-header h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 8px;
    font-family: var(--font-display);
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--text-muted);
    font-size: 14px;
}

.login-form .form-group {
    margin-bottom: 20px;
}

.login-form label {
    display: block;
    margin-bottom: 6px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
}

.login-form input {
    width: 100%;
    padding: 12px 14px;
    background: var(--bg);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius);
    color: var(--text);
    font-size: 15px;
    font-family: var(--font-body);
    transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.login-form input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.error-message {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: var(--danger);
    padding: 10px 12px;
    border-radius: var(--radius);
    margin-bottom: 16px;
    font-size: 13px;
}

/* ============ Buttons ============ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 16px;
    border: none;
    border-radius: var(--radius);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: transform 0.15s var(--ease), background 0.15s var(--ease),
                box-shadow 0.15s var(--ease), border-color 0.15s var(--ease);
    text-decoration: none;
    font-family: var(--font-body);
}

.btn:active {
    transform: translateY(0) scale(0.97);
}

.btn-primary {
    background: var(--primary);
    color: white;
}
.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 6px 18px var(--primary-glow);
}

.btn-secondary {
    background: var(--bg-elevated);
    color: var(--text);
    border: 1px solid var(--border-strong);
}
.btn-secondary:hover {
    background: var(--border-strong);
    border-color: var(--accent);
    transform: translateY(-1px);
}

.btn-danger {
    background: transparent;
    color: var(--danger);
    border: 1px solid var(--danger);
}
.btn-danger:hover {
    background: var(--danger);
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 6px 18px rgba(239, 68, 68, 0.35);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 13px;
}

.btn-block {
    width: 100%;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* ============ App Header ============ */
.app-header {
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    padding: 16px 0;
    margin-bottom: 32px;
}

.app-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-left, .header-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.header-left h1 {
    font-size: 20px;
    font-weight: 600;
    font-family: var(--font-display);
    letter-spacing: -0.01em;
}

.header-left .logo {
    font-size: 24px;
    filter: drop-shadow(0 0 6px var(--accent-glow));
}

.user-badge {
    background: var(--bg-elevated);
    padding: 6px 12px;
    border-radius: 999px;
    font-size: 13px;
    color: var(--text-muted);
    font-family: var(--font-mono);
    border: 1px solid var(--border);
}

.user-info {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 2px;
}