/* ===== Global Reset & Variables ===== */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --success: #16a34a;
    --danger: #dc2626;
    --warning: #d97706;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --sidebar-width: 220px;
    --toolbar-height: 56px;
    --radius: 8px;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
    --font: 'Microsoft YaHei', 'PingFang SC', sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; }
body { font-family: var(--font); color: var(--gray-800); background: var(--gray-50); }
a { text-decoration: none; color: inherit; }
input, textarea, select, button { font-family: var(--font); }

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    border-radius: var(--radius);
    border: 1px solid transparent;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
    white-space: nowrap;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { background: #fff; color: var(--gray-700); border-color: var(--gray-300); }
.btn-outline:hover { background: var(--gray-50); border-color: var(--gray-400); }
.btn-danger { background: var(--danger); color: #fff; border-color: var(--danger); }
.btn-danger:hover { background: #b91c1c; }
.btn-success { background: var(--success); color: #fff; }
.btn-sm { padding: 5px 10px; font-size: 13px; }
.btn-lg { padding: 12px 24px; font-size: 16px; }
.full-width { width: 100%; justify-content: center; }
.mt-5 { margin-top: 5px; }

/* ===== Alerts ===== */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius);
    margin-bottom: 16px;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.alert-error, .alert-danger { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-success { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }
.alert-warning { background: #fffbeb; color: #92400e; border: 1px solid #fde68a; }

/* ===== Modal ===== */
.modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    z-index: 9999;
    align-items: center;
    justify-content: center;
}
.modal.active { display: flex; }
.modal-content {
    background: #fff;
    border-radius: var(--radius);
    width: 90%;
    max-width: 520px;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}
.modal-sm { max-width: 400px; }
.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}
.modal-header h3 { font-size: 16px; }
.modal-close {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    color: var(--gray-500);
    line-height: 1;
}
.modal-body { padding: 20px; }
.modal-footer {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    padding: 16px 20px;
    border-top: 1px solid var(--gray-200);
}

/* ===== Toast ===== */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: var(--gray-800);
    color: #fff;
    padding: 10px 20px;
    border-radius: 20px;
    font-size: 14px;
    opacity: 0;
    transition: all 0.3s;
    z-index: 99999;
    white-space: nowrap;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ===== Login Page ===== */
.login-page {
    min-height: 100vh;
    background: linear-gradient(135deg, #1e3a5f 0%, #2563eb 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}
.login-container { width: 100%; padding: 20px; }
.login-box {
    background: #fff;
    border-radius: 16px;
    padding: 40px;
    max-width: 400px;
    margin: 0 auto;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}
.login-header { text-align: center; margin-bottom: 30px; }
.login-header i { font-size: 48px; color: var(--primary); margin-bottom: 12px; display: block; }
.login-header h1 { font-size: 22px; color: var(--gray-800); margin-bottom: 6px; }
.login-header p { color: var(--gray-500); font-size: 14px; }
.form-group { margin-bottom: 18px; }
.form-group label {
    display: block;
    font-size: 14px;
    color: var(--gray-600);
    margin-bottom: 6px;
    font-weight: 500;
}
.form-group input, .form-group textarea, .form-group select {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 14px;
    transition: border-color 0.2s;
    background: #fff;
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}
.btn-login {
    width: 100%;
    padding: 12px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: background 0.2s;
}
.btn-login:hover { background: var(--primary-dark); }
.login-footer { text-align: center; margin-top: 20px; }
.login-footer a { color: var(--primary); font-size: 14px; }

/* ===== Share Modal ===== */
.share-url-box {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}
.share-url-box input {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 13px;
}
.qrcode-box { text-align: center; }
.qrcode-box img { width: 160px; height: 160px; border: 1px solid var(--gray-200); border-radius: var(--radius); }
.qrcode-box p { font-size: 13px; color: var(--gray-500); margin: 8px 0; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .login-box { padding: 30px 20px; }
    .modal-content { width: 95%; }
}