:root {
    --bg-color: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --success: #10b981;
    --success-hover: #059669;
    --danger: #ef4444;
    --border: rgba(255, 255, 255, 0.1);
}

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

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-color);
    background-image: radial-gradient(circle at top right, #1e1b4b, #0f172a);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

nav {
    width: 100%;
    padding: 1rem 2rem;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav.hidden { display: none; }

.nav-brand {
    font-size: 1.25rem;
    font-weight: 600;
    background: linear-gradient(to right, #60a5fa, #c084fc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    margin-left: 1.5rem;
    font-size: 0.9rem;
    transition: color 0.2s;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--text-main);
}

.nav-links a.hidden { display: none; }

.app-container {
    width: 100%;
    max-width: 600px;
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    text-align: center;
    margin-top: 4rem;
}

.app-container.hidden { display: none; }

header h1 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

header p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 2rem;
}

input[type="text"], input[type="password"], input[type="email"], select {
    width: 100%;
    padding: 1rem;
    background: rgba(0,0,0,0.2);
    border: 1px solid var(--border);
    color: var(--text-main);
    border-radius: 8px;
    outline: none;
    font-family: inherit;
    margin-bottom: 1rem;
}

.pwd-wrapper {
    position: relative;
    width: 100%;
    margin-bottom: 1rem;
}
.pwd-wrapper input {
    margin-bottom: 0;
    padding-right: 3rem;
}
.pwd-toggle {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    cursor: pointer;
    user-select: none;
    color: var(--text-muted);
}

input:focus, select:focus {
    border-color: var(--primary);
}

button {
    width: 100%;
    padding: 1rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    font-family: inherit;
}

button:hover { transform: translateY(-2px); }

.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-hover); }

.btn-success {
    display: inline-block;
    width: 100%;
    padding: 1rem;
    background: var(--success);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    margin-bottom: 1rem;
}
.btn-success:hover { background: var(--success-hover); transform: translateY(-2px); }

.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text-main); }
.btn-outline:hover { background: rgba(255, 255, 255, 0.05); }

.error-msg {
    color: var(--danger);
    margin-top: 1rem;
    font-size: 0.9rem;
}

.error-msg.hidden { display: none; }

.upload-zone {
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 3rem 2rem;
    cursor: pointer;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.02);
}

.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(59, 130, 246, 0.05);
}

.upload-zone .icon { font-size: 3rem; margin-bottom: 1rem; }
.upload-zone h3 { font-size: 1.2rem; margin-bottom: 0.5rem; }
.upload-zone p { color: var(--text-muted); }

.spinner {
    border: 3px solid rgba(255,255,255,0.1);
    border-top: 3px solid var(--primary);
    border-radius: 50%;
    width: 30px;
    height: 30px;
    animation: spin 1s linear infinite;
    margin: 2rem auto 1rem;
}
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

.success-icon { font-size: 4rem; margin-bottom: 1rem; }
.step.hidden { display: none; }

/* Admin */
.admin-section {
    background: rgba(0,0,0,0.2);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    margin-bottom: 2rem;
    text-align: left;
}
.admin-section h3 { margin-bottom: 1rem; color: var(--text-main); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr 1fr auto; gap: 1rem; align-items: center; }
.form-grid input, .form-grid select { margin-bottom: 0; }
.form-grid button { width: auto; padding: 1rem 2rem; }

.users-table { width: 100%; border-collapse: collapse; }
.users-table th, .users-table td { padding: 1rem; border-bottom: 1px solid var(--border); text-align: left; }
.users-table th { color: var(--text-muted); font-weight: 600; }